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Timing of food intake: Sounding the alarm about metabolic impairments? A systematic review
Abstract
Growing evidence points to an association between timing of food intake and obesity in humans, raising the question if when to eat matters as much as what and how much to eat. Based on the new definition of obesity as a chronobiological disease, an unusual or late meal timing represent a circadian chronodisruption, leading to metabolic impairments.
Preliminary data from cross-sectional and experimental studies suggest that changes in meal timing can influence obesity and success of weight loss therapy, independently from total energy intake, dietary composition and estimated energy expenditure.
A systematic review of observational and experimental studies in humans was conducted to explore the link between time of food ingestion, obesity and metabolic alterations. Results confirm that eating time is relevant for obesity and metabolism: observational and experimental studies found an association between meal timing, weight gain, hyperglycemia and diabetes mellitus with benefits deriving from an early intake of food in the day in a wide range of individuals. Herein clinical, future perspectives of chronoprevention and chronotherapy of obesity and type 2 diabetes are also provided.
In conclusion, meal timing appears as a new potential target in weight control strategies, and therapeutic strategies should consider this contributor in the prevention of obesity.
... We identified four reviews on meal timing (35)(36)(37)(38) with AMSTAR 2 low (35,36) and critically low (35,36). Overall, the evidence is limited (Table 5). ...
... We identified four reviews on meal timing (35)(36)(37)(38) with AMSTAR 2 low (35,36) and critically low (35,36). Overall, the evidence is limited (Table 5). ...
... We identified four reviews on meal timing (35)(36)(37)(38) with AMSTAR 2 low (35,36) and critically low (35,36). Overall, the evidence is limited (Table 5). ...
Introduction: ‘Meal patterns’ refers to eating frequency, snacking, regularity, and timing. Here also including intermittent fasting. The effect of meal patterns on health is inconsistent and when updating the Nordic Nutrition Recommendations 2023 (NNR2023), summarizing the evidence is important. Aims: To describe the evidence for the role of meal patterns on bodyweight, body composition, and cardiovascular risk factors (i.e. blood pressure and lipid- and glukose metabolism) in healthy people living with normal weight, overweight, or obesity in all age groups. Methods: An initial search in PubMed found 481 reviews, of which 104 were identified based on titles. Of these, 47 were excluded based on title and abstracts. Of the remaining 57 reviews, 16 were included reporting search terms and inclusion/exclusion criteria. In addition, 8 reviews from reference list or known by authors were included. In total, 24 reviews were relevant. Cochrane Library was searched with no results. Results: All reviews were rated low or critically low (AMSTAR 2). No consistent findings on eating frequency and body weight or composition were found in children/adolescents or adults. In snacking, mixed results were found, although among adults, some consistent results showed positive associations between snacking and body weight. In regularity, breakfast skipping showed mixed results in children/adolescents on body weight and composition. Among adults, randomized controlled trials on breakfast skipping showed a minor impact on improved weight loss. In prospective studies on timing, lower energy intake during late afternoon/evening was related to less body weight. Intermittent fasting reduced body weight but was not superior to continuous energy restrictions. Cardiovascular risk factors were assessed in a minority of the reviews, and despite some beneficial effects, the evidence was limited. Conclusion: Given the overall low to critically low quality of the reviews, the evidence is limited and inconclusive. No consistent results providing evidence for setting recommendations for meal patterns were shown. In this regard, meal patterns may vary within the context of an energy balanced and nutritionally adequate diet.
... A high-quality systematic review of 10 studies investigated the link between food intake timing, obesity, and metabolism (n total ¼ 6401) [61]. Included study durations varied from 2 to 12 weeks (interventional) and 20 weekse6 years (observational). ...
... Benefits were evident across healthy, overweight, and metabolically compromised populations. From limited mechanistic evidence, authors hypothesised that later eating may perturb core clock genes and uncouple central/peripheral oscillators [61]. ...
... The recent characterisation of obesity as a chronobiological disease [44,61], and the emergence of intermittent fasting [50] and chrono-nutrition [86] as novel strategies for obesity management, have occurred alongside a shift in the discussion of obesity. Personalised and 'precision medicine' approaches are now advocated for obesity [87,88], with the suggestion that individual genetic and epigenetic factors may help to explain the highly heterogenous responses observed to weight-loss interventions [87]. ...
... chrononutrition as a potential target in both weight loss and metabolic disease interventions. 8,10 Thus far, there are no recommendations on how energy intake should be distributed throughout the day. ...
... However, there is increasing evidence that distributing total energy intake towards the morning and early afternoon, as compared with late afternoon and evening, is favored for weight loss and metabolic improvements. 8,11,12 It has been suggested that later eating patterns, where total energy intake is distributed towards evenings, may cause the desynchronization of peripheral and central circadian rhythms. 13,14 Our central circadian rhythm is responsible for sleep, body temperature, and melatonin production and is controlled by the suprachiasmatic nuclei with light as the major synchronizer. ...
... 13,43 It has also been shown that earlier intakes result in higher thermogenesis and lower glycemic responses. 8,27 Taken together, these findings suggest that the human body has metabolically evolved around earlier-weighted daily energy intake, where darkness in the evening is associated with sleep onset rather than heavy intake of food. 12 42 However, in the current review, some studies also altered macronutrient composition of meals in addition to distribution of total energy intake. ...
Consuming a greater proportion of total energy intake earlier in the day rather than in the evening is proposed to positively influence weight loss and health, potentially due to greater synchronization of human body circadian rhythms. This systematic review provides an update on existing evidence regarding earlier distributed eating patterns in weight loss interventions. Using a robust search strategy in five electronic databases, nine randomized controlled trials investigating the impact of energy intake distribution on weight loss were identified. Following critical appraisal, a random‐effects meta‐analyses found that, in the context of an energy‐reduced diet, distributing energy intake with a focus on earlier intake resulted in significantly greater weight loss (−1.23 kg; 95% CI 2.40, −0.06, p = 0.04). Improvements in HOMA‐IR, fasting glucose, and LDL cholesterol were also seen. The current study provides a timely update on the evidence linking distribution of total daily energy intake and health, showing that a focus on earlier intakes can result in greater short‐term weight loss compared with later intakes. Future studies are needed to elucidate the impact that earlier intakes may have on weight management and metabolic health.
... both associations were partially mediated through (increased) BMI [20]. In concert, a systematic review of the evidence regarding meal timing and obesity (10 studies; n ¼ 6401) concluded that earlier eating was associated with more favourable weight and metabolic outcomes [21]. ...
... Results have clinical relevance. Given the recent characterisation of obesity as a chronobiological disease [21,29], practitioner interest in TRF is increasing. Intermittent fasting [66] and chrononutrition [67] are highlighted as emerging strategies for obesity management. ...
... Intermittent fasting [66] and chrononutrition [67] are highlighted as emerging strategies for obesity management. Observational studies on shift workers [19] and limited cohorts [20,21] are consistent with potential metabolic benefits of earlier, circadian-aligned eating. ...
Background and Aims
The circadian rhythm synchronises metabolic functions between and within tissues, optimising physiology to integrate with environmental and behavioural cycles. Misalignment of nutritional input with the centrally generated rhythm may dysregulate circadian metabolism. Late and extended eating patterns have been identified as risk factors for obesity.
This review seeks to provide a mechanistic overview of nutritional circadian entrainment and its perturbation by misaligned nutritional inputs, with relevance to obesity-associated dysmetabolism.
Methods
A systematic search strategy was conducted within PubMed between March and December 2020. Included studies were formally evaluated for quality. Extracted evidence was coded into key themes.
Results
142 records were screened and 50 accepted. The evidence analysed was moderate-to high-quality and enabled the detailed characterisation of cellular pathways involved in nutritional circadian entrainment.
Results
indicated that diverse nutritional input pathways converge upon key nutrient/redox sensors and nutritionally labile core clock genes, which integrate with circadian metabolic effector pathways, allowing bidirectional communication between circadian clock function and metabolism.
Versus alignment, nutritional misalignment was causally associated with dampening and alteration of core clock rhythms, between-tissue rhythmic decoupling, dysmetabolism, and obesity. Signalling through key circadian nodes, such as NAD+/SIRT, appeared significant in these changes. Misaligned nutritional inputs were associated with altered core circadian temporal dynamics of metabolism and autophagy, and different time division between insulin-sensitive and insulin-resistant metabolic states. Aligned time-restricted feeding relatively strengthened circadian oscillations and protected against diet-induced obesity.
Conclusions
This review suggests value in further investigating circadian-normalising interventions for obesity, such as circadian-aligned time-restricted feeding.
sensitive and insulin-resistant metabolic states. Aligned time-restricted feeding protocols relatively strengthened circadian oscillatory patterns and protected against diet-induced obesity.
... A) Objective markers I) Delayed dim light melatonin onset or reduced melatonin signal in the early evening (Crasson et al., 2004;Fountoulakis et al., 2001;Robillard et al., 2013b;Slyepchenko et al., 2019;Souetre et al., 1989) II) Weight gain (Beccuti et al., 2017;Hutchison & Heilbronn, 2016) III) Metabolic abnormalities (e.g., impaired glucose response, insulin resistance) (Beccuti et al., 2017;Eckel et al., 2015;Geoffroy et al., 2017;Godin et al., 2017;Hutchison & Heilbronn, 2016;Soreca et al., 2012) IV) Abnormal immune and or inflammatory markers (Chu et al., 2019;D'Mello & Swain, 2017;Hickie et al., 2018;Wang et al., 2019a,b) V) Family history of atypical depressive features or bipolar spectrum disorders (Blanco et al., 2012;Melo et al., 2016Melo et al., , 2017Scott et al., 2016) Fig. 2. Schematic representation of key inputs, outputs, and neural pathways of the circadian system relevant to circadian depression. RHT = retinohypothalamic tract; SCN = suprachiasmatic nucleus; PVN = paraventricular nucleus; sPVZ = subparaventricular zone; PinG = pineal gland; Mel = melatonin; Temp = temperature; ANS = autonomic nervous system; Periph Horm = peripheral hormones; PitG = pituitary gland; TSH = thyroid stimulating hormone; ACTH = adrenocorticotropic hormone; Thyr G = thyroid gland; Adr G = adrenal gland; TH = thyroid hormone; Ct = cortisol. ...
... A) Objective markers I) Delayed dim light melatonin onset or reduced melatonin signal in the early evening (Crasson et al., 2004;Fountoulakis et al., 2001;Robillard et al., 2013b;Slyepchenko et al., 2019;Souetre et al., 1989) II) Weight gain (Beccuti et al., 2017;Hutchison & Heilbronn, 2016) III) Metabolic abnormalities (e.g., impaired glucose response, insulin resistance) (Beccuti et al., 2017;Eckel et al., 2015;Geoffroy et al., 2017;Godin et al., 2017;Hutchison & Heilbronn, 2016;Soreca et al., 2012) IV) Abnormal immune and or inflammatory markers (Chu et al., 2019;D'Mello & Swain, 2017;Hickie et al., 2018;Wang et al., 2019a,b) V) Family history of atypical depressive features or bipolar spectrum disorders (Blanco et al., 2012;Melo et al., 2016Melo et al., , 2017Scott et al., 2016) Fig. 2. Schematic representation of key inputs, outputs, and neural pathways of the circadian system relevant to circadian depression. RHT = retinohypothalamic tract; SCN = suprachiasmatic nucleus; PVN = paraventricular nucleus; sPVZ = subparaventricular zone; PinG = pineal gland; Mel = melatonin; Temp = temperature; ANS = autonomic nervous system; Periph Horm = peripheral hormones; PitG = pituitary gland; TSH = thyroid stimulating hormone; ACTH = adrenocorticotropic hormone; Thyr G = thyroid gland; Adr G = adrenal gland; TH = thyroid hormone; Ct = cortisol. ...
... Moreover, as central and peripheral clocks interact via hormonal communication, it is possible that food-induced desynchronisation of peripheral clocks may in turn perturb the brain's master clocks, ultimately affecting circadian regulation of sleep-wake cycles and mood (Haraguchi et al., 2018;Hühne et al., 2018). The timing of food intake relative to internal clock time has also been shown to have effects on weight gain and metabolic disturbance, independent of total calorific intake (Beccuti et al., 2017;Hutchison and Heilbronn, 2016). There is also evidence that other factors that influence metabolism, such as the microbiome, are partially under circadian influence (Montagner et al., 2016). ...
Major mood syndromes are among the most common and disabling mental disorders. However, a lack of clear delineation of their underlying pathophysiological mechanisms is a major barrier to prevention and optimised treatments. Dysfunction of the 24 -h circadian system is a candidate mechanism that has genetic, behavioural, and neurobiological links to mood syndromes. Here, we outline evidence for a new clinical phenotype, which we have called 'circadian depression'. We propose that key clinical characteristics of circadian depression include disrupted 24 -h sleep-wake cycles, reduced motor activity, low subjective energy, and weight gain. The illness course includes early age-of-onset, phenomena suggestive of bipolarity (defined by bidirectional associations between objective motor and subjective energy/mood states), poor response to conventional antidepressant medications, and concurrent cardiometabolic and inflammatory disturbances. Identifying this phenotype could be clinically valuable, as circadian-targeted strategies show promise for reducing depressive symptoms and stabilising illness course. Further investigation of underlying circadian disturbances in mood syndromes is needed to evaluate the clinical utility of this phenotype and guide the optimal use of circadian-targeted interventions.
... It includes timing of eating (e.g., circadian desynchronization negatively influencing metabolism), and how and where the diet is consumed (e.g. mindless eating negatively influences satiation) [38,[89][90][91][92]. ...
... iv) Late eating promotes circadian misalignment: evidence shows that novel dietary patterns marked by late eating promote circadian misalignment, which decreases glucose tolerance, resting energy expenditure, and carbohydrate oxidation, while increasing circulating cortisol as compared to early eating. This results in an increased inflammatory response (example of immunological response) and insulin resistance (example of hormonal response) which are underlying conditions for most NCDs [38,[89][90][91][92]. ...
Background/aim
Building on the evidence for multifaceted effects of different nutrients, foods and dietary patterns is a new priority for nutrition science. This review aims to describe the causal pathways and biological mechanisms that elucidate the associations between different nutrition exposures (nutrients, foods and dietary patterns) and health outcomes.
Methods
A scoping review was conducted in two stages: 1) review of nutrition science textbooks; and 2) a review of reviews of empirical literature using a systematic approach to elucidate causal pathways and biological mechanisms for nutrition exposures and health outcomes. Reviews were eligible for inclusion if they reported biological mechanistic pathways between exposures and outcomes of interest among free-living healthy adults and/or children. Causal pathways within and between the exposures and the outcomes were identified and summarised visually.
Results
A total of seven core textbooks and 1,934 reviews of relevant empirical literature were included. The complexity of the causal pathways and the number of biological mechanisms progressively increases as the nutrition exposure changes from nutrients to foods to dietary patterns. The biological mechanisms demonstrate that associations with beneficial or adverse health outcomes are determined by the contrasting chemical composition and physical structure of the different types and forms of nutrition exposures, and that contextual factors (e.g., food processing) can influence these chemical and physical factors for food and dietary pattern exposures.
Conclusion
This review provides models that can guide future research, and has several implications for the generation and interpretation of the nutrition evidence, and its synthesis and translation to inform nutrition guidelines and policies.
... This resulted in the hypothesis that other factors such as meal timing could explain the higher obesity and cardiometabolic disease prevalence among nightshift workers (59). Observational and experimental studies in humans confirm an association between meal timing, weight gain, glucose (in)tolerance, and diabetes (60). For example, later eating times are associated with the development of overweight (61). ...
... All in all, these findings suggest obesity as a chronobiological disease. However, the development of overweight is multifactorial, and regular food intake during the active phase needs to be considered in addition to known factors such as energy intake and/or dietary composition (60). Although we consider food intake as a "chronodisrupter" in the case of desynchronization, a change of paradigm towards a more positive term, such as "timekeeper", offers the therapeutic chance of meal timing interventions, when considering that meal timing synchronized with the cellular activities can lead to an optimized performance of tissues and organs (91). ...
Meal timing emerges as a crucial factor influencing metabolic health that can be explained by the tight interaction between the endogenous circadian clock and metabolic homeostasis. Mistimed food intake, such as delayed or nighttime consumption, leads to desynchronization of the internal circadian clock and is associated with an increased risk for obesity and associated metabolic disturbances such as type 2 diabetes and cardiovascular diseases. Conversely, meal timing aligned with cellular rhythms can optimize the performance of tissues and organs. In this review, we provide an overview of the metabolic effects of meal timing and discuss the underlying mechanisms. Additionally, we explore factors influencing meal timing, including internal determinants such as chronotype and genetics, as well as external influences like social factors, cultural aspects, and work schedules. This review could contribute to defining meal-timing-based recommendations for public health initiatives and developing guidelines for effective lifestyle modifications targeting the prevention and treatment of obesity and associated metabolic diseases. Furthermore, it sheds light on crucial factors that must be considered in the design of future food timing intervention trials.
... Recent research into dietary factors influencing bodyweight have expanded beyond dietary energy restriction into dietary patterns, including diet quality and the distribution of total energy intake across the day [17][18][19]. Evidence shows that daily energy intakes characterised by small morning meals, larger evening meals, and energy-dense snacking into the late evening are associated with the presence of overweight and obesity [20]. ...
... Reasons for this may include the restrictions placed on individuals by common working hours or 'business hours', which leads to increased evening intake as this is when individuals have the most time to prepare and consume food [32]. While it is convenient to capitalise on the greater availability of 'free' (non-work) time in the evening to prepare and consume larger and more elaborate meals, this pattern of eating has been linked with metabolic disease and increased risk of obesity in middle-aged and older adults [18,20]. Research has also shown that encouraging a shift in energy intake to favour the morning can result in greater weight loss in older adults engaging in weight loss interventions when compared to equally energy-restricted diets that do not emphasise earlier distributed energy intake [21,23,24]. ...
Overweight and obesity impact up to 40% of young women in Australia; however, young women are challenging to recruit to research and are rarely the focus of weight loss interventions. This study aimed to examine dietary patterns in young women (18–25 years; BMI > 25 kg/m2). An analysis of participants’ (mean age: 22.6 year; BMI: 32.2 kg/m2) 3-day food records found young women with overweight/obesity consumed a diet characterised by total energy intake of 9174 (2526) kJ/day, with the first meal at 9:12 am (range: 4:30 am–12:40 pm), the last at 10:43 pm (range: 2:40 pm–2:00 am), and an average eating window of 11.5 h. Young women had poor quality diets, which did not meet dietary recommendations for most core food groups, and high intake of refined carbohydrates. They also reported consuming at least one takeaway meal per day and >30% of total energy intake was from discretionary items. The findings showed that young women with overweight or obesity consume most of their energy intake in the afternoons and late into the evenings and have poor-quality diets with high-discretionary intake, each of which have been shown in previous work to be associated with increased weight and risk of metabolic comorbidities. While these findings require further examination in larger groups with both qualitative and longitudinal data collection to verify the impact of these eating patterns on weight maintenance, the eating behaviours identified here may present a suitable target for novel weight loss interventions in young women, who are an understudied population group in need of tailored weight management solutions.
... La población del estudio consumió una media de 1.635 kcal/día (1.571-1.700). El consumo calórico diario por principios inmediatos fue el siguiente: proteínas 20,1% (19,(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21), hidratos de carbono 48,1% (46,6-49,5) y grasas 31,02% (29,58-32,48), de las cuales saturadas fueron un 25,13% (23,(21)(22)(23)(24)(25)(26)(27)06). Las grasas saturadas suponían un 7,8% (7,08-8,52) de las kcal totales diarias. ...
... Por otro lado, nuestro estudio demostró la correlación de la hora de determinadas comidas con los datos antropométricos. En este sentido, existe evidencia de que cambios en la hora de la ingesta pueden influir no solo en el desarrollo de la obesidad sino también en el éxito de los tratamientos destinados a perder peso, independientemente del total de energía ingerido, la composición de la dieta y el gasto energético estimado 22 . Además, parece que los horarios en los que se realizan las comidas tienen una repercusión en el estado metabólico del organismo. ...
Introduction: Childhood obesity is an extremely prevalent pathology and, in order to be ableto address it, it is necessary to understand the factors that influence on its genesis and mainte-nance. We hypothesise that the timing of meals and sleep, the regularity of these throughoutthe week and a sedentary lifestyle influence the degree of obesity.
Material and methods: We included children and adolescents with obesity who attended a firstcheck-up visit at the Childhood Obesity Unit between January 2018 and February 2020. Thedata were obtained from a questionnaire on food (36-hour intake, frequency of consumption,eating times and habits) and sleep.
Results: The degree of obesity was influenced to a greater extent by later meal times andthe distribution of calories throughout the day (less at breakfast, more at dinner) than by thetotal number of calories ingested. In addition, a lower consumption of vegetables was relatedto a higher degree of obesity. The difference between the hours of sleep at weekends and onweekdays correlated positively with a higher degree of obesity. Finally, the anthropometric datacorrelated negatively with the number of hours of physical activity. Almost half of the childrendid not exercise after school.
Conclusion: In the approach to childhood obesity, it is necessary to include recommendationson the regularity of meal and sleep times, as well as the distribution of calories throughout theday. Additionally, it is necessary to encourage the practice of physical exercise.
... compared to those who did not eat late at night 95 . A recent systematic review and meta-analysis of 10 observational and experimental studies that evaluated the impact of mealtime on obesity and metabolic changes in humans demonstrated a negative influence of late mealtime on weight and metabolism 96 . Furthermore, both observational and experimental studies demonstrated a link between late meal timing with hyperglycemia and diabetes mellitus 96 . ...
... A recent systematic review and meta-analysis of 10 observational and experimental studies that evaluated the impact of mealtime on obesity and metabolic changes in humans demonstrated a negative influence of late mealtime on weight and metabolism 96 . Furthermore, both observational and experimental studies demonstrated a link between late meal timing with hyperglycemia and diabetes mellitus 96 . ...
Sleep is an essential physiological process that profoundly affects a wide range of biological activities. It is now known that sleep supports myriad vital functions in the central nervous system. This includes neural plasticity, learning, memory, cognition, and emotional regulation. Additionally, it affects basic processes such as cardiovascular, immunological, and metabolic activity. Evidence from multiple lines of research has thus shown that good quality of sleep is essential for both survival and optimal functioning of life. Considerable evidence also supports the conclusion that even minimal dysfunctions in circadian regulation can significantly disrupt sleep and broadly affect body physiology. As a consequence, it is now appreciated that the therapy of sleep disorders is more complex than was once thought. At present, several clinical disciplines have recognized the significance of the biological clock in health and illness and are incorporating this knowledge into treatment programs. Recent decades have seen the emergence of chronotherapies, i.e., treatment strategies that are aimed at producing adjustments in the circadian clock. The final objective of these approaches is to affect basic cellular and physiological processes, which in turn may be at the root of disorders in, e.g., immune functioning, metabolic activity, and psychiatric disturbance. It is suggested that the integration of chronobiological perspectives into mainstream medical disciplines would be of significant benefit, both for the reduction of the prevalence of diseases and their treatment. This review considers the physiology of sleep and the importance of timekeeping mechanisms in the regulation of the overall health of individuals.
... compared to those who did not eat late at night (23). A recent systematic review and meta-analysis of 10 observational and experimental studies that assessed the effect of meal timing on obesity and metabolic alterations in humans reported negative impact of late meal timing on weight and metabolism (24). Additionally, both observational and experimental studies reported an association of late mealtime with hyperglycemia and diabetes mellitus (24). ...
... A recent systematic review and meta-analysis of 10 observational and experimental studies that assessed the effect of meal timing on obesity and metabolic alterations in humans reported negative impact of late meal timing on weight and metabolism (24). Additionally, both observational and experimental studies reported an association of late mealtime with hyperglycemia and diabetes mellitus (24). ...
In this article, we reviewed recent data that examined the relationship of circadian rhythm, mealtime, and intermittent fasting with the risk of cardiometabolic dysfunction. We also examined the effect of their interactions on cardiometabolic risks. Furthermore, since major differences exists between Ramadan diurnal intermittent fasting compared to other forms of experimental intermittent fasting, in this article, we further restricted the discussion to Ramadan diurnal intermittent fasting. PubMed and Google Scholar databases were searched using “intermittent fasting,” “time-restricted feeding,” “fasting,” “mealtime,” “circadian rhythm,” and “cardiometabolic risk,” focusing on human studies published after 2013. Recent evidence indicates that meal timing may influence circadian rhythm, as a result, it may also directly or indirectly impact cardiometabolic risk. In humans, several studies suggested that late mealtime is related to an increased risk of poor cardiometabolic health. Nevertheless, large clinical interventional studies are required to assess causality between late mealtime and cardiometabolic morbidity. Currently, evidence indicates that Ramadan diurnal intermittent fasting has several beneficial effects that may reduce the risk of cardiometabolic disorders, such as weight reduction, improvement in lipid profile and glycemic control, reduction in proinflammatory markers, and oxidative stress. Nevertheless, several changes in daily lifestyle routine, happening during the Ramadan month, may affect the all measured markers of cardiometabolic diseases. Summarily, no definitive conclusion about the impact of Ramadan intermittent fasting on oxidative stress can be formulated. Therefore, large, well-designed studies, which control for various confounding factors are required to assess the influence of Ramadan diurnal intermittent fasting on markers of cardiometabolic risk and disorders.
... However, traditional risk factors cannot fully explain the rapid rise of obesity during the past decades. Over the past 10 years, many causes of obesity and metabolic diseases have been identified, such as the timing of food intake (5)(6)(7) . ...
Timing of food intake is an emerging aspect of nutrition; however, there is a lack of research accurately assessing food timing in the context of the circadian system. The study aimed to investigate the relation between food timing relative to clock time and endogenous circadian timing with adiposity and further explore sex differences in these associations among 151 young adults aged 18–25 years. Participants wore wrist actigraphy and documented sleep and food schedules in real time for 7 consecutive days. Circadian timing was determined by dim-light melatonin onset (DLMO). The duration between last eating occasion and DLMO (last EO-DLMO) was used to calculate the circadian timing of food intake. Adiposity was assessed using bioelectrical impedance analysis. Of the 151 participants, 133 were included in the statistical analysis finally. The results demonstrated that associations of adiposity with food timing relative to circadian timing rather than clock time among young adults living in real-world settings. Sex-stratified analyses revealed that associations between last EO-DLMO and adiposity were significant in females but not males. For females, each hour increase in last EO-DLMO was associated with higher BMI by 0·51 kg/m2 (P = 0·01), higher percent body fat by 1·05 % (P = 0·007), higher fat mass by 0·99 kg (P = 0·01) and higher visceral fat area by 4·75 cm2 (P = 0·02), whereas non-significant associations were present among males. The findings highlight the importance of considering the timing of food intake relative to endogenous circadian timing instead of only as clock time.
... The timing of food intake has been studied extensively in the past decade and, in general, later rather than earlier intake of the main meal of the day is associated with worse insulin sensitivity and decreased postprandial thermogenesis [28]. In type 1 diabetes, the extent to which individual meal quantity, timing and composition affects glycaemic control remains largely obscure. ...
Aims/hypothesis
The aim of this work was to investigate the association between macronutrient intakes and continuous glucose monitoring (CGM) metrics in individuals with type 1 diabetes.
Methods
In 470 individuals with type 1 diabetes of the GUTDM1 cohort (65% female, median age 40 [IQR 28–53] years, median diabetes duration 15 [IQR 6–29] years), we used logistic regression to establish associations between macronutrient intakes and the CGM metrics time in range (TIR, time spent between 3.9–10.0 mmol/l blood glucose, optimally set at ≥70%) and time below range (TBR, <3.9 mmol/l blood glucose, optimally set at <4%). ORs were expressed per 1 SD intake of nutrient and were adjusted for other macronutrient intakes, age, sex, socioeconomic status, BMI, duration of type 1 diabetes, pump use, insulin dose and alcohol intake.
Results
The median (IQR) TIR was 67 (51–80)% and TBR was 2 (1–4)%; the mean ± SD energy intake was 6879±2001 kJ, fat intake 75±31 g, carbohydrate intake 162±63 g, fibre intake 20±9 g and protein intake 70±24 g. A higher fibre intake and a lower carbohydrate intake were associated with higher odds of having a TIR≥70% (OR [95% CI] 1.64 [1.22, 2.24] and 0.67 [0.51, 0.87], respectively), whereas solely a higher carbohydrate intake was associated with TBR<4% (OR 1.34 [95% CI 1.02, 1.78]).
Conclusions/interpretation
A higher fibre intake is independently associated with a higher TIR. A higher carbohydrate intake is associated with less time spent in hypoglycaemia, a lower TIR and a higher time above range. These findings warrant confirmatory (interventional) investigations and may impact current nutritional guidelines for type 1 diabetes.
Graphical Abstract
... Systematic and scoping reviews examining the role of chronotype on meal timing and dietary intake have also found a link between late chronotypes and a high consumption of nutritionally poor or high fat foods [3], as well as the tendency to eat main meals later in the day compared to early or intermediate chronotypes [3,62]. This can lead to adverse health outcomes such as weight gain and poorer glycemic control [5]. On the contrary, health-conscious individuals are likely to have greater nutrition knowledge that enable them to override the desire for energy-dense nutrient-poor foods and make more conscious food choices at night [63,64]. ...
Purpose
Young adults eat erratically and later in the day which may impact weight and cardiometabolic health. This cross-sectional study examined relationships between chrononutritional patterns and diet quality in two young adult populations: a university and community sample.
Methods
Three days of dietary data were collected including food images captured using wearable cameras. Chrononutritional variables were extracted: time of first and last eating occasions, caloric midpoint (time at which 50% of daily energy was consumed), number of eating occasions per day, eating window, day-to-day variability of the above metrics, and evening eating (≥20:00h). The Healthy Eating Index for Australian Adults scored diet quality. Statistical analyses controlled for gender, body mass index, and socio-economic status.
Results
No significant associations between chrononutritional patterns and diet quality were found for all participants (n = 95). However, differences in diet quality were found between university (n = 54) and community (n = 41) samples with average diet quality scores of 59.1 (SD 9.7) and 47.3 (SD 14.4), respectively. Of those who extended eating ≥20:00 h, university participants had better diet quality (62.9±SE 2.5 vs. 44.3±SE 2.3, p < 0.001) and discretionary scores (7.9±SE 0.9 vs. 1.6±SE 0.6, p < 0.001) than community participants. University participants consumed predominately healthful dinners and fruit ≥20:00h whereas community participants consumed predominately discretionary foods.
Conclusion
For the general young adult population, meal timing needs to be considered. Food choices made by this cohort may be poorer during evenings when the desire for energy-dense nutrient-poor foods is stronger. However, meal timing may be less relevant for young adults who already engage in healthy dietary patterns.
... In this sense, there is evidence that changes in the time of ingestion can influence not only the development of +Model T. Gavela-Pérez, A. Parra-Rodríguez, C. Vales-Villamarín et al. obesity but also the success of treatments aimed at losing weight, regardless of the total energy ingested, the composition of the diet and the estimated energy expenditure. 22 In addition, it seems that the timing of meals has an impact on the metabolic state of the body. Thus, some articles relate the timing of meals with different patterns of insulin secretion and with changes in hunger and satiety signals. ...
Introduction:
Childhood obesity is an extremely prevalent pathology and, in order to be able to address it, it is necessary to understand the factors that influence on its genesis and maintenance. We hypothesise that the timing of meals and sleep, the regularity of these throughout the week and a sedentary lifestyle influence the degree of obesity.
Material and methods:
We included children and adolescents with obesity who attended a first check-up visit at the Childhood Obesity Unit between January 2018 and February 2020. The data were obtained from a questionnaire on food (36-h intake, frequency of consumption, eating times and habits) and sleep.
Results:
The degree of obesity was influenced to a greater extent by later meal times and the distribution of calories throughout the day (less at breakfast, more at dinner) than by the total number of calories ingested. In addition, a lower consumption of vegetables was related to a higher degree of obesity. The difference between the hours of sleep at weekends and on weekdays correlated positively with a higher degree of obesity. Finally, the anthropometric data correlated negatively with the number of hours of physical activity. Almost half of the children did not exercise after school.
Conclusion:
In the approach to childhood obesity, it is necessary to include recommendations on the regularity of meal and sleep times, as well as the distribution of calories throughout the day. Additionally, it is necessary to encourage the practice of physical exercise.
... In another study, it was demonstrated that individuals who ate lunch late (after 3:00 p.m.) had lower and smaller weight loss during the treatment [467]. A systematic review on the subject showed that the consumption of a higher percentage of calories in late meals can negatively affect body weight and insulin action [468]. ...
Obesity is a chronic disease resulting from multifactorial causes mainly related to lifestyle (sedentary lifestyle, inadequate eating habits) and to other conditions such as genetic, hereditary, psychological, cultural, and ethnic factors. The weight loss process is slow and complex, and involves lifestyle changes with an emphasis on nutritional therapy, physical activity practice, psychological interventions, and pharmacological or surgical treatment. Because the management of obesity is a long-term process, it is essential that the nutritional treatment contributes to the maintenance of the individual’s global health. The main diet-related causes associated with excess weight are the high consumption of ultraprocessed foods, which are high in fats, sugars, and have high energy density; increased portion sizes; and low intake of fruits, vegetables, and grains. In addition, some situations negatively interfere with the weight loss process, such as fad diets that involve the belief in superfoods, the use of teas and phytotherapics, or even the avoidance of certain food groups, as has currently been the case for foods that are sources of carbohydrates. Individuals with obesity are often exposed to fad diets and, on a recurring basis, adhere to proposals with promises of quick solutions, which are not supported by the scientific literature. The adoption of a dietary pattern combining foods such as grains, lean meats, low-fat dairy, fruits, and vegetables, associated with an energy deficit, is the nutritional treatment recommended by the main international guidelines. Moreover, an emphasis on behavioral aspects including motivational interviewing and the encouragement for the individual to develop skills will contribute to achieve and maintain a healthy weight. Therefore, this Position Statement was prepared based on the analysis of the main randomized controlled studies and meta-analyses that tested different nutrition interventions for weight loss. Topics in the frontier of knowledge such as gut microbiota, inflammation, and nutritional genomics, as well as the processes involved in weight regain, were included in this document. This Position Statement was prepared by the Nutrition Department of the Brazilian Association for the Study of Obesity and Metabolic Syndrome (ABESO), with the collaboration of dietitians from research and clinical fields with an emphasis on strategies for weight loss.
... Delayed eating due to prolonged night-time wakefulness leads to a desynchronization between the central and the peripheral circadian clocks. Growing evidence support an association between the timing of food intake and obesity in humans [79]. Late eating is usually accompanied by skipping breakfast, lower adherence to a healthy diet, prolonged eating duration, and higher caloric intake at dinner [68]. ...
Time-restricted feeding (TRF) and Ramadan fasting (RF) have been recently associated with several health outcomes. However, it is not yet clear if they are superior to existing treatments in terms of glucose metabolism, insulin action, and weight loss. This review aims to summarize the current data on the effects of these regimes on body weight, body composition, and glycemia. An electronic search was conducted in PUBMED and SCOPUS databases up to August 2022. Twenty-four records met the inclusion criteria and underwent a risk-of-bias assessment. The main outcomes were: (a) TRF may result in moderate weight loss in individuals with overweight/obesity; when TRF is combined
with caloric restriction, weight loss is >5% of the initial body weight, (b) 14 h of fasting may be as effective as 16 h in terms of weight loss, and (c) TRF may lead to improved insulin sensitivity and glycemic responses/variability throughout the day in individuals with overweight/obesity. Concerning RF, only two studies were available and thus, conclusions were not drawn. TRF may be an effective nutritional approach for weight loss, and the amelioration of glycemic control and insulin sensitivity in individuals with overweight/obesity. However, more long-term, well-designed studies are needed.
... We also found no differences in GM diversity between participants who reported having good sleep quality versus those who were scored as having poorer sleep quality. Previous studies have shown late-night eating to be associated with obesity, [28][29][30] and bacteria of the family Erysipelotrichaceae were reported to be associated with metabolic disorders such as obesity. [31][32] Zhang et al also reported a population shift for Erysipelotrichaceae in post-gastric-bypass obese individuals, indicating the GM alteration due to surgery and differences in food consumption and digestion perturbations. ...
Background:
Disruptions in sleep related to mealtime may contribute to gut microbial imbalances, and put individuals at higher risk for metabolic diseases. The aim of this pilot study was to investigate the relationships between late-night eating habits and sleep quality and duration, with gut microbiota (GM) profiles.
Methods:
In this cross-sectional study, 36 men referred to a clinic were enrolled. In addition to demographic information, each participant completed questionnaires regarding medical history, physical activity, late-night eating habits, sleep quality and sleep duration. The scores from these questionnaires were used to categorize study participants into the following groups: sleep quality (good or poor), late-night eating (yes or no) and sleep duration (<7 or ≥7 hours). Five grams of stool was also obtained from each participant for GM profiling analysis by sequencing.
Results:
The mean age of the study population was 42.1 ± 1.6 years. Firmicutes and Actinobacteria were the two dominant phyla present in all participant samples. Differences in the relative abundance of GM at each taxonomic rank between study groups were insignificant. Only Erysipelotrichales at the order level were found to be significantly different between individuals who had late-night eating habits and those who did not (P & q < 0.05). No other parameter demonstrated a significant difference in GM profiles of participants.
Conclusion:
In this pilot study, we found Erysipelotrichales to be more abundant in individuals with late-night eating habits. Studies with higher sample sizes are warranted to better delineate the possible effects of time of eating on microbial composition.
... [3]). The "timing" of food intake recently emerged as a third key parameter [4][5][6][7]. The temporal aspect of nutrition encompasses both the duration of the daily eating window (number of hours between first and last caloric intake of the day) and the regularity of one's eating habits. ...
In addition to diet quality and quantity, the “timing” of food intake recently emerged as a third key parameter in nutritional and metabolic health. The link between nutrition timing and metabolic homeostasis is in part due to the regulation of daily feeding:fasting cycles and metabolic pathways by the circadian clock. Preclinical feeding regimen studies in rodents are invaluable to further define the modalities of this relationship and get a better understanding of its mechanistic underpinnings. Time-restricted feeding (TRF) and caloric restriction (CR) are examples of feeding regimen at the crossroads of metabolic and circadian regulation. Here we propose methods to implement TRF and CR highlighting the parameters that are relevant to the study of circadian and metabolic health. We also provide methods to determine their impact on the output of the circadian clock by analyzing diurnal expression profiles using 24 h time-series collection as well as their impact on metabolic homeostasis using a glucose tolerance test (GTT).
... At the same time, alendronate can also substantially improve weight gain [31,32]. The improvement in body weight and food intake may better reflect the results of the improvement in bone metabolism and glucose metabolism [33][34][35][36]. ...
Background:
To explore the anti-osteoporosis and anti-diabetes effects and potential underlying mechanisms of treatment with metformin and alendronate in diabetes mellitus mice.
Methods:
Eight-week-old C57 BL/KS db/db and db/+ female mice were evaluated according to the following treatment group for 12 weeks: control group, diabetes mellitus group, diabetes mellitus with metformin group, diabetes mellitus with Alendronate group, diabetes mellitus with metformin plus alendronate group. Glucose level, glucose tolerance test, bone mineral density, bone microarchitecture, bone histomorphometry, serum biomarkers, and qPCR analysis.
Results:
Combined metformin and alendronate can improve progression in glucose metabolism and bone metabolism, including blood glucose levels, blood glucose levels after 4 and 16 hours fasting, glucose tolerance test results, insulin sensitivity and reduces bone loss than the diabetes group. The use of alendronate alone can increase significantly serum glucagon-like peptide-1 levels than the diabetes group. The use of metformin alone can improve bone microstructure such as Tb.Sp and Tb.N of spine in diabetic mice.
Conclusion:
The combined use of alendronate and metformin has an anti-diabetes and anti-osteoporotic effect compared with diabetic mice, but they appear to act no obvious synergistically between alendronate and metformin.
... 119 Thus, the carbohydrate intake at night, a time of decreased insulin sensitivity and lower efficiency of digestion and absorption of carbohydrates, can also be associated with type 2 diabetes. 118,120 Contrary to the results of other reviews, 45,121 we did not find enough evidence to estimate an association between self-reported short sleep duration and risk of cardiovascular disease and systemic arterial hypertension, so it was not significant in this systematic review. This could be explained because the present study was analyzed within the studies raised by the primary outcome (ie, obesity). ...
Context
A possible association between self-reported short sleep duration and risk of obesity has been studied.
Objective
To analyze the association between sleep duration and obesity.
Methods
The LILACS, Medline, Central, Embase, and OpenGrey databases were searched from inception until July 2020. Two authors screened the studies independently according to the PECO strategy, as follows: participants: > 18 years old; exposure: short sleep duration; control: regular sleep; outcome: obesity). Only cohort studies were included. A total of 3286 studies were retrieved with the search strategy, but only 36 were included. Disagreements were resolved by a third author. The quality of studies was assessed with Newcastle-Ottawa Quality Assessment Form for Cohort Studies. The certainty of the evidence was assessed using Grading of Recommendations Assessment, Development, and Evaluation.
Results
Thirty-six studies were included, and 22 contributed quantitative data. Most of the studies (n = 27) assessed sleep by self-report. The meta-analysis showed a significant association between self-reported short sleep and development of obesity, and the chances of developing obesity increased when self-reported sleep duration decreased.
Conclusions
Self-reported short sleep was significantly associated with a higher incidence of obesity, with moderate quality of evidence.
Systematic Review Registration
PROSPERO registration no. CRD42019130143.
... The high prevalence of poor glycemic control (74.8%) is alarming and supporting previous observations [20]. The current results imply that meal timing is a cheap applicable preventive and therapeutic intervention for weight management and improving glycemic target among patients with diabetes mellitus [21]. ...
ntroduction
There is an increasing awareness regarding the effects of chrono-nutrition on glycemic control and weight
regulation. Therefore, this study aimed to determine the relationship between breakfast skipping and late�night eating to body mass index and glycemic control among patients with type 2 diabetes.
Subjects and methods
This cross-sectional study was conducted among 310 patients with diabetes in Tabuk City, Saudi Arabia
during the period from December 2020 to April 2021. A structured questionnaire was used to interview the
participants, the following were reported: demographic data, breakfast skipping, late-night eating, smoking,
level of exercise, family history of diabetes, and diabetes complications. Weight and height were measured to
calculate the body mass index (BMI), and the last glycated hemoglobin was collected to estimate the degree
of glycemic control. Statistical Package for Social Sciences (SPSS Statistics, IBM Corp., Armonk, USA) was
used for data analysis. The ethical committee of the University of Tabuk approved the research.
Results
Out of 310 patients with diabetes (54.8% women), nearly half (45.2%) were breakfast-skippers and 20% eat
late at night. Breakfast skipping was correlated with BMI (Wald, 5.481, 95% CI, 0.154-0.847, P-value, 0.019).
A positive direct correlation was evident between late dinner intake, BMI, and HbA1c (Wald, 4.210, 95% CI,
0.743-0.993, P-value, 0.04 for HbA1c, and Wald, 6.777, 95% CI, 1.0221-1.165, P-value, 0.009 for BMI).
Conclusion
Breakfast skipping and late dinner intake were associated with obesity, while only late dinner consumption
was associated with poor glycemic control. Further larger multi-center studies investigating the chronotype
and glycemic index are recommended.
... Observational studies have found similar conclusions: high energy intake at dinner is related to several obesity indicators [37][38][39]. However, findings are controversial, as suggested by recent systematic reviews and meta-analyses, indicating certain methodological limitations [40][41][42][43]. ...
Background
Previous research has shown that sleep can play a role in obesity and weight loss. However, the association of sleep with weight loss in patients with severe obesity after bariatric surgery remains unexplored. We aimed to evaluate the role of sleep in weight loss evolution in a cohort of patients who underwent sleeve gastrectomy.
Methods
A cohort of 252 patients with severe obesity (75.7% women; age [mean ± SD] 47.7 ± 10.8 years; BMI 44.2 ± 5.9 kg/m²) was followed for 1 year after surgery. Anthropometric, biochemical, physical activity, sleep (bedtime, wakeup time, and sleep duration) and dietary intake variables were collected pre- and post-surgery (1 year). Linear and non-linear regression models were used to examine the associations between sleep variables and weight loss. Participants were grouped into ‘early’ and ‘late’ sleepers according to a bedtime threshold (before or after 24:00 h), and the differences in weight loss, physical activity, meal timing, and dietary intake between groups were studied.
Results
1-h increments in bedtime were linearly associated with less excess weight loss (EWL) [−2.23%; 95%CI: −3.37; −0.70; p = 0.005] 1 year after the sleeve gastrectomy. Late sleepers lost less weight (−5.64% of EWL [95%CI: −10.11; −1.17]; p = 0.014) when compared to early sleepers and showed a higher energy intake after 21:00 h (8.66% of total energy intake [95% CI: 4.87; 12.46]; p < 0.001).
Conclusions
Late bedtime is associated with less success of weight loss 1 year after the sleeve gastrectomy. Late sleepers consumed more of their calories closer to bedtime. Our results highlight the relevance of considering recommendations on bedtime and meal timing for patients after bariatric surgery.
... [90] A recent systematic review and meta-analysis of 10 observational and experimental studies that assessed the effect of meal timing on obesity and metabolic alterations in humans reported a negative impact of late meal timing on weight and metabolism. [91] Eating and staying awake for the whole night and sleeping in the daytime does not equate with getting enough nocturnal sleep. [ [93] A few studies in Saudi Arabia consistently showed a significant and sudden delay in bedtime and rise time during Ramadan. ...
The Saudi Center for Disease Prevention and Control recently prepared a Consensus Statement regarding how much time a person should spend engaged in physical activity, sedentary behavior, and sleep to promote optimal health across all age groups. This paper describes the background literature, methodology, and modified RAND Appropriateness Method and GRADE-ADOLOPMENT approach that guided the development process. A Leadership Group and Consensus Panels were formed, and credible existing guidelines were identified. The Panel identified clear criteria to choose the best practice guidelines for the set objectives after evaluation based on GRADE table evidence, findings table summaries, and draft recommendations. Updating of the selected practice guidelines was performed, and the Consensus Panels separately reviewed the evidence for each behavior and decided to adopt or adapt the selected practice guideline recommendations or create de novo recommendations. Data related to cultural factors that may affect the studied behaviors, such as prayer times, midday napping or “Qailulah”, and the holy month of Ramadan, were also reviewed. Two rounds of voting were conducted to reach a consensus for each behavior.
... Epidemiological studies suggest meal timing or time of energy intake has a relationship with obesity [10,14,26,27], blood pressure [12,28,29], and type 2 diabetes [10,30], but study examining time-of-day patterns of energy intake in relation to insulin resistance is lacking. The "Evening dominant pattern" observed in the present study was associated with higher insulin resistance risk, compared with the "Noon dominant pattern", after adjusting for sociodemographic, lifestyle, and other cardiometabolic risk factors. ...
Evidence shows time-of-day of energy intake are associated with health outcomes; however, studies of time-of-day energy patterns and their health implication are still lacking in the Asian population. This study aims to examine the time-of-day energy intake pattern of Chinese adults and to examine its associations with nutrient intakes, diet quality, and insulin resistance. Dietary data from three 24-h recalls collected during the 2015 China Health and Nutrition Survey (CHNS) were analyzed (n = 8726, aged ≥ 18 years). Time-of-day energy intake patterns were determined by latent class analysis (LCA). General Linear Models and Multilevel Mixed-effects Logistic Regression Models were applied to investigate the associations between latent time-of-day energy intake patterns, energy-adjusted nutrient intakes, diet quality score, and insulin resistance. Three time-of-day energy intake patterns were identified. Participants in the “Evening dominant pattern” were younger, had higher proportions of alcohol drinkers and current smokers. The “Evening dominant pattern” was associated with higher daily energy intake and a higher percentage of energy from fat (%) (p < 0.001), as well as higher insulin resistance risk (OR = 1.21; 95% CI: 1.05, 1.40), after adjusting for multivariate covariates. The highest diet quality score was observed in participants with “Noon dominant pattern” (p < 0.001). A higher proportion of energy in the later of the day was associated with insulin resistance in free-living individuals.
... Temporality, or timing, of eating and the influence on health is a recent area of interest (13)(14)(15)(16)(17). Most of the accumulated evidence has evaluated timing of dietary intake in a classification-based way, e.g., characterizing participants as early energy consumers or later energy consumers based on the timing of the majority of their energy intake throughout the day followed by regression to determine links with health (18)(19)(20)(21). ...
Background:
The integration of time with dietary patterns throughout a day, or temporal dietary patterns (TDPs), have been linked with dietary quality but relations to health are unknown.
Objective:
The association between TDPs and selected health status indicators and obesity, type 2 diabetes (T2D), and metabolic syndrome (MetS) was determined.
Methods:
The first-day 24-h dietary recall from 1627 nonpregnant US adult participants aged 20-65 y from the NHANES 2003-2006 was used to determine timing, amount of energy intake, and sequence of eating occasions (EOs). Modified dynamic time warping (MDTW) and kernel k-means algorithm clustered participants into 4 groups representing distinct TDPs. Multivariate regression models determined associations between TDPs and health status, controlling for potential confounders, and adjusting for the survey design and multiple comparisons (P <0.05/6).
Results:
A cluster representing a TDP with evenly spaced, energy balanced EOs reaching ≤1200 kcal between 06:00 to 10:00, 12:00 to 15:00, and 18:00 to 22:00, had statistically significant and clinically meaningful lower mean BMI (P <0.0001), waist circumference (WC) (P <0.0001), and 75% lower odds of obesity compared with 3 other clusters representing patterns with much higher peaks of energy: 1000-2400 kcal between 15:00 and 18:00 (OR: 5.3; 95% CI: 2.8, 10.1), 800-2400 kcal between 11:00 and 15:00 (OR: 4.4; 95% CI: 2.5, 7.9), and 1000-2600 kcal between 18:00 and 23:00 (OR: 6.7; 95% CI: 3.9, 11.6).
Conclusions:
Individuals with a TDP characterized by evenly spaced, energy balanced EOs had significantly lower mean BMI, WC, and odds of obesity compared with the other patterns with higher energy intake peaks at different times throughout the day, providing evidence that incorporating time with other aspects of a dietary pattern may be important to health status.
... Consuming more calories earlier in the day also could allow for a longer fast overnight, and extending the overnight fast is reported to improve metabolic health [35,36]. In addition, consuming breakfast daily has emerged as a strategy to avoid weight gain [36][37][38]. Results of the present study are consistent with these findings since eating a larger percentage of calories by 16:00 and completing food consumption before 20:00 was associated with better diet quality. ...
Background
The world-wide adoption of Western lifestyles and eating patterns is associated with adverse effects on nutrient intakes. Here we evaluated the relationships between timing of meals and diet quality in Serbia, a Balkan country with a traditional eating pattern that includes the largest meal of the day as a late lunch.
Methods
A dietary survey was done in the Republic of Serbia using a nationally-representative sample of 74 children and 260 non-pregnant adults. Nutrient intakes were calculated from two 24-h recalls. A Dietary Quality Score (DQS) enumerated how many European Union (EU) Science Hub recommendations were met for fruit and vegetables, fiber, saturated fat, sodium, and sugar. We evaluated whether the timing of dietary intakes is associated with DQS and body mass index.
Results
The dietary intakes of children ages 10–17 and adults were similar and were high in total fat intake, with an average of 40% of energy from fat. Mean fruit and vegetable intakes of 473 g/day in adults exceeded the minimal EU recommendation. The most worrisome aspects of the Serbian diet were high intakes of saturated fat, sugar and sodium. Lunch was the meal with the highest mean content of energy, followed by breakfast and dinner, and the average time for lunch was 15:15. Consumption of a higher percentage of calories before 16:00 in adults was associated with higher fruit and vegetable intakes and with higher DQS. The subgroup of adults consuming their largest meal after 20:00 had a lower mean age, more men, and a larger percentage was employed outside of the home. There were no associations of meal timing with BMI, but the prevalence of obesity in this population sample was only 13%.
Conclusions
These results indicate that an earlier meal pattern, and especially consuming the largest meal of the day earlier in the day, was associated with better quality diets. Public health efforts are needed to preserve nutrient intakes as the population shifts away from the traditional Serbian eating pattern. Long-term, deterioration of nutrient intakes could contribute to the increasing rates of obesity that have been observed in Serbia and world-wide.
... O besity is rapidly increasing in prevalence throughout the world. Evidence is accumulating that meal timing can influence the development of obesity and metabolic syndrome (1). In cross-sectional studies, obese individuals reported consuming more meals later in the day compared to randomly selected controls (2). ...
Context
Consuming calories later in the day is associated with obesity and metabolic syndrome. We hypothesized that eating a late dinner alters substrate metabolism during sleep in a manner that promotes obesity.
Objective
To examine the impact of late dinner on nocturnal metabolism in healthy volunteers.
Design and Setting
This is a randomized crossover trial of late dinner (LD, 22:00) versus routine dinner (RD, 18:00), with a fixed sleep period (23:00-07:00) in a laboratory setting.
Participants
20 healthy volunteers (10 males, 10 females), aged 26.0 ± 0.6 years, BMI 23.2 ± 0.7 kg/m2, accustomed to a bedtime between 22:00-01:00.
Interventions
An isocaloric macronutrient diet was administered on both visits. Dinner (35% daily kcal, 50% carbohydrate, 35% fat) with an oral lipid tracer ([2H31] palmitate, 15 mg/kg) was given at 18:00 on RD and 22:00 on LD.
Main Outcome Measures
Nocturnal and next-morning hourly plasma glucose, insulin, triglycerides, free fatty acids (FFAs), cortisol, dietary fatty acid oxidation, and overnight polysomnography.
Results
LD caused a 4-hour shift in the postprandial period, overlapping with the sleep phase. Independent of this shift, the postprandial period following LD was characterized by higher glucose, a triglyceride peak delay, and lower FFA and dietary fatty acid oxidation. LD did not affect sleep architecture, but increased plasma cortisol. These metabolic changes were most pronounced in habitual earlier sleepers determined by actigraphy monitoring.
Conclusion
LD induces nocturnal glucose intolerance, and reduces fatty acid oxidation and mobilization, particularly in earlier sleepers. These effects might promote obesity if they recur chronically.
... 4 The impact of the circadian distribution of food intake on body weight has also been observed in humans. 3,5,6 A recent metaanalysis of four observational studies found a trend (P = .06) for a positive association between evening energy intake and BMI. ...
Individual variability in weight loss in response to a weight loss intervention is commonly observed. Recently, the timing of food intake has been identified as one possible factor implicated in obesity and weight loss. The objective of this study was to further characterize low weight loss responders by assessing the pre‐diet distribution of daily energy and macronutrient intakes. A pooled cohort of men and women (n = 122; aged 39.1 ± 8.2 years; body mass index [BMI] 33.1 ± 3.8 kg/m2) who participated in a 12 to 15 week energy‐restricted intervention (−500 to −700 kcal/d) were included in this study. Participants were categorized into two weight loss groups (ie, low [−1.3 ± 2.3 kg] and high [−6.1 ± 2.1 kg] weight loss). Food intake and distribution of energy and macronutrient intakes were assessed using a 3‐day food record at baseline. The daily distribution of energy intake (% of total energy intake) was similar in the two weight loss groups with the exception of the low weight loss group who consumed a slightly lower proportion of their total energy intake before 9:00 am compared with the high weight loss group (12.5% ± 5.8% vs 15.0% ± 6.6%, respectively, P = .03). In the low weight loss group, the percentage of energy intake consumed after 8:00 pm was positively associated with total energy intake (r = 0.27, P = .04). The results of this study suggest that the timing of food intake measured prior to a weight loss intervention does not permit the characterization of low weight loss responders.
... 6 h) will act to reduce the homeostatic drive for sleep (figure 4), and this will delay sleep onset [161]; exercising close to bedtime will elevate core body temperature and this may delay sleep onset in some people, particularly if the exercise is very vigorous [162]. The delayed sleep may be linked to the fact that sleep initiation seems to involve/require a small reduction in core temperature [163], and exercise may override this circadian driven change in body temperature; feeding during the latter part of the day has been shown to predispose individuals to weight gain and increased susceptibility to metabolic abnormalities such as diabetes II [164]. Weight gain can predispose to obstructive sleep apnoea where the walls of the throat relax and narrow during sleep, interrupting normal breathing [165]. ...
At the core of human thought, for the majority of individuals in the developed nations at least, there is the tacit assumption that as a species we are unfettered by the demands imposed by our biology and that we can do what we want, at whatever time we choose, whereas in reality every aspect of our physiology and behaviour is constrained by a 24 h beat arising from deep within our evolution. Our daily circadian rhythms and sleep/wake cycle allow us to function optimally in a dynamic world, adjusting our biology to the demands imposed by the day/night cycle. The themes developed in this review focus upon the growing realization that we ignore the circadian and sleep systems at our peril, and this paper considers the mechanisms that generate and regulate circadian and sleep systems; what happens mechanistically when these systems collapse as a result of societal pressures and disease; how sleep disruption and stress are linked; why sleep disruption and mental illness invariably occur together; and how individuals and employers can attempt to mitigate some of the problems associated with working against our internal temporal biology. While some of the health costs of sleep disruption can be reduced, in the short-term at least, there will always be significant negative consequences associated with shift work and sleep loss. With this in mind, society needs to address this issue and decide when the consequences of sleep disruption are justified in the workplace.
... Additionally, the timing of meals could impact on body weight regulation [24,25]. Delaying feeding later in the evening might be disadvantageous, due to a desynchrony between central and peripheral circadian clocks [26,27], potentially affecting gut microbiota composition as well as gastrointestinal function and metabolism [28]. ...
... These data are consistent with the idea that OP individuals may be more susceptible to reduced satiety and greater EI during the evening. Evidence has consistently shown an association between EI later in the day and increased BMI (30). ...
Objective:
Appetite responses to 3 days of overfeeding (OF) were examined as correlates of longitudinal weight change in adults classified as obesity prone (OP) or obesity resistant (OR).
Methods:
OP (n = 22) and OR (n = 30) adults consumed a controlled eucaloric and OF diet (140% of energy needs) for 3 days, followed by 3 days of ad libitum feeding. Hunger and satiety were evaluated by visual analog scales. Ghrelin and peptide YY (PYY) levels were measured during a 24-hour inpatient visit on day 3. Body weight and composition were measured annually for 4.0 ± 1.3 years.
Results:
Dietary restraint and disinhibition were greater in OP than OR (mean difference: 3.5 ± 1.2 and 3.3 ± 0.9, respectively; P < 0.01) participants, and disinhibition was associated with longitudinal weight change (n = 48; r = 0.35; P = 0.02). Compared with the eucaloric diet, energy intake fell significantly in OR participants following OF (P = 0.03) but not in OP (P = 0.33) participants. Twenty-four-hour PYY area under the curve values increased with OF in OR (P = 0.02) but not in OP (P = 0.17) participants. Furthermore, changes in PYY levels with OF correlated with measured energy intake (r = -0.36; P = 0.01).
Conclusions:
Baseline disinhibition and PYY responses to OF differed between OP and OR adults. Dietary disinhibition was associated with 5-year longitudinal weight gain. Differences in appetite regulation may underlie differences in propensity for weight gain.
... Information to classify types of diabetes is now widely available to supplement these five traditional classifying factors from various sources: (1) patient surveys of the natural history of the disease (including family history, ethnicity, mental health, medications, and lifestyle) 24 ; (2) anthropomorphic measurements of body characteristics (sometimes based on paper tools based or more efficiently on digital tools); (3) measurements of circulating or urinary molecules or cells, which can include traditional lab tests or biomarkers, including information about continuous glucose concentrations 25 ]; and (4) behavioral measurements of activities such as food intake 26 and exercise that are accessible from sensors. 27 Phenotypic and biomarker information are two traditional dimensions of classifying patients, but the premise of precision medicine is that more valuable characterization is possible by incorporating additional types of assessments that query relevant biological axes comprehensively. ...
Precision medicine refers to the tailoring of medical treatment for an individual based on large amounts of biologic and extrinsic data. The fast advancing fields of molecular biology, gene sequencing, machine learning, and other technologies enable precision medicine to utilize this detailed information to enhance clinical management decision-making for an individual in the real time of the disease course. Traditional clinical decision making is based on reacting to a relatively limited number of phenotypes that are determined by history, physical examination, and conventional lab tests. Precision medicine depends on highly detailed profiling of the patient’s genetic, morphologic, and metabolic makeup. The precision medicine approach can be applied to individuals with diabetes to select treatments most likely to offer benefit and least likely to cause side effects, offering prospects of improved clinical outcomes and economic costs savings over current empiric practices. As genetic, metabolomic, immunologic, and other sophisticated testing becomes less expensive and more widespread in the medical record, it is expected that precision medicine will become increasingly applied to diabetes care.
... Additionally, the timing of meals could impact on body weight regulation [24,25]. Delaying feeding later in the evening might be disadvantageous, due to a desynchrony between central and peripheral circadian clocks [26,27], potentially affecting gut microbiota composition as well as gastrointestinal function and metabolism [28]. ...
Restriction in meal timing has emerged as a promising dietary approach for the management of obesity and dysmetabolic diseases. The present systematic review and meta-analysis summarized the most recent evidence on the effect of time-restricted feeding (TRF) on weight-loss and cardiometabolic variables in comparison with unrestricted-time regimens. Studies involving TRF regimen were systematically searched up to January 2019. Effect size was expressed as weighted mean difference (WMD) and 95% confidence intervals (CI). A total of 11 studies, 5 randomized controlled trials and 6 observational, were included. All selected studies had a control group without time restriction; hours of fasting ranged from 12-h until 20-h and study duration from 4 to 8-weeks. Most studies involved the Ramadan fasting. TRF determined a greater weight-loss than control regimens (11 studies, n = 485 subjects) (WMD: −1.07 kg, 95%CI: −1.74 to −0.40; p = 0.002; I2 = 56.2%), unrelated to study design. The subgroup analysis showed an inverse association between TRF and fat free mass in observational studies (WMD: −1.33 kg, 95%CI: −2.55 to −0.11; p = 0.03; I2 = 0%). An overall significant reduction in fasting glucose concentrations was observed with TRF regimens (7 studies, n = 363 subjects) (WMD: −1.71 mg/dL, 95%CI: −3.20 to −0.21; p = 0.03; I2 = 0%), above all in trials (WMD:-2.45 mg/dL, 95%CI: −4.72 to −0.17; p = 0.03; I2 = 0%). No between-group differences in the other variables were found. TRF regimens achieved a superior effect in promoting weight-loss and reducing fasting glucose compared to approaches with unrestricted time in meal consumption. However, long-term and well-designed trials are needed to draw definitive conclusions.
Increase in the prevalence of obesity has become a major worldwide health problem in adults as well as among children and adolescents. In the last four decades, studies have revealed that the significant increase in the prevalence of obesity has become a pandemic. Obesity is the result of complex interactions between biological, genetic, environmental, and behavioral factors. Indeed, almost all of the children suffering from obesity in early childhood face with being overweight or obese in adolescence. Different phenotypes have different risk factors in the clinical evaluation of obesity. Individuals suffering from metabolically unhealthy obesity (MUO) are at an excess risk of developing cardiovascular diseases (CVDs), several cancer types, and metabolic syndrome (MetS), whereas the metabolically healthy obesity (MHO) phenotype has a high risk of all-cause mortality and cardiometabolic events but not MetS. While most obese individuals have the MUO phenotype, the frequency of the MHO phenotype is at most 10–20%. Over time, approximately three-quarters of obese individuals transform from MHO to MUO. Total adiposity and truncal subcutaneous fat accumulation during adolescence are positively and independently associated with atherosclerosis in adulthood. Obesity, in general, causes a large reduction in life expectancy. However, the mortality rate of morbid obesity is greater among younger than older adults. Insulin resistance (IR) develops with the central accumulation of body fat. MHO patients are insulin-sensitive like healthy normal-weight individuals and have lower visceral fat content and cardiovascular consequences than do the majority of MUO patients. MetS includes clustering of abdominal obesity, dyslipidemia, hyperglycemia, and hypertension. The average incidence of MetS is 3%, with a 1.5-fold increase in the risk of death from all causes in these patients. If lifestyle modifications, dietary habits, and pharmacotherapy do not provide any benefit, then bariatric surgery is recommended to reduce weight and improve comorbid diseases. However, obesity treatment should be continuous in obese patients by monitoring the accompanying diseases and their consequences. In addition to sodium-glucose co-transporter-2 (SGLT2) inhibitors, the long-acting glucagon-like peptide-1 (GLP-1) receptor agonist reduces the mean body weight. However, caloric restriction provides more favorable improvement in body composition than does treatment with the GLP-1 receptor (GLP1R) agonist alone. Combination therapy with orlistat and phentermine are the US Food and Drug Administration (FDA)-approved anti-obesity drugs. Recombinant leptin and synthetic melanocortin-4-receptor agonists are used in rarely occurring, monogenic obesity, which is due to loss of function in the leptin-melanocortin pathway.
Background: This study investigates how lifestyle factors and westernization contribute to obesity and examines the influence of body mass index (BMI) changes and lifestyle factors on "lipitension," a significant risk factor for heart disease and metabolic syndrome. Methods: This prospective study focused on women aged 20-64 without pre-existing hypertension and dyslipidemia who underwent regular medical checkups between April 2016 and March 2022. Anthropometric measurements and blood pressure, along with low-density lipoprotein, high-density lipoprotein, and triglycerides levels, were assessed. Results: Over an average 46.5-month follow-up, 11.5% of initially healthy young and middle-aged women developed lipitension. Categorizing participants based on BMI changes revealed stable (63.8%), decreased (12.5%), and increased (23.8%) groups within this 11.5%. Increased BMI is linked with a heightened hazard risk for lipitension. Women with increased BMI who refrained from snacking (aHR [95% confidence interval (CI)] = 2.750 [1.433-5.279]), avoided late-night eating (aHR [95% CI] = 1.346 [1.032-1.754]), and engaged in alcohol consumption (aHR [95% CI] = 2.037 [1.138-3.646]) showed an elevated risk. Conversely, within the decreased BMI group, behaviors like skipping breakfast (aHR [95% CI] = 0.190 [0.047-0.764]), eating quickly (aHR [95% CI] = 0.457 [0.215-0.972]), and not eating late (aHR [95% CI] = 0.665 [0.467-0.948]) were associated to a reduced lipitension. Subgroup analysis for women with BMI <23 revealed specific behaviors influencing lipitension risk in both BMI-increased and BMI-stable groups. Conclusion: Customized interventions, including for women with BMI <23, enhance heart health, mitigating global lifestyle diseases and obesity.
Keywords: BMI changes; cardiovascular health; lifestyle factors; lipitension; young and middle-aged women.
The purpose of thisdata brief is to characterize food/beverage consumption by U.S. adults duringthe “late evening” time period from 8:00 pm through 11:59 pm. This analysis is based on one day of dietary intake data from What We Eat in America (WWEIA), National Health and Nutrition Examination Survey (NHANES) 2013-2016.
Background
Accurately identifying eating patterns, specifically the timing, frequency, and distribution of eating occasions (EOs), is important for assessing eating behaviors, especially for preventing and managing obesity and type 2 diabetes (T2D). However, existing methods to study EOs rely on self-report, which may be prone to misreporting and bias and has a high user burden. Therefore, objective methods are needed.
Methods
We aim to compare EO timing using objective and subjective methods. Participants self-reported EO with a smartphone app (self-report [SR]), wore the ActiGraph GT9X on their dominant wrist, and wore a continuous glucose monitor (CGM, Abbott Libre Pro) for 10 days. EOs were detected from wrist motion (WM) using a motion-based classifier and from CGM using a simulation-based system. We described EO timing and explored how timing identified with WM and CGM compares with SR.
Results
Participants ( n = 39) were 59 ± 11 years old, mostly female (62%) and White (51%) with a body mass index (BMI) of 34.2 ± 4.7 kg/m ² . All had prediabetes or moderately controlled T2D. The median time-of-day first EO (and interquartile range) for SR, WM, and CGM were 08:24 (07:00-09:59), 9:42 (07:46-12:26), and 06:55 (04:23-10:03), respectively. The median last EO for SR, WM, and CGM were 20:20 (16:50-21:42), 20:12 (18:30-21:41), and 21:43 (20:35-22:16), respectively. The overlap between SR and CGM was 55% to 80% of EO detected with tolerance periods of ±30, 60, and 120 minutes. The overlap between SR and WM was 52% to 65% EO detected with tolerance periods of ±30, 60, and 120 minutes.
Conclusion
The continuous glucose monitor and WM detected overlapping but not identical meals and may provide complementary information to self-reported EO.
Aim:
Biological rhythms are endogenously generated natural cycles that acts as pacemakers of different physiological mechanisms and homeostasis in the organism, and whose disruption increases metabolic risk. The circadian rhythm is reset by light, but it is also regulated by behavioral cues such as timing of food intake. This study investigates whether the chronic consumption of a sweet treat before sleeping can disrupt diurnal rhythmicity and metabolism in healthy rats.
Methods:
For this, thirty-two Fischer rats were administered daily a low dose of sugar (160 mg/Kg, equivalent to 2.5g in humans) as a sweet treat at 8 a.m. or 8 p.m. (ZT0 and ZT12, respectively) for 4 weeks. To elucidate diurnal rhythmicity of clock gene expression and metabolic parameters, animals were sacrificed at different times, including 1, 7, 13 and 19 hours after the last sugar dose (ZT1, ZT7, ZT13 and ZT19).
Results:
Increased body weight gain and higher cardiometabolic risk were observed when sweet treat was administered at the beginning of the resting period. Moreover, central clock and food intake signaling genes varied depending on the snack time. Specifically, the hypothalamic expression of Nampt, Bmal1, Rev-erbα and Cart showed prominent changes in their diurnal expression pattern, highlighting that sweet treat before bedtime disrupts hypothalamic control of energy homeostasis.
Conclusions:
These results show that central clock genes and metabolic effects following a low dose of sugar are strongly time-dependent, causing higher circadian metabolic disruption when it is consumed at the beginning of the resting period, i.e., with the late-night snack.
Prehrambene navike imaju važan utjecaj na zdravlje organizma. Pravilnom prehranom, koja obuhvaća uravnoteženu količinu i kvalitetu unesene hrane, konzumiranje svježeg voća i povrća oslobođenog od raznih štetnih utjecaja (zagađenja, pesticida i sl.), ribe, mesa u odgovarajućim količinama, ograničenje količine šećera, soli i masti i dr. može se unaprijediti zdravstveno stanje organizma te smanjiti rizik oboljenja od pojedinih bolesti. Razvijanje svijesti o pravilnoj prehrani kod adolescenata iznimno je važno u prevenciji oboljenja od različitih kroničnih nezaraznih bolesti u kasnijoj dobi. Istraživanje provedeno na uzorku od 74 maturanta Medicinske škole u Rijeci pokazalo je pozitivan stav maturanata povezan sa zdravom prehranom i prihvaćanjem pravilne prehrane kao načina života. ITM ispitanika iznosio je 23 te ukazuje da u prosjeku imaju normalnu tjelesnu težinu. Rezultati ankete pokazali su zadovoljavajuće prehrambene navike maturanata. Nedostaci u prehrani uočeni su u nedostatnom konzumiranju voća i povrća te ribe. Pažnju je potrebno usmjeriti i na promjene prehrambenih navika tijekom boravka u školi, preskakanje obroka i kasne večere te na dodatnu edukaciju srednjoškolaca o štetnosti alkoholnih pića i duhanskih proizvoda. Daljnjom edukacijom i obrazovnim programima o pravilnoj prehrani i njezinim učincima na zdravlje preventivno se djeluje na zdravlje populacije u cjelini.
Background & Objective: Nowadays, Non-alcoholic fatty liver disease (NAFLD) is becoming the most common liver disease worldwide. In a recent study from the United States (US), the increase in liver mortality was associated with an increased prevalence of non-alcoholic fatty liver disease. It is considered as a Santarpanajanya Vadhias per Ayurvedicliterature. Dietary factors are one of the primary causes for the manifestation of NAFLD. Food timing also matters in the course of disease development. Ayurvedicliterature strictly laid down on certain principles and one among them is the Aaharavidhi Vidhanam. It clearly explains the need for taking the food in right time and in the right amount. This study aims to establish the relationship between the timing of food and NAFLD. Methodology:A cross-sectional study was conducted among the 30 participantsvisiting the KayachikitsaOPD of Vaidyaratnam Ayurveda College, Ollur diagnosed with NAFLD and enquired about their timing of food. Results & Discussion:Among the 30 participants, 76.7% had irregular food habits in which 68.8% belong to female and 85.7% to male. The odds of irregular food habits in females are more than those in males who are diagnosed with NAFLD, but the p value 0.399 indicates there is no significant gender wise priority while analysing the relation between time of food and NAFLD.Conclusion:This study establishes a positive relationship of time of food intake and NAFLD ie, those who are taking food at an irregular time is tend to develop NAFLD
Background: This study examined the association between sedentary behavior, sleep duration, breakfast skipping, and abdominal obesity among postmenopausal women in South Korea. Materials and Methods: A total of 7,270 postmenopausal women were included in this cross-sectional, secondary analysis study, using a nationally representative dataset from the Korea National Health and Nutrition Examination Survey. Results: Sleep duration of fewer than 5 hours/day was associated with an increased risk of abdominal obesity (odds ratio [OR] = 1.29; 95% confidence interval [CI], [1.02-1.63]), compared to sleep duration of 6-8 hours/day after controlling for covariates. Additionally, breakfast skipping was associated with an increased risk of abdominal obesity (OR = 1.45; 95% CI [1.02-2.06]), compared to breakfast eating after covariate adjustment. There was no significant association between sedentary behavior and abdominal obesity. Conclusions: The findings of this study demonstrate that special consideration should be given to behavior modification strategies to improve sleep duration and decrease breakfast skipping to decrease the risk of abdominal obesity in postmenopausal women.
Circadian clocks can be found in nearly all eukaryotic organisms, as well as certain bacterial strains, including commensal microbiota. Exploring intercellular coupling among cell-autonomous circadian oscillators is crucial for understanding how cellular ensembles generate and sustain coherent circadian rhythms on the tissue level, and thus, rhythmic organ functions. Here we describe a protocol for studying intercellular coupling among peripheral circadian oscillators using three-dimensional spheroid cultures in order to measure coupling strength within peripheral clock networks. We use cell spheroids to simulate in vivo tissue integrity, as well as to increase complexity of cell–cell interactions and the abundance of potential coupling factors. Circadian rhythms are monitored using live-cell imaging of spheroids equipped with circadian reporters over several days.
The microbial community colonizing the gastrointestinal tract, collectively termed the gut microbiota, is an important element of the host organism due to its impact on multiple aspects of health. The digestion of food, secretion of immunostimulatory molecules, performance of chemical reactions in the intestine, and production of metabolites by the microbiota contribute to host homeostasis and disease. Recent discoveries indicate that these major functions are not constantly performed over the course of a day, but rather undergo diurnal fluctuations due to compositional and biogeographical oscillations in the microbiota. Here, we summarize the characteristics and origins of diurnal microbiome rhythms as well as their functional consequences for the circadian biology of the host. We describe the major known pathways of circadian host-microbiome communication and discuss possible implications of altered diurnal microbiome rhythms for human disease.
Expected final online publication date for the Annual Review of Nutrition, Volume 42 is August 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
Background
Evening eating has been associated with higher energy intake and lower nutrient density. However, these qualities may not characterize all late evening (LE) eating patterns.
Objective
We sought to characterize U.S. adults’ LE eating patterns on a given day and identify differences, if any, in pattern-specific associations with, and impact on, daily energy intake and total diet quality.
Design
LE eating patterns, energy intakes, and HEI scores were identified using Day-1 dietary recall data from the cross-sectional National Health and Nutrition Examination Survey 2013-2016.
Participants/setting
The sample included adults age ≥20 years (n=9,861). “LE reporters” were respondents who consumed foods/beverages between 20:00 h and 23:59 h on the intake day.
Main outcome measures
Energy intake and HEI-2015 scores by LE status/pattern and the impact of LE consumption on these measures.
Statistical analyses
Cluster analysis assigned individuals to LE eating patterns based on the LE energy contribution of food/beverage groups. Regression models estimated energy intake and HEI-2015 scores; estimates were compared between LE reporters and non-reporters. Similarly, LE’s contribution to total energy and the difference in total HEI inclusive versus exclusive of LE consumption were estimated and compared among patterns.
Results
Among U.S adults, 64.4% were LE reporters. Eleven LE patterns were identified; the six most prevalent patterns (representing 89% of LE reporters) were further analyzed. Daily energy intake in all prevalent patterns except the fruit pattern exceeded that of non-reporters by ≥268 kcal (unadjusted; p<0.001), varying by pattern. Conversely, total HEI score did not differ from that of non-reporters (51.0) in any pattern except the fruit pattern, where it was higher (57.4, unadjusted; p<0.001). Generally, LE consumption's impact on energy was high and its impact on HEI scores was low.
Conclusions
Late evening food/beverage consumption is common among U.S. adults, and LE patterns are not monolithic in their associations with, and impact on, total energy intake and dietary quality.
A molecular circadian clock exists not only in the brain, but also in most cells of the body. Research over the past two decades has demonstrated that it directs daily rhythmicity of nearly every aspect of metabolism. It also consolidates sleep-wake behavior each day into an activity/feeding period and a sleep/fasting period. Otherwise, sleep-wake states are mostly controlled by hypothalamic and thalamic regulatory circuits in the brain that direct overall brain state. Recent evidence suggests that hypothalamic control of appetite and metabolism may be concomitant with sleep-wake regulation, and even share the same control centers. Thus, circadian control of metabolic pathways might be overlaid by sleep-wake control of the same pathways, providing a flexible and redundant system to modify metabolism according to both activity and environment.
Timing of eating relative to sleep and endogenous circadian rhythm impacts weight and cardiometabolic health. We used qualitative methods to explore what influences the "when" of eating and sleeping. We conducted 37 one-on-one semi-structured interviews among participants with a body mass index (BMI) ≥ 25 kg/m2 recruited from three internal medicine clinics affiliated with an urban academic hospital. Participants (70.3% Female; 51.4% White; Age range: 21-83 years old) completed measures of social jetlag, physical activity, eating habits, and mobile application use and participated in interviews following a guide developed by the study team. Responses were recorded, transcribed and coded sequentially by two trained researchers using editing-style analysis to identify themes. We identified two main themes, each with subthemes: 1) influences on the "when" of eating and sleeping, with subthemes including social jetlag and being overscheduled, and 2) contextualizing beliefs and perceptions about the "when" of eating and sleeping, with subthemes including perceived recommendations for timing of eating and sleeping, and alignment of behaviors with perceived recommendations. Many participants noted being more flexible in their eating and sleeping times on work-free vs work days. The themes this study identified should be considered when designing interventions that influence the timing of eating and sleeping for weight management.
Article Info ABSTRACT 10.30699/jambs.28.126.41 Background & Objective: Recent studies have shown the effect of meal timing on weight-loss diet success with controversial results. The current study evaluated the effect of evening meal timing on weight and body mass index (BMI) in overweight/obese subjects who were on a standard weight-loss diet. Materials & Methods: A total of 70 obese/overweight employees of Ahvaz Jundishapur University of Medical Sciences took part in this randomized clinical trial (RCT). Participants were randomly assigned into a limited meal timing weight-loss (LMTWL) group with the last meal before 06:00 PM and a non-limited meal timing weight-loss (NLMTWL) group with the last meal before 12:00 AM. All participants followed a standard weight-loss diet as follows: 53% carbohydrate 30% fat and 17% protein. Weight and body mass index was measured at the run-in-period (2 weeks), baseline and the end of four weeks. Independent sample T-test was used to compare parametric continuous variables between the two groups. Results: Of participants, 60% were female. However, there was no significant difference between the two groups based on sex. Also, age, height, physical activity level, BMI and energy intake was similar between the two groups. There were no differences in LMTWL and NLMTWL groups based on weight (P=0.89) and BMI (P=0.91) before and after four weeks of the intervention. Conclusion: Meal timing did not influence the amount of weight lost by overweight/obese subjects on a weight-loss diet. However, more RCTs with larger samples and longer follow-up durations (with a focus on nutrient intake, circadian clock patterns, and the interaction between genotype and chronotype) are needed to confirm this finding.
Experimental research suggests that food timing is associated with weight regulation. However, the association between the distribution of energy intake (EI) throughout the day and weight gain in the population is uncertain. A cohort of 4243 individuals (49·9 % men, 50·1 % women) aged ≥18 years was selected in 2008–2010 and followed-up through 2012. At baseline, food consumption for a typical week in the previous year was collected with a validated dietary history, and EI was assessed at six eating occasions: breakfast, mid-morning meal, lunch, mid-afternoon meal, dinner and snacking (at any other moment). Individuals were classified into sex-specific quartiles of %EI for each eating occasion. The cut-off points for increasing quartiles of %EI at lunch were 34·4, 40·8 and 47·7 % in men and 33·2, 39·4 and 46·1 % in women. Weight was self-reported at baseline and at the end of follow-up. During a 3·5-year follow-up, 16·3 % of study participants gained >3 kg. Compared with those in the lowest quartile of %EI at lunch, the multivariate OR of gaining >3 kg was 0·79 (95 % CI 0·63, 0·99) in the second quartile, 0·82 (95 % CI 0·64, 1·04) in the third quartile and 0·62 (95 % CI 0·47, 0·80) in the highest quartile (
P
trend
: 0·001). The association was stronger among women and those with overweight or obesity. No association was found between the %EI at the rest of the eating occasions and weight gain. In conclusion, a higher %EI at lunch was associated with a lower risk of weight gain; this may help weight control through the appropriate distribution of daily EI.
Background:
Recent research has demonstrated a relationship between the timing of food intake and weight loss in humans. However, whether the meal timing can be associated with weight loss in patients treated with bariatric surgery is unknown.
Objective:
To evaluate the role of food-timing in the evolution of weight loss in a sample of 270 patients that underwent bariatric surgery with a follow-up of 6 years.
Methods:
Participants (79% women; age [mean ± SD]: 52 ± 11 years; BMI: 46.5 ± 6.0 kg/m(2)) were classified according their weight loss response patterns after bariatric surgery: good weight-loss-responders (67.8%), primarily poor weight-loss-responders (10.8%) or secondarily poor weight-loss-responders (21.4%). Then, they were grouped in early-eaters and late-eaters, according to the timing of the main meal (before or after 15:00 h). Obesity and biochemical parameters, energy and macronutrients intake, energy expenditure, sleep duration, and chronotype were studied.
Results:
The percentage of late eaters (after 15:00 h) was significantly higher in the primarily poor weight-loss-responders (∼70%) than in both secondarily poor weight-loss-responders (∼42%) and good weight-loss-responders (∼37%) (p = 0.011). Consistently, primarily poor weight-loss-responders had lunch later as compared to good and secondarily poor weight-loss-responders (p = 0.034). Age, gender and type of surgery were not determining. Surprisingly, obesity-related variables, biochemical parameters, pre-surgical total energy expenditure, sleep duration, chronotype, calorie intake and macronutrients distribution, were similar among groups.
Conclusions:
Weight loss effectiveness after bariatric surgery is related to the timing of the main meal. Our preliminary results suggest that the timing of food intake is important for weight regulation and that eating at the right time may be a relevant factor to consider in weight loss therapy even after bariatric surgery.
Significance
Shift work is a risk factor for hypertension, inflammation, and cardiovascular disease, even after controlling for traditional risk factors. Shift workers frequently undergo circadian misalignment (i.e., misalignment between the endogenous circadian system and 24-h environmental/behavioral cycles). This misalignment has been proposed to explain, in part, why shift work is a risk factor for hypertension, inflammation, and cardiovascular disease. However, the impact of circadian misalignment per se on 24-h blood pressure and inflammatory markers is poorly understood. We show—under highly controlled laboratory conditions—that short-term circadian misalignment increases 24-h blood pressure and inflammatory markers in healthy adults. Our findings may help explain why shift work increases hypertension, inflammation, and cardiovascular disease risk.
Systematic reviews should build on a protocol that describes the rationale, hypothesis, and planned methods of the review; few reviews report whether a protocol exists. Detailed, well-described protocols can facilitate the understanding and appraisal of the review methods, as well as the detection of modifications to methods and selective reporting in completed reviews. We describe the development of a reporting guideline, the Preferred Reporting Items for Systematic reviews and Meta-Analyses for Protocols 2015 (PRISMA-P 2015). PRISMA-P consists of a 17-item checklist intended to facilitate the preparation and reporting of a robust protocol for the systematic review. Funders and those commissioning reviews might consider mandating the use of the checklist to facilitate the submission of relevant protocol information in funding applications. Similarly, peer reviewers and editors can use the guidance to gauge the completeness and transparency of a systematic review protocol submitted for publication in a journal or other medium.
Aims/hypothesis
We investigated whether therapy with the entire daily dose of ≥1 hypertension medications at bedtime exerts greater reduction in the risk of new-onset diabetes than therapy with all medications upon awakening.
Methods
We conducted a prospective, randomised, open-label, blinded endpoint trial of 2,012 hypertensive patients without diabetes, 976 men and 1,036 women, 52.7 ± 13.6 years of age. Patients were randomised, using a computer-generated allocation table, to ingest all their prescribed hypertension medications upon awakening or the entire daily dose of ≥1 of them at bedtime. Investigators blinded to the hypertension treatment scheme of the patients assessed the development of new-onset diabetes.
Results
During a 5.9-year median follow-up, 171 participants developed type 2 diabetes. Patients of the bedtime, compared with the morning-treatment group, showed: (1) significantly lower asleep BP mean, greater sleep-time relative BP decline and attenuated prevalence of non-dipping at the final evaluation (32% vs 52%, p < 0.001); and (2) significantly lower HR of new-onset diabetes after adjustment for the significant influential characteristics of fasting glucose, waist circumference, asleep systolic BP mean, dipping classification and chronic kidney disease (CKD) (unadjusted HR 0.41 [95% CI 0.29, 0.58]; adjusted HR 0.43 [0.31, 0.61]; event-rate 4.8% vs 12.1% with bedtime and morning treatment, respectively; p < 0.001). Greater benefit was observed for bedtime compared with awakening treatment with angiotensin receptor blockers (ARBs) (HR 0.39 [0.22, 0.69]; p < 0.001), ACE inhibitors (0.31 [0.12, 0.79], p = 0.015) and β-blockers (0.35 [0.14, 0.85], p = 0.021).
Conclusions/interpretation
In hypertensive patients without diabetes, ingestion of ≥1 BP-lowering medications at bedtime, mainly those modulating or blocking the effects of angiotensin II, compared with ingestion of all such medications upon awakening, results in improved ambulatory BP (ABP) control (significant further decrease of asleep BP) and reduced risk of new-onset diabetes.
Trial registration: ClinicalTrials.gov NCT00295542
Funding: This independent investigator-promoted research was supported by unrestricted grants from Ministerio de Ciencia e Innovación (SAF2006-6254-FEDER; SAF2009-7028-FEDER); Xunta de Galicia (PGIDIT03-PXIB-32201PR; INCITE07-PXI-322003ES; INCITE08-E1R-322063ES; INCITE09-E2R-322099ES; 09CSA018322PR); and Vicerrectorado de Investigación, University of Vigo.
Background/objectives:
Food-induced thermogenesis is generally reported to be higher in the morning, although contrasting results exist because of differences in experimental settings related to the preceding fasting, exercise, sleeping and dieting. To definitively answer to this issue, we compared the calorimetric and metabolic responses to identical meals consumed at 0800 hours and at 2000 hours by healthy volunteers, after standardized diet, physical activity, duration of fast and resting.
Subjects/methods:
Twenty subjects (age range 20-35 years, body mass index=19-26 kg m(-)(2)) were enrolled to a randomized cross-over trial. They randomly received the same standard meal in the morning and, 7 days after, in the evening, or vice versa. A 30-min basal calorimetry was performed; a further 60-min calorimetry was done 120-min after the beginning of the meal. Blood samples were drawn every 30-min for 180-min. General linear models, adjusted for period and carry-over, were used to evaluate the 'morning effect', that is, the difference of morning delta (after-meal minus fasting values) minus evening delta (after-meal minus fasting values) of the variables.
Results:
Fasting resting metabolic rate (RMR) did not change from morning to evening; after-meal RMR values were significantly higher after the morning meal (1916; 95% confidence interval (CI)=1792, 2041 vs 1756; 1648, 1863 kcal; P<0.001). RMR was significantly increased after the morning meal (90.5; 95% CI=40.4, 140.6 kcal; P<0.001), whereas differences in areas-under-the-curve for glucose (-1800; -2564,-1036 mg dl(-1) × h, P<0.001), log-insulin (-0.19; -0.30,-0.07 μU ml(-1) × h; P=0.001) and fatty free acid concentrations (-16.1;-30.0,-2.09 mmol l(-1) × h; P=0.024) were significantly lower. Delayed and larger increases in glucose and insulin concentrations were found after the evening meals.
Conclusions:
The same meal consumed in the evening determined a lower RMR, and increased glycemic/insulinemic responses, suggesting circadian variations in the energy expenditure and metabolic pattern of healthy individuals. The timing of meals should probably be considered when nutritional recommendations are given.International Journal of Obesity advance online publication, 25 August 2015; doi:10.1038/ijo.2015.138.
Despite large improvements in the management of
glucose levels and in the treatment of cardiovascular
risk factors, the mortality rate in individuals with type
1 diabetes (T1D) is still high. Recently, Lind
et al
found
that T1D individuals with glycated hemoglobin levels
of 6.9% or lower had a risk of death from any cause
or from cardiovascular causes that is twice as high as
the risk for matched controls. T1D is a chronic disease
with an early onset (
e.g.
, pediatric age) and thus in
order to establish a clear correlation between death
rate and the glycometabolic control, the whole history
of glycemic control should be considered; particularly in
the early years of diabetes. The switch from a normo-
to hyperglycemic milieu in an individual with T1D in
the pediatric age, represents a stressful event that may
impact outcomes and death rate many years later. In
this paper we will discuss the aforementioned issues,
and offer our view on these findings, paying a particular
attention to the several alterations occurring in the
earliest phases of T1D and to the many factors that
may be associated with the chronic history of T1D. This
may help us to better understand the recently published
death rate data and to develop future innovative and
effective preventive strategies.
Significance
It is established that glucose tolerance decreases from the morning to the evening, and that shift work is a risk factor for diabetes. However, the relative importance of the endogenous circadian system, the behavioral cycle (including the sleep/wake and fasting/feeding cycles), and circadian misalignment on glucose tolerance is unclear. We show that the magnitude of the effect of the endogenous circadian system on glucose tolerance and on pancreatic β-cell function was much larger than that of the behavioral cycle in causing the decrease in glucose tolerance from morning to evening. Also, independent from circadian phase and the behavioral cycle, circadian misalignment resulting from simulated night work lowered glucose tolerance—without diminishing effects upon repeated exposure—with direct relevance for shift workers.
Background/objectives:
Timing of food intake associates with body weight regulation, insulin sensitivity and glucose tolerance. However, the mechanism is unknown. The aim of this study was to investigate the effects of changes in meal timing on energy-expenditure, glucose-tolerance and circadian-related variables.
Subjects/methods:
Thirty-two women (aged 24±4 years and body mass index 22.9±2.6 kg m(-2)) completed two randomized, crossover protocols: one protocol (P1) including assessment of resting-energy expenditure (indirect-calorimetry) and glucose tolerance (mixed-meal test) (n=10), the other (P2) including circadian-related measurements based on profiles in salivary cortisol and wrist temperature (Twrist) (n=22). In each protocol, participants were provided with standardized meals (breakfast, lunch and dinner) during the two meal intervention weeks and were studied under two lunch-eating conditions: Early Eating (EE; lunch at 13:00) and Late Eating (LE; lunch 16:30).
Results:
LE, as compared with EE, resulted in decreased pre-meal resting-energy expenditure (P=0.048), a lower pre-meal protein-corrected respiratory quotient (CRQ) and a changed post-meal profile of CRQ (P=0.019). These changes reflected a significantly lower pre-meal utilization of carbohydrates in LE versus EE (P=0.006). LE also increased glucose area under curve above baseline by 46%, demonstrating decreased glucose tolerance (P=0.002). Changes in the daily profile of cortisol and Twrist were also found with LE blunting the cortisol profile, with lower morning and afternoon values, and suppressing the postprandial Twrist peak (P<0.05).
Conclusions:
Eating late is associated with decreased resting-energy expenditure, decreased fasting carbohydrate oxidation, decreased glucose tolerance, blunted daily profile in free cortisol concentrations and decreased thermal effect of food on Twrist. These results may be implicated in the differential effects of meal timing on metabolic health.
BACKGROUND:
Short sleep duration and decreased sleep quality are emerging risk factors for obesity and its associated morbidities. Chronotype, an attribute that reflects individual preferences in the timing of sleep and other behaviors, is a continuum from morningness to eveningness. The importance of chronotype in relation to obesity is mostly unknown. Evening types tend to have unhealthy eating habits and suffer from psychological problems more frequently than Morning types, thus we hypothesized that eveningness may affect health parameters in a cohort of obese individuals reporting sleeping less than 6.5 hours per night.
METHODOLOGY AND PRINCIPAL FINDINGS:
BASELINE DATA FROM OBESE (BMI: 38.5±6.4 kg/m(2)) and short sleeping (5.8±0.8 h/night by actigraphy) participants (n = 119) of the Sleep Extension Study were analyzed (www.ClinicalTrials.gov, identifier NCT00261898). Assessments included the Horne and Ostberg Morningness-Eveningness questionnaire, a three-day dietary intake diary, a 14-day sleep diary, 14 days of actigraphy, and measurements of sleep apnea. Twenty-four hour urinary free cortisol, 24 h urinary norepinephrine and epinephrine levels, morning plasma ACTH and serum cortisol, fasting glucose and insulin, and lipid parameters were determined. Eveningness was associated with eating later in the day on both working and non-working days. Progression towards eveningness was associated with an increase in BMI, resting heart rate, food portion size, and a decrease in the number of eating occasions and HDL-cholesterol. Evening types had overtly higher 24 h urinary epinephrine and morning plasma ACTH levels, and higher morning resting heart rate than Morning types. In addition, Evening types more often had sleep apnea, independent of BMI or neck circumference.
CONCLUSIONS:
Eveningness was associated with eating later and a tendency towards fewer and larger meals and lower HDL-cholesterol levels. In addition, Evening types had more sleep apnea and higher stress hormones. Thus, eveningness in obese, chronically sleep-deprived individuals compounds the cardiovascular risk associated with obesity.
OBJECTIVE
To examine whether chronotype and daily caloric distribution are associated with glycemic control in patients with type 2 diabetes independently of sleep disturbances.RESEARCH DESIGN AND METHODS
Patients with type 2 diabetes had a structured interview and completed questionnaires to collect information on diabetes history and habitual sleep duration, quality, and timing. Shift workers were excluded. A recently validated construct derived from mid-sleep time on weekends was used as an indicator of chronotype. One-day food recall was used to compute the temporal distribution of caloric intake. Hierarchical linear regression analyses controlling for demographic and sleep variables were computed to determine whether chronotype was associated with HbA1c values and whether this association was mediated by a higher proportion of caloric intake at dinner.RESULTSWe analyzed 194 completed questionnaires. Multiple regression analyses adjusting for age, sex, race, BMI, insulin use, depressed mood, diabetes complications, and perceived sleep debt found that chronotype was significantly associated with glycemic control (P = 0.001). This association was partially mediated by a greater percentage of total daily calories consumed at dinner.CONCLUSIONS
Later chronotype and larger dinner were associated with poorer glycemic control in patients with type 2 diabetes independently of sleep disturbances. These results suggest that chronotype may be predictive of disease outcomes and lend further support to the role of the circadian system in metabolic regulation.
Background:
There is emerging literature demonstrating a relationship between the timing of feeding and weight regulation in animals. However, whether the timing of food intake influences the success of a weight-loss diet in humans is unknown.
Objective:
To evaluate the role of food timing in weight-loss effectiveness in a sample of 420 individuals who followed a 20-week weight-loss treatment.
Methods:
Participants (49.5% female subjects; age (mean ± s.d.): 42 ± 11 years; BMI: 31.4 ± 5.4 kg m(-2)) were grouped in early eaters and late eaters, according to the timing of the main meal (lunch in this Mediterranean population). 51% of the subjects were early eaters and 49% were late eaters (lunch time before and after 1500 hours, respectively), energy intake and expenditure, appetite hormones, CLOCK genotype, sleep duration and chronotype were studied.
Results:
Late lunch eaters lost less weight and displayed a slower weight-loss rate during the 20 weeks of treatment than early eaters (P=0.002). Surprisingly, energy intake, dietary composition, estimated energy expenditure, appetite hormones and sleep duration was similar between both groups. Nevertheless, late eaters were more evening types, had less energetic breakfasts and skipped breakfast more frequently that early eaters (all; P<0.05). CLOCK rs4580704 single nucleotide polymorphism (SNP) associated with the timing of the main meal (P=0.015) with a higher frequency of minor allele (C) carriers among the late eaters (P=0.041). Neither sleep duration, nor CLOCK SNPs or morning/evening chronotype was independently associated with weight loss (all; P>0.05).
Conclusions:
Eating late may influence the success of weight-loss therapy. Novel therapeutic strategies should incorporate not only the caloric intake and macronutrient distribution - as is classically done - but also the timing of food.
Associations between timing of eating occasions and their nutrient composition and health have been described in interventional and cross-sectional studies. However, data from longitudinal data are limited. This study examined 17-year changes in energy and macronutrient intake across eating occasions in the 1946 British birth cohort.
Data were obtained from the 1946 British birth cohort. Cohort members completed 5d-estimated diaries at ages 36 (1982), 43 (1989) and 53 years (1999). Data from subjects who provided dietary data at all three time points were analysed (n = 1253). Repeated-measures analysis of variance with post hoc Bonferroni's adjustment was used to examine changes in energy and macronutrient at breakfast, mid-morning, lunch, mid-afternoon, evening and extra meal slots between 1982 and 1999. Analyses were stratified by sex and social class.
The proportion of energy and macronutrients consumed at lunch declined between 1982 and 1999, which was compensated by a greater intake in the mid-afternoon and evening. This trend was seen across sex and social class, although women and adults with a non-manual occupation reported greater energy, carbohydrate and non-starch polysaccharide intake at breakfast in 1982 and had a higher protein intake in the evening compared with men and adults with a manual occupation.
The timing of energy and nutrient intake has shifted slightly over time, with a greater proportion of intake later in the day. The association between the observed sex and occupational social class differences in eating profiles and chronic disease warrants investigation.
Shiftworkers have a higher risk of CHD and type 2 diabetes. They consume a large proportion of their daily energy and carbohydrate intake in the late evening or night-time, a factor which could be linked to their increase in disease risk. We compared the metabolic effects of varying both dietary glycaemic index (GI) and the time at which most daily energy intake was consumed. We hypothesised that glucose control would be optimal with a low-GI diet, consumed predominantly early in the day. A total of six healthy lean volunteers consumed isoenergetic meals on four occasions, comprising either high- or low-GI foods, with 60 % energy consumed predominantly early (breakfast) or late (supper). Interstitial glucose was measured continuously for 20 h. Insulin, TAG and non-esterified fatty acids were measured for 2 h following every meal. Highest glucose values were observed when large 5021 kJ (1200 kcal) high-GI suppers were consumed. Glucose levels were also significantly higher in predominantly late high- v. low-GI meals (P < 0·01). Using an estimate of postprandial insulin sensitivity throughout the day, we demonstrate that this follows the same trend, with insulin sensitivity being significantly worse in high energy consumed in the evening meal pattern. Both meal timing and GI affected glucose tolerance and insulin secretion. Avoidance of large, high-GI meals in the evening may be particularly beneficial in improving postprandial glucose profiles and may play a role in reducing the risk of type 2 diabetes; however, longer-term studies are needed to confirm this.
We prospectively investigated in hypertensive patients with type 2 diabetes if bedtime treatment with ≥1 hypertension medications exerts better blood pressure control and cardiovascular risk reduction than conventional therapy, in which all medications are ingested in the morning.
We conducted a prospective, randomized, open-label, blinded end point trial on 448 hypertensive patients with type 2 diabetes, 255 men/193 women, mean ± SD age 62.5 ± 10.8 years, randomized to ingest all their prescribed hypertension medications upon awakening or ≥1 of them at bedtime. Ambulatory blood pressure was measured for 48 h at baseline and again annually or even more frequently (quarterly) after adjustments in treatment.
After a median follow-up of 5.4 years, patients ingesting ≥1 hypertension medications at bedtime showed a significantly lower cardiovascular risk (adjusted by age and sex) than subjects ingesting all medications upon awakening (hazard ratio 0.33 [95% CI 0.21-0.54]; P < 0.001). The difference between groups in the adjusted risk of major events (cardiovascular death, myocardial infarction, and stroke) was also statistically significant (0.25 [0.10-0.61]; P = 0.003). Patients treated at bedtime showed significantly lower sleep time blood pressure mean and higher prevalence of controlled ambulatory blood pressure (62.5 vs. 50.9%; P = 0.013). There was a significant 12% cardiovascular risk reduction per each 5 mmHg decrease in asleep systolic blood pressure during follow-up (P < 0.001).
Among patients with diabetes, treatment with ≥1 hypertension medications at bedtime, compared with all medications upon waking, resulted in improved ambulatory blood pressure control and significantly reduced cardiovascular morbidity and mortality.
Clinical studies have documented morning-evening, administration-time differences of several different classes of hypertension medications in blood pressure (BP)-lowering efficacy, duration of action, safety profile, and/or effects on the circadian BP pattern. In spite of these published findings, most hypertensive subjects, including those under combination therapy, are instructed by their physicians and pharmacists to ingest all of their BP-lowering medications in the morning. The potential differential reduction of cardiovascular (CVD) morbidity and mortality risk by a bedtime versus upon-awakening treatment schedule has never been evaluated prospectively. The prospective MAPEC study was specifically designed to test the hypothesis that bedtime chronotherapy with >= 1 hypertension medications exerts better BP control and CVD risk reduction than conventional therapy, i.e., all medications ingested in the morning. A total of 2156 hypertensive subjects, 1044 men/1112 women, 55.6 +/- 13.6 (mean +/- SD) yrs of age, were randomized to ingest all their prescribed hypertension medications upon awakening or >= 1 of them at bedtime. At baseline, BP was measured at 20-min intervals from 07: 00 to 23: 00 h and at 30-min intervals at night for 48 h. Physical activity was simultaneously monitored every min by wrist actigraphy to accurately determine the beginning and end of daytime activity and nocturnal sleep. Identical assessment was scheduled annually and more frequently (quarterly) if treatment adjustment was required. Despite lack of differences in ambulatory BP between groups at baseline, subjects ingesting medication at bedtime showed at their last available evaluation significantly lower mean sleep-time BP, higher sleep-time relative BP decline, reduced prevalence of non-dipping (34% versus 62%; p <.001), and higher prevalence of controlled ambulatory BP (62% versus 53%; p <.001). After a median follow-up of 5.6 yrs, subjects ingesting >= 1 BP-lowering medications at
The effect of CD on human health is an emerging issue. Many records link CD with diseases such as cancer, cardiovascular, cognitive impairment and obesity, all of them conducive to premature aging. The amount of sleep has declined by 1.5 h over the past century, accompanied by an important increase in obesity. Shift work, sleep deprivation and exposure to bright light at night increase the prevalence of adiposity. Animal models have shown that mice with Clock gene disruption are prone to developing obesity and MetS. This review summarizes the latest developments with regard to chronobiology and obesity, considering (1) how molecular clocks coordinate metabolism and the specific role of the adipocyte; (2) CD and its causes and pathological consequences; (3) the epidemiological evidence of obesity as a chronobiological illness; and (4) theories of circadian disruption and obesity. Energy intake and expenditure, relevance of sleep, fat intake from a circadian perspective and psychological and genetic aspects of obesity are examined. Finally, ideas about the use of chronobiology in the treatment of obesity are discussed. Such knowledge has the potential to become a valuable tool in the understanding of the relationship between the chronobiology, etiology and pathophysiology of obesity.
Excess caloric intake is strongly associated with the development of increased adiposity, glucose intolerance, insulin resistance, dyslipidemia, and hyperleptinemia (that is the cardiometabolic syndrome). Research efforts have focused attention primarily on the quality (that is nutritional content) and/or quantity of ingested calories as potential causes for diet-induced pathology. Despite growing acceptance that biological rhythms profoundly influence energy homeostasis, little is known regarding how the timing of nutrient ingestion influences development of common metabolic diseases.
To test the hypothesis that the time of day at which dietary fat is consumed significantly influences multiple cardiometabolic syndrome parameters.
We report that mice fed either low- or high-fat diets in a contiguous manner during the 12 h awake/active period adjust both food intake and energy expenditure appropriately, such that metabolic parameters are maintained within a normal physiologic range. In contrast, fluctuation in dietary composition during the active period (as occurs in human beings) markedly influences whole body metabolic homeostasis. Mice fed a high-fat meal at the beginning of the active period retain metabolic flexibility in response to dietary challenges later in the active period (as revealed by indirect calorimetry). Conversely, consumption of high-fat meal at the end of the active phase leads to increased weight gain, adiposity, glucose intolerance, hyperinsulinemia, hypertriglyceridemia, and hyperleptinemia (that is cardiometabolic syndrome) in mice. The latter perturbations in energy/metabolic homeostasis are independent of daily total or fat-derived calories.
The time of day at which carbohydrate versus fat is consumed markedly influences multiple cardiometabolic syndrome parameters.
Relations among circadian rhythms in serum iron, glucagon and insulin and urinary cyclic AMP excretion differ drastically when diurnally active, nocturnally resting human adults consume all daily food for one week as breakfast only and for another week as dinner only - a finding of interest to diverse fields, e.g., for optimizing certain kinds of therapy or for a better utilization of calories.
The objective of this study was to assess a circadian variation of diet-induced thermogenesis (DIT) that could favor weight gain among night workers used to eating a night time snack. Nine young men were given the same mean at 0900, 1700, or 0100. Energy expenditure was measured by indirect calorimetry 1 h before and during the 6 h after the snack. DIT was calculated as the 3 h of energy expenditure above basal metabolic rate. Morning DIT was significantly higher than afternoon DIT (P = 0.04) and night DIT (P = 0.002). Afternoon DIT was higher than night DIT (P = 0.06). We conclude that the time when a meal is consumed affects the thermogenic response and must be considered in the energy balance.
To assess the relationship between feeding pattern and body mass index in free-living humans.
Feeding pattern was assessed from 220 7-day weighed dietary records. 187 records were obtained from three separate existing studies, and reanalysed. These studies contained data on three age groups in the British population; Elderly group (n = 88), Middle-aged group (n = 40), Working age group (n = 59). A separate study of 13-14 year olds living in Croydon was conducted from which 33 usable diet records were collected to produce a fourth, Adolescent group.
'Nibbling' and greater energy intakes at breakfast were associated with a lower body mass index (BMI) in the Adolescent group. In the Middle-aged group, greater energy intakes at breakfast and lower energy intakes during the evening were associated with a lower BMI. However, when diet records which produced unreasonably low energy intakes were removed from the analysis, these relationships disappeared except for energy intakes at breakfast and BMI in the Adolescent group.
It is suggested that the relationship between feeding pattern and BMI observed in the Adolescent and Middle-aged groups was caused by underestimation of 'habitual' energy intake from snacks and the omission of breakfast by females and those who were overweight. The lack of relationship in the Working age group was attributed to the fact that more individuals in this group appeared to report valid diet records. Reported energy intake was directly related to BMI in the Working age group, but was not related to BMI in the other three age groups. It is concluded that feeding pattern is not a major factor in determining BMI in humans. Also, since snacks have a relatively high sugar and low fat composition compared with meals, it is suggested that biased under-reporting of snacks by the obese could produce spurious results from free-living studies which show that obesity is related to the proportion of energy from fat in the diet.
Over the past 40 years, meal skipping and snacking in adults in the United States has increased, and currently most eating occasions occur later in the day than previously. Whether these changes have played a causal role in the obesity epidemic is poorly understood. Observational studies are largely inconclusive due to methodological limitations. Experimental evidence does not support a causal role for eating frequency, or breakfast skipping in weight control. Emerging evidence suggests that eating irregularity and eating later in the day may be detrimental for weight control, but more studies are needed. This article summarizes studies and highlights areas needing attention.
