Article

Original Research Unrestricted Paleolithic Diet is Associated with Unfavorable Changes to Blood Lipids in Healthy Subjects

Authors:
To read the full-text of this research, you can request a copy directly from the authors.

Abstract

International Journal of Exercise Science 7(2) : 128-139, 2014. The Paleolithic (Paleo) diet is one modeled after the perceived food consumption of early human ancestors of the Paleolithic Era, consisting of mainly meat, fish, fruit, vegetables, eggs, and nuts. The purpose of this study was to examine the effects of a Paleo diet on blood lipids, including high-density lipoprotein (HDL), low-density lipoprotein (LDL), non-HDL cholesterol, triglycerides (TG), total cholesterol (TC), and the ratio between TC and HDL (TC/HDL) in a healthy population. Healthy subjects of both genders (24 males, 20 females) were asked to eat an ad libitum Paleo diet for 10 weeks. Prior to the intervention, body weight, body fat percentage (BF%), maximal oxygen consumption (VO2max), TC, TG, HDL, and LDL were measured. These measurements were repeated following 10 weeks of a Paleo diet. As a whole, there was a significant increase in non-HDL (107.1±6.0 mg/dL to 120.2±6.5 mg/dL; P<0.01), LDL (93.1±5.4 mg/dL to 105.6±6.1 mg/dL; P<0.01), TC/HDL (3.0±0.2 to 3.3±0.2; P<0.05), and TC (168.8±5.4 mg/dL to 178.9±6.6 mg/dL; P<0.05) in healthy subjects following a Paleo diet. When stratified into groups based on initial blood lipid levels, deleterious changes were found in those with optimal HDL (82.1±3.2 mg/dL to 68.6±4.8 mg/dL; P<0.05), non-HDL (86.6±3.9 mg/dL to 101.4±4.8 mg/dL; P<0.01), TC (157.2±0.7 to 168.2±0.9 mg/dL; P<0.05), TC/HDL (2.5±0.1 to 2.7±0.1; P<0.05), and LDL (69.1±3.1 mg/dL to 83.5±4.1 mg/dL; P<0.01), whereas those within sub-optimal stratifications showed no significant changes. Subjects also decreased body weight (80.7±2.6 kg to 77.5±2.4 kg; P<0.001) and BF% (24.3±1.2% to 20.7±1.2%; P < 0.05). Our results demonstrate that an ad libitum unrestricted Paleo diet intervention is associated with deleterious changes to blood lipids in healthy subjects, despite concurrent improvements in body composition and cardiorespiratory fitness. Future research should focus on determining recommendations that embrace the positive aspects of the Paleo diet, while minimizing any deleterious impact on blood lipids in a healthy population.

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the authors.

... Initially, weight loss is due to the loss of water weight as this diet is low in carbohydrates. Previous studies suggest that the study participants lost 4-6% of total body weight within 10-12 weeks (63,64). Most of the studies are based on short-term interventions and there is only one study that followed the subjects for over 2 years. ...
... Most of the studies reported the TC reduction properties of this diet while there are mixed results for HDL-c (61,62,64,66). A study was conducted to evaluate the physiological and metabolic impacts of PD in healthy adults. ...
... In another study, healthy subjects followed this dietary intervention for 10 weeks, which resulted in increased LDLc, TC, TC:HDL-c, along with a decline in HDL-c values (64). No significant changes in fasting blood glucose were seen in most studies (65,66). ...
Article
Full-text available
The global prevalence of obesity is alarmingly high and is impacting both developed and underdeveloped countries, beyond the borders of ethnicity, sex, and age. On the other hand, the global interest in dieting has increased, and people are obsessed with certain fad diets, assuming them as a magic bullet for their long-term problems. A fad diet is a popular dietary pattern known to be a quick fix for obesity. These diets are quite appealing due to the proposed claims, but the lack of scientific evidence is a big question mark. Such diets are often marketed with specific claims that defy the basic principles of biochemistry and nutritional adequacy. These diets may have protective effects against obesity and certain chronic diseases like cardiovascular diseases, metabolic syndrome, and certain cancers. Limited evidence exists to support the proposed claims; rather certain studies suggest the negative health consequences of long-term adherence to such dietary patterns. Many fad diets have emerged in the previous few decades. This review article will explore the current evidence related to the health impacts of some most popular diets: Atkins diet, ketogenic diet, Paleolithic diet, Mediterranean diet, vegetarian diet, intermittent fasting and detox diet.
... Many prominent CrossFit athletes advocate adherence to the Paleo diet, which has contributed to a recent boost in the popularity of the diet [55]. Only few studies have examined the effects of a PD with exercise on cardiorespiratory fitness in healthy or unhealthy adults [42][43][44]50,55]. ...
... Many prominent CrossFit athletes advocate adherence to the Paleo diet, which has contributed to a recent boost in the popularity of the diet [55]. Only few studies have examined the effects of a PD with exercise on cardiorespiratory fitness in healthy or unhealthy adults [42][43][44]50,55]. To date, there is no scientific study on the effect of the Paleo diet on professional athletes. ...
... In a few studies, the information about the sex of study participants was not indicated [28,42,51]. Four studies included subjects that had type 2 diabetes mellitus and or were obese [51,52], eleven studies included overweight or obese postmenopausal women [37,[40][41][42][43][44][45][46][47][48][49], one study included subject with hypercholesterolemia [39], one study recruited subjects with ischemic heart disease plus either glucose intolerance or type 2 diabetes [28], one study was conducted in subjects with at least two characteristics of the metabolic syndrome [53], and four studies recruited healthy but inactive adults [18,55,56,71]. We examined the significance of the change in PD and healthy diets (CDs) based on the Nordic Nutrition Recommendation (NNR) [40,45,46,49], the Dutch Health Council [53], the Australian Guide to Healthy Eating (AGHE) [54], the American Diabetes Association (ADA) [52], the American Heart Association (AHA) [39], the Mediterranean diet [28], a conventional low-fat diet (LFD) [41], and the so-called "diabetes diet" [51]. ...
Article
Full-text available
The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance
... Many prominent CrossFit athletes advocate adherence to the Paleo diet, which has contributed to a recent boost in the popularity of the diet [55]. Only few studies have examined the effects of a PD with exercise on cardiorespiratory fitness in healthy or unhealthy adults [42][43][44]50,55]. ...
... Many prominent CrossFit athletes advocate adherence to the Paleo diet, which has contributed to a recent boost in the popularity of the diet [55]. Only few studies have examined the effects of a PD with exercise on cardiorespiratory fitness in healthy or unhealthy adults [42][43][44]50,55]. To date, there is no scientific study on the effect of the Paleo diet on professional athletes. ...
... In a few studies, the information about the sex of study participants was not indicated [28,42,51]. Four studies included subjects that had type 2 diabetes mellitus and or were obese [51,52], eleven studies included overweight or obese postmenopausal women [37,[40][41][42][43][44][45][46][47][48][49], one study included subject with hypercholesterolemia [39], one study recruited subjects with ischemic heart disease plus either glucose intolerance or type 2 diabetes [28], one study was conducted in subjects with at least two characteristics of the metabolic syndrome [53], and four studies recruited healthy but inactive adults [18,55,56,71]. We examined the significance of the change in PD and healthy diets (CDs) based on the Nordic Nutrition Recommendation (NNR) [40,45,46,49], the Dutch Health Council [53], the Australian Guide to Healthy Eating (AGHE) [54], the American Diabetes Association (ADA) [52], the American Heart Association (AHA) [39], the Mediterranean diet [28], a conventional low-fat diet (LFD) [41], and the so-called "diabetes diet" [51]. ...
Article
Full-text available
The aim of this meta-analysis was to review the impact of a Paleolithic diet (PD) on selected health indicators (body composition, lipid profile, blood pressure, and carbohydrate metabolism) in the short and long term of nutrition intervention in healthy and unhealthy adults. A systematic review of randomized controlled trials of 21 full-text original human studies was conducted. Both the PD and a variety of healthy diets (control diets (CDs)) caused reduction in anthropometric parameters, both in the short and long term. For many indicators, such as weight (body mass (BM)), body mass index (BMI), and waist circumference (WC), impact was stronger and especially found in the short term. All diets caused a decrease in total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and triglycerides (TG), albeit the impact of PD was stronger. Among long-term studies, only PD cased a decline in TC and LDL-C. Impact on blood pressure was observed mainly in the short term. PD caused a decrease in fasting plasma (fP) glucose, fP insulin, and homeostasis model assessment of insulin resistance (HOMA-IR) and glycated hemoglobin (HbA1c) in the short run, contrary to CD. In the long term, only PD caused a decrease in fP glucose and fP insulin. Lower positive impact of PD on performance was observed in the group without exercise. Positive effects of the PD on health and the lack of experiments among professional athletes require longer-term interventions to determine the effect of the Paleo diet on athletic performance.
... The consequences of the discrepancies between the diets and lifestyles of Homo sapiens before the agricultural revolution and those during the modern, postindustrial revolution era are referred to as evolutionary discordance, and they have been proposed to account for some of the dramatic increase in chronic disease in the past century (25). To our knowledge, there has been very limited study of this diet reported in the scientific literature, with some indications that it may improve cardiovascular and metabolic biomarkers (26)(27)(28)(29)(30)(31)(32), perhaps similar to or even more so than a Mediterranean diet (28,33). The Mediterranean diet is considered to be one of the healthiest diets for preventing many chronic diseases (34)(35)(36), and it is associated with lower concentrations of biomarkers of inflammation and oxidative stress (37)(38)(39). ...
... To our knowledge, there are few reported studies of a Paleolithic diet pattern in relation to biomarkers of disease risk. Six small pilot trials that examined the effects of a Paleolithic diet on cardiovascular disease risk and glycemic control biomarkers, such as glycated hemoglobin, plasma insulin, blood pressure, and serum TGs and cholesterol (26)(27)(28)(29)(30)(31), generally observed improvements in these markers, although only 3 of these pilot trials had a control group (27)(28)(29). A slightly larger study (n = 70) of the effects of a Paleolithic diet on long-term weight loss found statistically significant greater weight loss at 6 mo in the Paleolithic diet group than in the control group, although the difference mostly dissipated after 24 mo (32). ...
Article
Background: Chronic inflammation and oxidative balance are associated with poor diet quality and risk of cancer and other chronic diseases. A diet-inflammation/oxidative balance association may relate to evolutionary discordance. Objective: We investigated associations between 2 diet pattern scores, the Paleolithic and the Mediterranean, and circulating concentrations of 2 related biomarkers, high-sensitivity C-reactive protein (hsCRP), an acute inflammatory protein, and F2-isoprostane, a reliable marker of in vivo lipid peroxidation. Methods: In a pooled cross-sectional study of 30- to 74-y-old men and women in an elective outpatient colonoscopy population (n= 646), we created diet scores from responses on Willett food-frequency questionnaires and measured plasma hsCRP and F2-isoprostane concentrations by ELISA and gas chromatography-mass spectrometry, respectively. Both diet scores were calculated and categorized into quintiles, and their associations with biomarker concentrations were estimated with the use of general linear models to calculate and compare adjusted geometric means, and via unconditional ordinal logistic regression. Results: There were statistically significant trends for decreasing geometric mean plasma hsCRP and F2-isoprostane concentrations with increasing quintiles of the Paleolithic and Mediterranean diet scores. The multivariable-adjusted ORs comparing those in the highest with those in the lowest quintiles of the Paleolithic and Mediterranean diet scores were 0.61 (95% CI: 0.36, 1.05;P-trend = 0.06) and 0.71 (95% CI: 0.42, 1.20;P-trend = 0.01), respectively, for a higher hsCRP concentration, and 0.51 (95% CI: 0.27, 0.95;P-trend 0.01) and 0.39 (95% CI: 0.21, 0.73;P-trend = 0.01), respectively, for a higher F2-isoprostane concentration. Conclusion: These findings suggest that diets that are more Paleolithic- or Mediterranean-like may be associated with lower levels of systemic inflammation and oxidative stress in humans.
... It even deserved a recent systematic review with meta-analysis on its applicability in metabolic syndrome [12]. However, there have been conflicting results, some noting the positive effects of the Paleolithic diet on reducing the risk of diabetes, cancer, metabolic syndrome, cardiovascular diseases and type 2 diabetes [13,14,12], others mentioning deleterious effects [15], and others proving no effect [16]. ...
Article
Full-text available
Background: The Paleolithic diet has been studied in the scope of prevention and control of chronic noncommunicable diseases (CNCD). The objective of this study was to analyze the influence of the Paleolithic diet on the prevention and control of CNCD in humans, specifically on anthropometric markers, through a systematic review with meta-analysis. Methods: What is the effect of the Paleolithic diet on anthropometric parameters (weight, body mass index and waist circumference) compared to other control diets based on recommendations in adults? We included only randomized studies with humans that used the Paleolithic Diet in the prevention and control of CNCD published in Portuguese, English or Spanish. The search period was until March 2019, in the LILACS, PubMed, Scielo, Science Direct, Medline, Web of Science and Scopus databases. The abstracts were evaluated by two researchers. We found 1224 articles, of which 24 were selected and 11 were included in the meta-analysis. The effect of dietary use on body weight, body mass index and waist circumference was evaluated. Results: The summary of the effect showed a loss of - 3.52 kg in the mean weight (CI 95%: - 5.26; - 1.79; p < 0,001; I2 = 24%) of people who adopted the Paleolithic diet compared to diets based on recommendations. The analysis showed a positive association of adopting the Paleolithic diet in relation to weight loss. The effect was significant on weight, body mass index and waist circumference. Conclusion: The Paleolithic diet may assist in controlling weight and waist circumference and in the management of chronic diseases. However, more randomized clinical studies with larger populations and duration are necessary to prove health benefits. Trial registration: CRD42015027849 .
... A total of 2979 studies were identified by the primary search of the electronic databases, and 1 additional study was found through the hand search of the citations of the included articles and related reviews. We selected 28 eligible studies which were full-text reviewed, and 20 of them were excluded for the following reasons: 1) 7 studies reported no data on our target outcomes (38)(39)(40)(41)(42)(43)(44); 2) 6 studies reported duplicated results which were published in another article (45)(46)(47)(48)(49)(50); 3) 5 studies had no control group (21,29,(51)(52)(53); 4) 1 study assessed the effect of a PD along with exercise (54); and 5) 1 study assessed the acute effect of a PD intake (55). In total, 8 eligible studies were included in the present systematic review and meta-analysis (19,25,30,31,(56)(57)(58)(59). ...
Article
Full-text available
There is some evidence supporting the beneficial effects of a Paleolithic Diet (PD) on cardiovascular disease risk factors. This diet advises consuming lean meat, fish, vegetables, fruits, and nuts and avoiding intake of grains, dairy products, processed foods, and added sugar and salt. This study was performed to assess the effects of a PD on cardiovascular disease risk factors including anthropometric indexes, lipid profile, blood pressure, and inflammatory markers using data from randomized controlled trials. A comprehensive search was performed in the PubMed, Scopus, ISI Web of Science, and Google Scholar databases up to August, 2018. A meta-analysis was performed using a random-effects model to estimate the pooled effect size. Meta-analysis of 8 eligible studies revealed that a PD significantly reduced body weight [weighted mean difference (WMD) = −2.17 kg; 95% CI: −3.48, −0.87 kg], waist circumference (WMD = −2.90 cm; 95% CI: −4.51, −1.28 cm), body mass index (in kg/m 2) (WMD = −1.15; 95% CI: −1.68, −0.62), body fat percentage (WMD = −1.38%; 95% CI: −2.08%, −0.67%), systolic (WMD = −4.24 mm Hg; 95% CI: −7.11, −1.38 mm Hg) and diastolic (WMD = −2.95 mm Hg; 95% CI: −4.72, −1.18 mm Hg) blood pressure, and circulating concentrations of total cholesterol (WMD = −0.22 mg/dL; 95% CI: −0.42, −0.03 mg/dL), TGs (WMD = −0.23 mg/dL; 95% CI: −0.46, −0.01 mg/dL), LDL cholesterol (WMD = −0.13 mg/dL; 95% CI: −0.25, −0.01 mg/dL), and C-reactive protein (CRP) (WMD = −0.41 mg/L; 95% CI: −0.81, −0.008 mg/L) and also significantly increased HDL cholesterol (WMD = 0.05 mg/dL; 95% CI: 0.005, 0.10 mg/dL). However, sensitivity analysis revealed that the overall effects of a PD on lipid profile, blood pressure, and circulating CRP concentrations were significantly influenced by removing some studies, hence the results must be interpreted with caution. Although the present meta-analysis revealed that a PD has favorable effects on cardiovascular disease risk factors, the evidence is not conclusive and more well-designed trials are still needed. Adv Nutr 2019;0:1-13.
... Previous research on the Paleolithic diet has examined its impact on cardiovascular, anthropometric and metabolic outcomes (1)(2)(3)(4)(5)(6)(7)(8)(9) . The elimination of cereals, legumes and dairy products from the Paleolithic diet means food patterns are likely to change significantly, yet there is little research on the changes in intake from the core food groups (4,5,10) . ...
Article
The Paleolithic diet excludes two major sources of fibre, grains and legumes. However, it is not known whether this results in changes to resistant starch (RS) consumption. Serum trimethylamine- N -oxide (TMAO) is produced mainly from colonic fermentation and hepatic conversion of animal protein and is implicated in CVD, but changes in RS intake may alter concentrations. We aimed to determine whether intake of RS and serum concentrations of TMAO varied in response to either the Paleolithic or the Australian Guide to Healthy Eating (AGHE) diets and whether this was related to changes in food group consumption. A total of thirty-nine women (mean age 47 ( sd 13) years, BMI 27 ( sd 4) kg/m ² ) were randomised to AGHE ( n 17) or Paleolithic diets ( n 22) for 4 weeks. Serum TMAO concentrations were measured using liquid chromatography–MS; food groups, fibre and RS intake were estimated from weighed food records. The change in TMAO concentrations between groups (Paleolithic 3·39 μ mv . AGHE 1·19 μ m , P = 0·654) did not reach significance despite greater red meat and egg consumption in the Paleolithic group (0·65 serves/d; 95 % CI 0·2, 1·1; P <0·01, and 0·22 serves/d; 95 % CI 0·1, 0·4, P <0·05, respectively). RS intake was significantly lower on the Paleolithic diet ( P <0·01) and was not associated with TMAO concentrations. However, the limited data for RS and the small sample size may have influenced these findings. While there were no significant changes in TMAO concentrations, increased meat consumption and reduced RS intake warrant further research to examine the markers of gastrointestinal health of Paleolithic diet followers and to update Australian food databases to include additional fibre components.
... Eine Auswertung derselben Daten ergab ein ähnliches Muster für den Fettgehalt und die damit assoziierte Insulinsensitivität der Leber [84]. 2014 äußerte eine Gruppe amerikanischer Sportwissenschaftler Bedenken hinsichtlich des Sicherheitsprofils einer Paläoernäh-rung innerhalb einer hochintensiven Crossfit-Trainingsgruppe [85]. Nach einer 10-wöchigen Intervention einer ad libitum verzehrten Steinzeiternährung mit 44 Freiwilligen ohne Kontrollgruppe wurde die LDL-Fraktion innerhalb des Lipidprofils im Mittel leicht aber signifikant erhöht gemessen. ...
Article
Background: Many concepts try to explain the current rise in the chronic non-communicable diseases. Within the framework of evolutionary medicine there is a common explanation for these diseases in the form of an insufficient adaption to the modern lifestyle, which also reflects in the word “diseases of civilization”. Nutrition plays a key role within this framework. Accordingly, the terms “Paleolithic diet”, “Stone Age diet” or simply “Paleo diet” have been introduced to refer to a diet that tries to mimic human dietary behaviors during the Old Stone Age (Paleolithic) era, which chronologically spans the majority of human existence. Because the Paleo diet is not only becoming more popular among consumers, but also receives increased attention from the international scientific community, the goal of this review is to comprehensively summarize the background, principles and scientific evaluation of the Paleo diet for the German-speaking part. Materials and Methods: Based on anthropological and ethnographic studies, supplemented with physiological insights, a short overview of the evolution of the human diet during the Old Stone Age is given. From these insights the principles of a modern Paleo diet are derived. All clinical studies published to date using a Paleo diet as an intervention have been shortly described and evaluated. Finally, the Paleo diet is discussed within the broader context of a modern evolutionary medicine that primarily aims at preventing the chronic non-communicable diseases. Results: Although only studies with small sample sizes and methodological shortcomings have been published, they nevertheless have consistently shown that a Paleolithic diet is superior to other diets, also those regarded as wholesome. The largest evidence supports a beneficial effect on coronary risk factors, while beneficial effects on autoimmune diseases seem probable. Conclusion: A Paleolithic diet appears suitable for the treatment of coronary diseases, and probably also autoimmune disorders. Compliance to the diet is facilitated by its intuitive analogy to a “species-appropriate” diet.
Article
The paleo diet is popular among the general population due to promoted weight loss and disease prevention benefits. We examined the effectiveness of a self-administered paleo diet in improving cardiometabolic disease risk factors. Overweight, physically inactive but otherwise healthy adults (males = 4, females = 3, age 32.7 ± 4.9 years, body mass index [BMI] 29.4 ± 2.4 kg/m ² ) habitually eating a traditional Western diet (1853.4 ± 441.2 kcal; 34.0% carbohydrate; 41.4% fat; 19.2% protein) completed an ad libitum self-administered paleo diet for 8 weeks. Height, weight, blood pressure, and a fasting blood sample were collected pre– and post–paleo dietary intervention. Blood samples were analyzed for fasting cardiometabolic disease biomarkers—including brain-derived neurotropic factor (BDNF), fibroblast growth factor (FGF) 21, and leptin. After 8 weeks, body mass (−5.3 kg, P = .008), BMI (−1.7 kg/m ² , P = .002), serum leptin (−56.2%, P = .012), serum FGF21 (−26.7%, P = .002), and serum BDNF (−25.8%, P = .045) significantly decreased. Systolic and diastolic blood pressure were unchanged following the paleo dietary intervention ( P > .05). Average energy intake (−412.6 kcal, P = .016) significantly decreased with the paleo dietary intervention mostly due to a reduction in carbohydrate consumption (−69.2 g; P = .003). An 8-week self-administered paleo dietary intervention was effective in improving cardiometabolic disease risk factors in a healthy, physically inactive overweight adult population.
Article
Full-text available
Every 4 years, approximately 10,000 athletes participate in the Olympic Games. These athletes have dedicated several years of physical training to achieve the best possible performance on a given day. Their preparation has been supported by expert coaches and an army of sport scientists, whose overall responsibility is to ensure that the athletes are in peak condition for their event. Although every athlete prepares specifically for the unique physiological challenges of their event, all athletes have one common characteristic: they are Homo sapiens. They share a unique genome, which is the result of evolutionary forces beyond their individual control. Although studies on the influence of different genetic polymorphisms on selected athletic events have been proven to be of limited utility, a body of evidence-from molecular biology to whole-body measures-suggests that training adaptations are enhanced when the stimulus closely resembles the activity pattern of human ancestors. Because genetic evolutionary changes occur slowly in Homo sapiens, and the traditional physical activity and dietary patterns of Homo sapiens have undergone rapid and dramatic changes in previous centuries, we propose that modern humans are physiologically better adapted to training modes and nutritional strategies similar to the ones that their hominid ancestors evolved on, rather than those supported by modern societies. Such an ancestral pattern was mainly characterized by the prevalence of daily bouts of prolonged, low-intensity, aerobic-based activities interspersed with periodic, short-duration, high-intensity bursts of activity. On some occasions, such activity patterns were undertaken with low carbohydrate availability. Specific activities that enhanced strength and power were typically performed after aerobic activities. We present scientific evidence to support the appropriateness of this model, and we propose that future studies should address this hypothesis in a multitude of different sporting activities, by assessing the genetic responses to and performance-based outcomes of different training stimuli. Such information would provide data on which sport scientists and coaches could better prepare athletes and manage their training process.
Article
Full-text available
The primary purpose of this study was to investigate the effects of high-intensity exercise training under relatively equal energy expenditure on whole body fat and abdominal fat loss, and cardiorespiratory fitness. Twenty-two untrained middle-aged Korean females were randomized into one of the following groups: control, low-intensity training group (LI), and high-intensity training group (HI). Subjects completed 14 weeks of training at 50% maximal oxygen consumption (LI) or 70% maximal oxygen consumption (HI) with the volume of exercise equated relative to kilograms of body weight. Weekly exercise volumes were 13.5 METs⋅h/week for the first 4 weeks, 18 METs⋅h/week for next 5 weeks, and 22.5 METs⋅h/week for the final 5 weeks. Data were analyzed using 2-way repeated measures ANOVA with post hoc test, using Bonferroni's correction. HI showed significant reductions in fat mass (p < 0.05), total abdominal fat (p < 0.01), and subcutaneous abdominal fat (p < 0.01). LI reduced total abdominal fat (p < 0.05), but there were no other significant changes found in the control or LI groups. Maximal oxygen consumption was enhanced in both HI and LI with no significant group difference. High-density lipoprotein cholesterol increased significantly in HI (p < 0.05). IL-6, C-reactive protein, TNF-α, and other blood lipids were unaltered following training. Results indicate that high-intensity exercise training is more beneficial in whole body and abdominal fat loss; however, cardiorespiratory enhancement shows a dose-response relationship with weekly exercise volume. It is suggested that 14 weeks of aerobic exercise training at either high- or low-intensity is not sufficient enough to induce changes in levels of inflammatory proteins.
Article
Full-text available
We found marked improvement of glucose tolerance and lower dietary energy intake in ischemic heart disease (IHD) patients after advice to follow a Paleolithic diet, as compared to a Mediterranean-like diet. We now report findings on subjective ratings of satiety at meals and data on the satiety hormone leptin and the soluble leptin receptor from the same study. Twenty-nine male IHD patients with impaired glucose tolerance or diabetes type 2, and waist circumference > 94 cm, were randomized to ad libitum consumption of a Paleolithic diet (n = 14) based on lean meat, fish, fruit, vegetables, root vegetables, eggs, and nuts, or a Mediterranean-like diet (n = 15) based on whole grains, low-fat dairy products, vegetables, fruit, fish, and oils and margarines during 12 weeks. In parallel with a four day weighed food record the participants recorded their subjective rating of satiety. Satiety Quotients were calculated, as the intra-meal quotient of change in satiety during meal and consumed energy or weight of food and drink for that specific meal. Leptin and leptin receptor was measured at baseline and after 6 and 12 weeks. Free leptin index was calculated as the ratio leptin/leptin receptor. The Paleolithic group were as satiated as the Mediterranean group but consumed less energy per day (5.8 MJ/day vs. 7.6 MJ/day, Paleolithic vs. Mediterranean, p = 0.04). Consequently, the quotients of mean change in satiety during meal and mean consumed energy from food and drink were higher in the Paleolithic group (p = 0.03). Also, there was a strong trend for greater Satiety Quotient for energy in the Paleolithic group (p = 0.057). Leptin decreased by 31% in the Paleolithic group and by 18% in the Mediterranean group with a trend for greater relative decrease of leptin in the Paleolithic group. Relative changes in leptin and changes in weight and waist circumference correlated significantly in the Paleolithic group (p < 0.001) but not in the Mediterranean group. Changes in leptin receptor and free leptin index were not significant. A Paleolithic diet is more satiating per calorie than a Mediterranean-like diet. ClinicalTrials.gov NCT00419497.
Article
Full-text available
European Paleolithic subsistence is assumed to have been largely based on animal protein and fat, whereas evidence for plant consumption is rare. We present evidence of starch grains from various wild plants on the surfaces of grinding tools at the sites of Bilancino II (Italy), Kostenki 16-Uglyanka (Russia), and Pavlov VI (Czech Republic). The samples originate from a variety of geographical and environmental contexts, ranging from northeastern Europe to the central Mediterranean, and dated to the Mid-Upper Paleolithic (Gravettian and Gorodtsovian). The three sites suggest that vegetal food processing, and possibly the production of flour, was a common practice, widespread across Europe from at least ~30,000 y ago. It is likely that high energy content plant foods were available and were used as components of the food economy of these mobile hunter-gatherers.
Article
Full-text available
The weakening of the cardiovascular system associated with aging could be countered by increasing levels of physical activity and functional fitness. However, inconsistent findings have been found, and the variety of characteristics of exercise used in previous studies may partly explain that inconsistent results. To investigate the training effect of sixteen weeks of moderate intensity, progressive aerobic and strength-based training on metabolic health of older women and men. Sixty three sedentary individuals (mean (SD) age 76 (8) years) were randomly assigned to control (n = 31) or exercising (n = 32) groups. The training group was separated to aerobic (n = 18) or strength-based (n = 14). Training took place three times a week. Subjects agreed not to change their diet or lifestyle over the experimental period. Exercising group attained after treatment significant differences on body weight, waist circumference, body mass index, diastolic blood pressure, triglycerides, total cholesterol, HDL-cholesterol, LDL-cholesterol, total cholesterol/HDL-cholesterol relationship, high sensitivity C-reactive protein, and 6-minute walk distance. The control group only had significant differences on waist circumference. The training programs produced significant benefits on metabolic health indicators of sedentary older women and men.
Article
Full-text available
Omentin-1 is a newly discovered protein expressed and secreted from visceral adipose tissue that increases insulin sensitivity.We examined the effects of 12 weeks of aerobic training on serum omentin-1 concentrations together with cardiovascular risk factors in overweight and obese men. Eighteen overweight and obese participants (age 43.1 ± 4.7 years, BMI ≥ 25 kg . m ⁻² ) were assigned to exercise training (n = 9) and control (n = 9) groups. A matched control group of normal weight participants (n = 8; age 42.2 ± 3.8 years, BMI < 25 kg . m ⁻² ) were also recruited for baseline comparison. The obese exercise group participated in 12 weeks of progressive aerobic training 5 days a week. Measures of serum omentin-1, insulin resistance, lipid profiles, blood pressure, and body composition were obtained before and after the 12 weeks. At baseline, normal weight participants had significantly higher serum omentin-1 concentrations than overweight and obese participants, and there were inverse correlations between omentin-1 and each of waist circumference, fasting glucose, insulin resistance, total cholesterol,triglyceride, and systolic blood pressure (P < 0 .05). After the aerobic training, waist circumference, percent body fat, fasting glucose, insulin resistance, triglyceride, total cholesterol, low-density lipoprotein cholesterol, and systolic blood pressure were all significantly decreased (P < 0.05). In contrast, serum omentin-1 concentration was significantly increased after the aerobic programme (P < 0.05), and correlated with changes in insulin resistance (r = − 0.67, P= 0.04), glucose (r = − 0.65, P = 0.05), waist circumference (r = −70, P = 0.03), and aerobic fitness r = −.68, P = 0.04). Aerobic training resulted in an improvement in cardiometabolic risk factors in obese participants, and this improvement was accompanied by increased omentin-1 concentrations.
Article
Full-text available
The health effects of milk and dairy food consumption would best be determined in randomised controlled trials. No adequately powered trial has been reported and none is likely because of the numbers required. The best evidence comes, therefore, from prospective cohort studies with disease events and death as outcomes. Medline was searched for prospective studies of dairy food consumption and incident vascular disease and Type 2 diabetes, based on representative population samples. Reports in which evaluation was in incident disease or death were selected. Meta-analyses of the adjusted estimates of relative risk for disease outcomes in these reports were conducted. Relevant case-control retrospective studies were also identified and the results are summarised in this article. Meta-analyses suggest a reduction in risk in the subjects with the highest dairy consumption relative to those with the lowest intake: 0.87 (0.77, 0.98) for all-cause deaths, 0.92 (0.80, 0.99) for ischaemic heart disease, 0.79 (0.68, 0.91) for stroke and 0.85 (0.75, 0.96) for incident diabetes. The number of cohort studies which give evidence on individual dairy food items is very small, but, again, there is no convincing evidence of harm from consumption of the separate food items. In conclusion, there appears to be an enormous mis-match between the evidence from long-term prospective studies and perceptions of harm from the consumption of dairy food items.
Article
Full-text available
Our aim was to compare the effects of a Paleolithic ('Old Stone Age') diet and a diabetes diet as generally recommended on risk factors for cardiovascular disease in patients with type 2 diabetes not treated with insulin. In a randomized cross-over study, 13 patients with type 2 diabetes, 3 women and 10 men, were instructed to eat a Paleolithic diet based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts; and a Diabetes diet designed in accordance with dietary guidelines during two consecutive 3-month periods. Outcome variables included changes in weight, waist circumference, serum lipids, C-reactive protein, blood pressure, glycated haemoglobin (HbA1c), and areas under the curve for plasma glucose and plasma insulin in the 75 g oral glucose tolerance test. Dietary intake was evaluated by use of 4-day weighed food records. Study participants had on average a diabetes duration of 9 years, a mean HbA1c of 6,6% units by Mono-S standard and were usually treated with metformin alone (3 subjects) or metformin in combination with a sulfonylurea (3 subjects) or a thiazolidinedione (3 subjects). Mean average dose of metformin was 1031 mg per day. Compared to the diabetes diet, the Paleolithic diet resulted in lower mean values of HbA1c (-0.4% units, p = 0.01), triacylglycerol (-0.4 mmol/L, p = 0.003), diastolic blood pressure (-4 mmHg, p = 0.03), weight (-3 kg, p = 0.01), BMI (-1 kg/m2, p = 0.04) and waist circumference (-4 cm, p = 0.02), and higher mean values of high density lipoprotein cholesterol (+0.08 mmol/L, p = 0.03). The Paleolithic diet was mainly lower in cereals and dairy products, and higher in fruits, vegetables, meat and eggs, as compared with the Diabetes diet. Further, the Paleolithic diet was lower in total energy, energy density, carbohydrate, dietary glycemic load, saturated fatty acids and calcium, and higher in unsaturated fatty acids, dietary cholesterol and several vitamins. Dietary GI was slightly lower in the Paleolithic diet (GI = 50) than in the Diabetic diet (GI = 55). Over a 3-month study period, a Paleolithic diet improved glycemic control and several cardiovascular risk factors compared to a Diabetes diet in patients with type 2 diabetes.
Article
Full-text available
The contemporary American diet figures centrally in the pathogenesis of numerous chronic diseases-'diseases of civilization'. We investigated in humans whether a diet similar to that consumed by our preagricultural hunter-gatherer ancestors (that is, a paleolithic type diet) confers health benefits. We performed an outpatient, metabolically controlled study, in nine nonobese sedentary healthy volunteers, ensuring no weight loss by daily weight. We compared the findings when the participants consumed their usual diet with those when they consumed a paleolithic type diet. The participants consumed their usual diet for 3 days, three ramp-up diets of increasing potassium and fiber for 7 days, then a paleolithic type diet comprising lean meat, fruits, vegetables and nuts, and excluding nonpaleolithic type foods, such as cereal grains, dairy or legumes, for 10 days. Outcomes included arterial blood pressure (BP); 24-h urine sodium and potassium excretion; plasma glucose and insulin areas under the curve (AUC) during a 2 h oral glucose tolerance test (OGTT); insulin sensitivity; plasma lipid concentrations; and brachial artery reactivity in response to ischemia. Compared with the baseline (usual) diet, we observed (a) significant reductions in BP associated with improved arterial distensibility (-3.1+/-2.9, P=0.01 and +0.19+/-0.23, P=0.05);(b) significant reduction in plasma insulin vs time AUC, during the OGTT (P=0.006); and (c) large significant reductions in total cholesterol, low-density lipoproteins (LDL) and triglycerides (-0.8+/-0.6 (P=0.007), -0.7+/-0.5 (P=0.003) and -0.3+/-0.3 (P=0.01) mmol/l respectively). In all these measured variables, either eight or all nine participants had identical directional responses when switched to paleolithic type diet, that is, near consistently improved status of circulatory, carbohydrate and lipid metabolism/physiology. Even short-term consumption of a paleolithic type diet improves BP and glucose tolerance, decreases insulin secretion, increases insulin sensitivity and improves lipid profiles without weight loss in healthy sedentary humans.
Article
Full-text available
To determine the relation between cardiorespiratory fitness, as determined with the Canadian Aerobic Fitness Test (CAFT), and selected risk factors for coronary heart disease (CHD) in a Canadian population. Cross-sectional study. On the basis of age-specific and sex-specific national percentile scores, subjects were classified as being in the low-fitness, moderate-fitness or high-fitness category according to maximum oxygen consumption (VO2 max) predicted from performance on the CAFT. A total of 4082 male and 1205 female Canadian federal public servants aged 30 to 59 years who participated in a voluntary fitness testing program between 1984 and 1991. Body composition (body mass index, triceps skinfold thickness, sum of four skinfold measurements, predicted percentage of body fat and waist-hip ratio), blood lipid levels (total cholesterol, triglycerides, high-density lipoprotein cholesterol [HDL-C], low-density lipoprotein cholesterol and ratio of total cholesterol to HDL-C) and hemodynamic measurements (heart rate and blood pressure at rest and during exercise and predicted VO2 max). For both men and women the mean anthropometric measurements, blood lipid levels and blood pressure measurements at rest and after exercise were significantly associated with fitness category (p less than 0.05). In both men and women a higher level of aerobic fitness, as defined by VO2 max predicted from performance on the CAFT, is associated with a more favourable CHD risk profile. The results support the use of VO2 max predicted from performance on the CAFT as a valid procedure for classifying people according to fitness level.
Article
Full-text available
The aim of this study was to produce a validated satiety index of common foods. Isoenergetic 1000 kJ (240 kcal) servings of 38 foods separated into six food categories (fruits, bakery products, snack foods, carbohydrate-rich foods, protein-rich foods, breakfast cereals) were fed to groups of 11-13 subjects. Satiety ratings were obtained every 15 min over 120 min after which subjects were free to eat ad libitum from a standard range of foods and drinks. A satiety index (SI) score was calculated by dividing the area under the satiety response curve (AUC) for the test food by the group mean satiety AUC for white bread and multiplying by 100. Thus, white bread had an SI score of 100% and the SI scores of the other foods were expressed as a percentage of white bread. There were significant differences in satiety both within and between the six food categories. The highest SI score was produced by boiled potatoes (323 +/- 51%) which was seven-fold higher than the lowest SI score of the croissant (47 +/- 17%). Most foods (76%) had an SI score greater than or equal to white bread. The amount of energy eaten immediately after 120 min correlated negatively with the mean satiety AUC responses (r = -0.37, P < 0.05, n = 43) thereby supporting the subjective satiety ratings. SI scores correlated positively with the serving weight of the foods (r = 0.66, P < 0.001, n = 38) and negatively with palatability ratings (r = -0.64, P < 0.001, n = 38). Protein, fibre, and water contents of the test foods correlated positively with SI scores (r = 0.37, P < 0.05, n = 38; r = 0.46, P < 0.01; and r = 0.64, P < 0.001; respectively) whereas fat content was negatively associated (r = -0.43, P < 0.01). The results show that isoenergetic servings of different foods differ greatly in their satiating capacities. This is relevant to the treatment and prevention of overweight and obesity.
Article
Full-text available
Recent data from this laboratory demonstrate that increasing adipocyte intracellular Ca(2+) results in a coordinated stimulation of lipogenesis and inhibition of lipolysis. We have also noted that increasing dietary calcium of obese patients for 1 year resulted in a 4.9 kg loss of body fat (P<0.01). Accordingly, we tested the possibility that calcitrophic hormones may act on adipocytes to increase Ca(2+) and lipid metabolism by measuring the effects of 1, 25-(OH)(2)-D in primary cultures of human adipocytes, and found significant, sustained increases in intracellular Ca(2+) and a corresponding marked inhibition of lipolysis (EC(50) approximately 50 pM; P<0.001), suggesting that dietary calcium could reduce adipocyte mass by suppressing 1,25-(OH)(2)-D. To test this hypothesis, we placed transgenic mice expressing the agouti gene specifically in adipocytes on a low (0.4%) Ca/high fat/high sucrose diet either unsupplemented or with 25 or 50% of the protein replaced by non-fat dry milk or supplemented to 1.2% Ca with CaCO(3) for 6 wk. Weight gain and fat pad mass were reduced by 26-39% by the three high calcium diets (P<0.001). The high calcium diets exerted a corresponding 51% inhibition of adipocyte fatty acid synthase expression and activity (P<0.002) and stimulation of lipolysis by 3. 4- to 5.2-fold (P<0.015). This concept of calcium modulation of adiposity was further evaluated epidemiologically in the NHANES III data set. After controlling for energy intake, relative risk of being in the highest quartile of body fat was set to 1.00 for the lowest quartile of Ca intake and was reduced to 0.75, 0.40, and 0.16 for the second, third, and fourth quartiles, respectively, of calcium intake for women (n=380;P<0.0009); a similar inverse relationship was also noted in men (n=7114; P<0.0006). Thus, increasing dietary calcium suppresses adipocyte intracellular Ca(2+) and thereby modulates energy metabolism and attenuates obesity risk.
Article
Full-text available
It is not clear whether varying the protein-to-carbohydrate ratio of weight-loss diets benefits body composition or metabolism. The objective was to compare the effects of 2 weight-loss diets differing in protein-to-carbohydrate ratio on body composition, glucose and lipid metabolism, and markers of bone turnover. A parallel design included either a high-protein diet of meat, poultry, and dairy foods (HP diet: 27% of energy as protein, 44% as carbohydrate, and 29% as fat) or a standard-protein diet low in those foods (SP diet: 16% of energy as protein, 57% as carbohydrate, and 27% as fat) during 12 wk of energy restriction (6-6.3 MJ/d) and 4 wk of energy balance ( approximately 8.2 MJ/d). Fifty-seven overweight volunteers with fasting insulin concentrations > 12 mU/L completed the study. Weight loss (7.9 +/- 0.5 kg) and total fat loss (6.9 +/- 0.4 kg) did not differ between diet groups. In women, total lean mass was significantly (P = 0.02) better preserved with the HP diet (-0.1 +/- 0.3 kg) than with the SP diet (-1.5 +/- 0.3 kg). Those fed the HP diet had significantly (P < 0.03) less glycemic response at weeks 0 and 16 than did those fed the SP diet. After weight loss, the glycemic response decreased significantly (P < 0.05) more in the HP diet group. The reduction in serum triacylglycerol concentrations was significantly (P < 0.05) greater in the HP diet group (23%) than in the SP diet group (10%). Markers of bone turnover, calcium excretion, and systolic blood pressure were unchanged. Replacing carbohydrate with protein from meat, poultry, and dairy foods has beneficial metabolic effects and no adverse effects on markers of bone turnover or calcium excretion.
Article
Full-text available
Diets with higher protein (1.5 g x kg(-1) x d(-1)) and reduced carbohydrates (120 to 200 g/d) appear to enhance weight loss due to a higher loss of body fat and reduced loss of lean body mass. While studies of prolonged use of moderate protein diets are not available, short-term studies report beneficial effects associated with increased satiety, increased thermogenesis, sparing of muscle protein loss, and enhanced glycemic control. Combined impacts of a moderate protein diet are likely derived from lower carbohydrates resulting in lower postprandial increase in blood glucose and lower insulin response, and higher protein providing increased BCAA leucine levels and gluconeogenic substrates. A key element in the diet appears to be the higher intake of BCAA leucine with unique regulatory actions on muscle protein synthesis, modulation of the insulin signal, and sparing of glucose use by stimulation of the glucose-alanine cycle. This review focuses on the contributions of leucine and the BCAA to regulation of muscle protein synthesis and glycemic control.
Article
Full-text available
Claims about the merits or risks of carbohydrate (CHO) vs. protein for weight loss diets are extensive, yet the ideal ratio of dietary carbohydrate to protein for adult health and weight management remains unknown. This study examined the efficacy of two weight loss diets with modified CHO/protein ratios to change body composition and blood lipids in adult women. Women (n = 24; 45 to 56 y old) with body mass indices >26 kg/m(2) were assigned to either a CHO Group consuming a diet with a CHO/protein ratio of 3.5 (68 g protein/d) or a Protein Group with a ratio of 1.4 (125 g protein/d). Diets were isoenergetic, providing 7100 kJ/d, and similar amounts of fat ( approximately 50 g/d). After consuming the diets for 10 wk, the CHO Group lost 6.96 +/- 1.36 kg body weight and the Protein Group lost 7.53 +/- 1.44 kg. Weight loss in the Protein Group was partitioned to a significantly higher loss of fat/lean (6.3 +/- 1.2 g/g) compared with the CHO Group (3.8 +/- 0.9). Both groups had significant reductions in serum cholesterol ( approximately 10%), whereas the Protein Group also had significant reductions in triacylglycerols (TAG) (21%) and the ratio of TAG/HDL cholesterol (23%). Women in the CHO Group had higher insulin responses to meals and postprandial hypoglycemia, whereas women in the Protein Group reported greater satiety. This study demonstrates that increasing the proportion of protein to carbohydrate in the diet of adult women has positive effects on body composition, blood lipids, glucose homeostasis and satiety during weight loss.
Article
Full-text available
Amino acids interact with glucose metabolism both as carbon substrates and by recycling glucose carbon via alanine and glutamine; however, the effect of protein intake on glucose homeostasis during weight loss remains unknown. This study tests the hypothesis that a moderate increase in dietary protein with a corresponding reduction of carbohydrates (CHO) stabilizes fasting and postprandial blood glucose and insulin during weight loss. Adult women (n = 24; >15% above ideal body weight) were assigned to either a Protein Group [protein: 1.6 g/(kg. d); CHO <40% of energy] or CHO Group [protein: 0.8 g/(kg. d); CHO >55%]. Diets were equal in energy (7100 kJ/d) and fat (50 g/d). After 10 wk, the Protein Group lost 7.53 +/- 1.44 kg and the CHO Group lost 6.96 +/- 1.36 kg. Plasma amino acids, glucose and insulin were determined after a 12-h fast and 2 h after a 1.67 MJ test meal containing either 39 g CHO, 33 g protein and 13 g fat (Protein Group) or 57 g CHO, 12 g protein and 14 g fat (CHO Group). After 10 wk, subjects in the CHO Group had lower fasting (4.34 +/- 0.10 vs 4.89 +/- 0.11 mmol/L) and postprandial blood glucose (3.77 +/- 0.14 vs. 4.33 +/- 0.15 mmol/L) and an elevated insulin response to meals (207 +/- 21 vs. 75 +/- 18 pmol/L). This study demonstrates that consumption of a diet with increased protein and a reduced CHO/protein ratio stabilizes blood glucose during nonabsorptive periods and reduces the postprandial insulin response.
Article
Full-text available
Moderate to high levels of cardiorespiratory fitness (CRF) are associated with a lower risk of the metabolic syndrome and all-cause mortality. Unknown is whether CRF attenuates health risk for a given level of abdominal visceral fat, subcutaneous fat, and/or waist circumference. The sample studied comprised 297 apparently healthy men with available computed tomography or magnetic resonance imaging scans of the abdomen, metabolic data, and maximal treadmill exercise test results. Men were categorized into low-CRF (20%, n = 56), moderate-CRF (40%, n = 94), and high-CRF (40%, n = 147) groups based on age and exercise test results. All analyses were adjusted for age. For a given level of waist circumference, visceral fat, or subcutaneous fat, the high-CRF group had lower triglyceride levels (P < 0.05) and higher HDL cholesterol levels than the low- or moderate-CRF groups. There was a significant group interaction (P < 0.01) for blood pressure, indicating that the increase in blood pressure per unit increase in visceral fat or waist circumference was greater in men in the low-CRF group compared with the high-CRF group. The relative risks of having the metabolic syndrome were 1.8 (95% CI 1.0-3.1) and 1.6 (0.9-2.7) times higher in the low- and moderate-CRF groups, respectively, compared with the high-CRF group after adjusting for age, visceral fat, and subcutaneous fat (P for trend = 0.06). High levels of CRF are associated with a substantial reduction in health risk for a given level of visceral and subcutaneous fat.
Article
Full-text available
Little is known about the relative effectiveness of calcium supplementation from food or pills with or without vitamin D supplementation for bone mass accrual during the rapid growth period. The purpose was to examine the effects of both food-based and pill supplements of calcium and vitamin D on bone mass and body composition in girls aged 10-12 y. This placebo-controlled intervention trial randomly assigned 195 healthy girls at Tanner stage I-II, aged 10-12 y, with dietary calcium intakes <900 mg/d to 1 of 4 groups: calcium (1000 mg) + vitamin D3 (200 IU), calcium (1000 mg), cheese (1000 mg calcium), and placebo. Primary outcomes were bone indexes of the hip, spine, and whole body by dual-energy X-ray absorptiometry and of the radius and tibia by peripheral quantitative computed tomography. With the use of intention-to-treat or efficacy analysis, calcium supplementation with cheese resulted in a higher percentage change in cortical thickness of the tibia than did placebo, calcium, or calcium + vitamin D treatment (P = 0.01, 0.038, and 0.004, respectively) and in higher whole-body bone mineral density than did placebo treatment (P = 0.044) when compliance was >50%. With the use of a hierarchical linear model with random effects to control for growth velocity, these differences disappeared. Increasing calcium intake by consuming cheese appears to be more beneficial for cortical bone mass accrual than the consumption of tablets containing a similar amount of calcium. Diverse patterns of growth velocity may mask the efficacy of supplementation in a short-term trial of children transiting through puberty.
Article
Full-text available
Unlabelled: A number of reviewers have examined studies investigating the relationship between coronary heart disease and stroke prior to 2000. Since then, several key studies have been published. Five studies have examined the relationship between wholegrain consumption, coronary heart disease (CHD) and cardiovascular (CVD) disease and found protection for either or both diseases. The researchers concluded that a relationship between wholegrain intake and CHD is seen with at least a 20% and perhaps a 40% reduction in risk for those who eat wholegrain food habitually vs those who eat them rarely. Notwithstanding the fact that fibre is an important component of wholegrains, many studies have not shown an independent effect of fibre alone on CHD events. Thus in terms of CHD prevention, fibre is best obtained from wholegrain sources. Wholegrain products have strong antioxidant activity and contain phytoestrogens, but there is insufficient evidence to determine whether this is beneficial in CHD prevention. Soluble fibre clearly lowers cholesterol to a small but significant degree and one would expect that this would reduce CHD events. There have been a small number of epidemiological studies showing soy consumption is associated with lower rates of heart disease. Countering the positive evidence for wholegrain and legume intake has been the Nurses Health Study in 2000 that showed women who were overweight or obese consuming a high glycaemic load (GL) diet doubled their relative risk of CHD compared with those consuming a low GL diet. Although the literature relating GL with CHD events is somewhat mixed, the relationship with risk factors such as HDL cholesterol, triglyceride and C reactive protein is relatively clear. Thus, carbohydrate-rich foods should be wholegrain and, if they are not, then the lowest glycaemic index (GI) product should be used. Promotion of carbohydrate foods should be focused on wholegrain cereals because these have proven to be associated with health benefits. There is insufficient evidence about whether the addition of other components of wholegrains such as polyphenolics or minerals (such as magnesium or zinc) would improve the health benefits of refined grain foods and this needs investigation. Whether adding bran to refined carbohydrate foods can improve the situation is also not clear, and it was found that added bran lowered heart disease risk in men by 30%. This persisted after full adjustment (including GL) suggesting, at least in men, that fibre may be more important than GI. Thus there are two messages: The intake of wholegrain foods clearly protects against heart disease and stroke but the exact mechanism is not clear. Fibre, magnesium, folate and vitamins B6 and vitamin E may be important. The intake of high GI carbohydrates (from both grain and non-grain sources) in large amounts is associated with an increased risk of heart disease in overweight and obese women even when fibre intake is high but this requires further confirmation in normal-weight women. Recommendation: Carbohydrate-rich foods should be wholegrain and if they are not, then the lowest GI product available should be consumed. Glycemic index is largely irrelevant for foods that contain small amounts of carbohydrate per serve (such as most vegetables).
Article
Full-text available
This study examined the accuracy and reliability of the MedGraphics VO2000 (VO2000) portable metabolic system and the ParvoMedics TrueOne 2400 (TrueOne 2400) metabolic cart against the criterion Douglas bag (DB) method. Ten healthy males (age 20 ± 1.7 years) had their gas exchange variables measured at rest and during cycling at 50, 100, 150, 200, and 250 W. Each stage was 10–12 min. For half of the stage gas exchange was measured with the DB and TrueOne 2400 simultaneously and for the other half of the stage gas exchange was measured with the VO2000. The testing was performed on two separate days and the order in which the equipment was used in each stage was randomized. Reliability between days for V E (CV 7.3–8.8%) was similar among devices, however, for VO2, and VCO2 the VO2000 (CV 14.2–15.8%) was less reliable compared to the DB (CV 5.3–6.0%) and TrueOne 2400 (CV 4.7–5.7%). The TrueOne 2400 was not significantly different from the DB at rest or any work rate for V E, VO2, or VCO2 (P ≥ 0.05). The VO2000 was significantly different from the DB for V E at 50–100 W, VO2 at rest and 100–250 W, and VCO2 at rest and 200–250 W (all, P < 0.05). The TrueOne 2400 provides accurate and reliable results for the measurement of gas exchange variables. The VO2000 portable metabolic system was less reliable for measuring VO2 and VCO2 and generally overestimates VO2 at most cycling work rates. Further research is needed to confirm the results found with the VO2000.
Article
Full-text available
A Paleolithic diet has been suggested to be more in concordance with human evolutionary legacy than a cereal based diet. This might explain the lower incidence among hunter-gatherers of diseases of affluence such as type 2 diabetes, obesity and cardiovascular disease. The aim of this study was to experimentally study the long-term effect of a Paleolithic diet on risk factors for these diseases in domestic pigs. We examined glucose tolerance, post-challenge insulin response, plasma C-reactive protein and blood pressure after 15 months on Paleolithic diet in comparison with a cereal based swine feed. Upon weaning twenty-four piglets were randomly allocated either to cereal based swine feed (Cereal group) or cereal free Paleolithic diet consisting of vegetables, fruit, meat and a small amount of tubers (Paleolithic group). At 17 months of age an intravenous glucose tolerance test was performed and pancreas specimens were collected for immunohistochemistry. Group comparisons of continuous variables were made by use of the t-test. P < 0.05 was chosen for statistical significance. Simple and multivariate correlations were evaluated by use of linear regression analysis. At the end of the study the Paleolithic group weighed 22% less and had 43% lower subcutaneous fat thickness at mid sternum. No significant difference was seen in fasting glucose between groups. Dynamic insulin sensitivity was significantly higher (p = 0.004) and the insulin response was significantly lower in the Paleolithic group (p = 0.001). The geometric mean of C-reactive protein was 82% lower (p = 0.0007) and intra-arterial diastolic blood pressure was 13% lower in the Paleolithic group (p = 0.007). In evaluations of multivariate correlations, diet emerged as the strongest explanatory variable for the variations in dynamic insulin sensitivity, insulin response, C-reactive protein and diastolic blood pressure when compared to other relevant variables such as weight and subcutaneous fat thickness at mid sternum. There was no obvious immunohistochemical difference in pancreatic islets between the groups, but leukocytes were clearly more frequent in sampled pancreas from the Cereal group. This study in domestic pigs suggests that a Paleolithic diet conferred higher insulin sensitivity, lower C-reactive protein and lower blood pressure when compared to a cereal based diet.
Article
Full-text available
Prevention of cardiovascular diseases by paleolithic or hunter-gatherer diets has been discussed during recent years. Our aim was to assess the effect of a paleolithic diet in a pilot study on healthy volunteers during 3 weeks. The intention was to include 20 subjects, of whom 14 fulfilled the study. Complete dietary assessment was available for six subjects. Mean weight decreased by 2.3 kg (P<0.001), body mass index by 0.8 (P<0.001), waist circumference by 0.5 cm (P=0.001), systolic blood pressure by 3 mm Hg (P=0.03) and plasminogen activator inhibitor-1 by 72% (P=0.020). Regarding nutrient intake, intake of energy decreased by 36%, and other effects were also observed, both favourable (fat composition, antioxidants, potassium-sodium rate) and unfavourable (calcium). This short-term intervention showed some favourable effects by the diet, but further studies, including control group, are needed.
Article
Full-text available
Most studies of diet in glucose intolerance and type 2 diabetes have focused on intakes of fat, carbohydrate, fibre, fruits and vegetables. Instead, we aimed to compare diets that were available during human evolution with more recently introduced ones. Twenty-nine patients with ischaemic heart disease plus either glucose intolerance or type 2 diabetes were randomised to receive (1) a Palaeolithic ('Old Stone Age') diet (n = 14), based on lean meat, fish, fruits, vegetables, root vegetables, eggs and nuts; or (2) a Consensus (Mediterranean-like) diet (n = 15), based on whole grains, low-fat dairy products, vegetables, fruits, fish, oils and margarines. Primary outcome variables were changes in weight, waist circumference and plasma glucose AUC (AUC Glucose(0-120)) and plasma insulin AUC (AUC Insulin(0-120)) in OGTTs. Over 12 weeks, there was a 26% decrease of AUC Glucose(0-120) (p = 0.0001) in the Palaeolithic group and a 7% decrease (p = 0.08) in the Consensus group. The larger (p = 0.001) improvement in the Palaeolithic group was independent (p = 0.0008) of change in waist circumference (-5.6 cm in the Palaeolithic group, -2.9 cm in the Consensus group; p = 0.03). In the study population as a whole, there was no relationship between change in AUC Glucose(0-120) and changes in weight (r = -0.06, p = 0.9) or waist circumference (r = 0.01, p = 1.0). There was a tendency for a larger decrease of AUC Insulin(0-120) in the Palaeolithic group, but because of the strong association between change in AUC Insulin(0-120) and change in waist circumference (r = 0.64, p = 0.0003), this did not remain after multivariate analysis. A Palaeolithic diet may improve glucose tolerance independently of decreased waist circumference.
Article
Background: Because lifestyle-induced improvements in cardiovascular risk factors vary substantially across individuals with type 2 diabetes, we investigated the extent to which increases in fitness explain cardiovascular risk factor improvements independent of weight loss in a lifestyle intervention. Methods: We studied 1-year changes in Look AHEAD, a randomized trial comparing an intensive lifestyle intervention (ILI) to a diabetes support and education (DSE) control group in adults with type 2 diabetes. Assessments included weight, fitness, blood pressure (BP), glucose, HbA1c, and lipids. We evaluated the effects of changes in weight and fitness on changes in cardiovascular risk factors by study arm, using R (2) from multiple linear regression. Results: Analyses included participants with fitness data at baseline and 1-year (n = 4408; 41% male, 36% non-white; mean age 58.7 ± 6.8 years). Weight change alone improved R (2) for explaining changes in risk factors up to 8.2% in ILI and 1.7% in DSE. Fitness change alone improved R (2) up to 3.9% in ILI and 0.8% in DSE. After adjusting for weight change, fitness was independently associated (p < 0.05) with improvements in R (2) for glucose (+0.7%), HbA1c (+1.1%), high-density lipoprotein (HDL) cholesterol (+0.4%), and triglycerides (+0.2%) in ILI and diastolic BP (+0.3%), glucose (+0.3%), HbA1c (+0.4%), and triglycerides (+0.1%) in DSE. Taken together, weight and fitness changes explained from 0.1-9.3% of the variability in cardiovascular risk factor changes. Conclusion: Increased fitness explained statistically significant but small improvements in several cardiovascular risk factors beyond weight loss. Further research identifying other factors that explain cardiovascular risk factor change is needed.
Article
The present study sought to evaluate the relation between cardiovascular risk factors and cardiorespiratory fitness (CRF) in a large population. Low CRF has been associated with increased total mortality and cardiovascular mortality. The mechanisms underlying greater cardiovascular mortality have not yet been determined. A series of cardiovascular risk factors were measured in 59,820 men and 22,192 women who had undergone determinations of CRF with maximal exercise testing. The risk factor profiles were segregated into 5 quintiles of CRF. With decreasing CRF, increases occurred in obesity, triglycerides, non-high-density lipoprotein cholesterol, triglyceride/high-density lipoprotein ratios, blood pressure, metabolic syndrome, diabetes, and cigarette smoking. Self-reported physical activity declined with decreasing levels of CRF. In conclusion, it appears likely that the enrichment of cardiovascular risk factors, especially metabolic risk factors, account for a portion of the increased cardiovascular mortality in low-fitness subjects. The mechanisms responsible for this enrichment in subjects with a low CRF represent a challenge for future research.
Article
Because dairy products provide shortfall nutrients (eg, calcium, potassium, and vitamin D) and other important nutrients, this study hypothesized that it would be difficult for Americans to meet nutritional requirements for these nutrients in the absence of dairy product consumption or when recommended nondairy calcium sources are consumed. To test this hypothesis, MyPyramid dietary pattern modeling exercises and an analyses of data from the National Health and Nutrition Examination Survey 2003-2006 were conducted in those aged at least 2 years (n = 16 822). Impact of adding or removing 1 serving of dairy, removing all dairy, and replacing dairy with nondairy calcium sources was evaluated. Dietary pattern modeling indicated that at least 3 servings of dairy foods are needed to help individuals meet recommendations for nutrients, such as calcium and magnesium, and 4 servings may be needed to help some groups meet potassium recommendations. A calcium-equivalent serving of dairy requires 1.1 servings of fortified soy beverage, 0.6 serving of fortified orange juice, 1.2 servings of bony fish, or 2.2 servings of leafy greens. The replacement of dairy with calcium-equivalent foods alters the overall nutritional profile of the diet and affects nutrients including protein, potassium, magnesium, phosphorus, riboflavin, vitamins A, D and B(12). Similar modeling exercises using consumption data from the National Health and Nutrition Examination Survey also demonstrated that nondairy calcium replacement foods are not a nutritionally equivalent substitute for dairy products. In conclusion, although it is possible to meet calcium intake recommendations without consuming dairy foods, calcium replacement foods are not a nutritionally equivalent substitute for dairy foods and consumption of a calcium-equivalent amount of some nondairy foods is unrealistic.
Article
Overweight and obesity are the foremost public health problems in the U.S., other industrialized countries, and is rapidly increasing in developing countries. Obesity is a multifaceted disease which requires multiple approaches to successfully combat its increase. Nutritional factors play a key role and include modification of energy balance, intake and expenditure, as well as other factors. Emerging scientific evidence over the past decade suggests that dairy foods may be beneficial when included in a moderate energy restricted diet and possibly for weight maintenance as well. This paper provides a review of some of the scientific evidence that has examined the effect of dairy foods and dietary calcium on weight management. Topic areas presented are observational or retrospective studies with adults as well as children and adolescents; randomized clinical trials on body weight and composition, energy expenditure, substrate oxidation and fecal fat loss; research from animal and in vitro studies provide possible mechanisms of action.
Article
Bone health is the resultant of bone mass, bone architecture, and body mechanics. Nutrition supports all three components, with the principal nutrients concerned being calcium, protein, and vitamin D. Potassium, magnesium, zinc, and several vitamins are also involved to varying extents. Given modern food sources, it is difficult to devise a diet that is "bone healthy" without including three servings of dairy per day, not just because of dairy calcium, but dairy protein and potassium as well.
Article
The global burdens of cardiovascular diseases (CVD), type 2 diabetes mellitus (DM), and obesity are rising, producing enormous losses of life and disability-adjusted life-years in both developed and developing nations.1 Most of these burdens are preventable and are occurring at unnecessarily younger ages, largely owing to suboptimal lifestyle, which includes poor diet quality, excess caloric intake, physical inactivity, and smoking.2,–,5 Worldwide, striking differences in dietary habits and rates of chronic diseases exist. The identification and targeting of dietary factors with the greatest potential for reducing CVD, DM, and obesity are of major scientific and public health importance. The science of diet and chronic disease is relatively young, spanning perhaps only half a century.6 New advances offer substantial evidence from complementary research paradigms on cardiometabolic effects of specific dietary factors. Several recent evidence-based reviews conducted in conjunction with national and international policy-making efforts provide the context for the present report. The need to prioritize selected foods and overall dietary patterns rather than only individual nutrients, the relevance of carbohydrate and fat quality as well as quantity, the effects and policy implications of sodium consumption, the importance of energy balance, and the role of dietary supplements represent several key findings of interest. Evidence-based insights into successful individual and public health strategies for behavior change are also addressed. Overall, the present report is intended to provide a useful framework for health practitioners and policy makers to understand contemporary issues related to the effects of diet on CVD. Evidence for effects of dietary factors on cardiometabolic health was reviewed, often derived from recent comprehensive reviews performed for policy-making or similar activities, including those of the American Heart Association (AHA) 2020 Impact Goals Committee (D.M., L.J.A.),7 the AHA Nutrition Committee (D.M., L.J.A., L.V.H.),8,9 the …
Article
A whole grain consists of the intact, ground, cracked, or flaked caryopsis, whose principal anatomical components--the starchy endosperm, germ, and bran--are present in the same relative proportions as they exist in the intact caryopsis. Whole grain food products can be intact, consisting of the original composition of bran, germ, and endosperm, throughout the entire lifetime of the product, or reconstituted, in which one or more of the original components of a whole grain is recombined to the relative proportion naturally occurring in the grain kernel. Increased consumption of whole grains has been associated with reduced risk of major chronic diseases including cardiovascular disease, type II diabetes, and some cancers. Whole grain foods offer a wide range of phytochemicals with health benefits that are only recently becoming recognized. The unique phytochemicals in whole grains are proposed to be responsible for the health benefits of whole grain consumption. In this paper, whole grain phytochemicals and the health benefits associated with their consumption are reviewed.
Article
The role of starchy plants in early hominin diets and when the culinary processing of starches began have been difficult to track archaeologically. Seed collecting is conventionally perceived to have been an irrelevant activity among the Pleistocene foragers of southern Africa, on the grounds of both technological difficulty in the processing of grains and the belief that roots, fruits, and nuts, not cereals, were the basis for subsistence for the past 100,000 years and further back in time. A large assemblage of starch granules has been retrieved from the surfaces of Middle Stone Age stone tools from Mozambique, showing that early Homo sapiens relied on grass seeds starting at least 105,000 years ago, including those of sorghum grasses.
Article
Studies designed to examine effects of weight reduction by dieting on total cholesterol (TC), low-density-lipoprotein cholesterol (LDL-C), high-density-lipoprotein cholesterol (HDL-C), very-low-density-lipoprotein cholesterol (VLDL-C), and triglycerides (TGs) have reported inconsistent results. The purpose of this study was to quantify effects of weight loss by dieting on lipids and lipoproteins through the review method of meta-analysis. Results from the 70 studies analyzed indicated that weight reduction was associated with significant decreases (P less than or equal to 0.001) and correlations (P less than or equal to 0.05) for TC (r = 0.32), LDL-C (r = 0.29), VLDL-C (r = 0.38), and TG (r = 0.32). For every kilogram decrease in body weight, a 0.009-mmol/L increase (P less than or equal to 0.01) in HDL-C occurred for subjects at a stabilized, reduced weight and a 0.007-mmol/L decrease (P less than or equal to 0.05) for subjects actively losing weight. Our results indicate that weight reduction through dieting can be a viable approach to help normalize plasma lipids and lipoproteins in overweight individuals.
Article
From a genetic standpoint, humans living today are Stone Age hunter-gatherers displaced through time to a world that differs from that for which our genetic constitution was selected. Unlike evolutionary maladaptation, our current discordance has little effect on reproductive success; rather it acts as a potent promoter of chronic illnesses: atherosclerosis, essential hypertension, many cancers, diabetes mellitus, and obesity among others. These diseases are the results of interaction between genetically controlled biochemical processes and a myriad of biocultural influences--lifestyle factors--that include nutrition, exercise, and exposure to noxious substances. Although our genes have hardly changed, our culture has been transformed almost beyond recognition during the past 10,000 years, especially since the Industrial Revolution. There is increasing evidence that the resulting mismatch fosters "diseases of civilization" that together cause 75 percent of all deaths in Western nations, but that are rare among persons whose lifeways reflect those of our preagricultural ancestors.
Article
A method for estimating the cholesterol content of the serum low-density lipoprotein fraction (Sf- 0.20)is presented. The method involves measure- ments of fasting plasma total cholesterol, tri- glyceride, and high-density lipoprotein cholesterol concentrations, none of which requires the use of the preparative ultracentrifuge. Cornparison of this suggested procedure with the more direct procedure, in which the ultracentrifuge is used, yielded correlation coefficients of .94 to .99, de- pending on the patient population compared. Additional Keyph rases hyperlipoproteinemia classifi- cation #{149} determination of plasma total cholesterol, tri- glyceride, high-density lipoprotein cholesterol #{149} beta lipo proteins
Article
A new device based on the plethysmographic measurement of body volume has been developed for the purpose of estimating human body composition. The device, the BOD POD Body Composition System, uses the relationship between pressure and volume to derive the body volume of a subject seated inside a fiberglass chamber. Derivation of body volume, together with measurement of body mass, permits calculation of body density and subsequent estimation of percent fat and fat-free mass. Critical issues which have hampered prior plethysmographic approaches are discussed. The present system's ability to measure the volume of inanimate objects was evaluated for accuracy, reliability, and linearity. Twenty successive tests of a known volume (50,039 ml) on two separate days produced values of 50,037 +/- 12.7 ml and 50,030 +/- 13.5 ml (mean +/- SD) for each day, respectively. The CV for these series were 0.025% and 0.027%. Further testing across a wide range of volumes approximating human size (25-150 1) produced the following regression equation where y = measured volume (1) and x = actual volume (1): y = 0.9998x - 0.0274, r2 = 1.0, SEE = 0.004 1. The resultant device is likely to enhance opportunities for the quick, simple and noninvasive measurement of body composition for both research and clinical applications.
Article
Over the past decade, considerable attention has been paid to accurately measuring body composition in diverse populations. Recently, the use of air-displacement plethysmography (AP) was proposed as an accurate, comfortable, and accessible method of body-composition analysis. The purpose of this study was to compare measurements of percentage body fat (%BF) by AP and 2 other established techniques, hydrostatic weighing (HW) and bioelectrical impedance analysis (BIA), in adults. The sample consisted of healthy men (n = 23) and women (n = 24). %BF was measured by AP, HW, and BIA. In the total group, %BF(AP) (25.0+/-8.9%) was not significantly different from %BF(HW) (25.1+/-7.7%) or %BF(BIA) (23.9+/-7.7%), and %BF(AP) was significantly correlated with %BF(HW) (r = 0.944, P < 0.001) and with %BF(BIA) (r = 0.859, P < 0.01). Compared with HW, AP underestimated %BF in men (by -1.24+/-3.12%) but overestimated %BF in women (by 1.02+/-2.48%), indicating a significant sex effect (P < 0.05). The differences in estimation between AP and BIA and between BIA and HW were not significantly different between the sexes. AP is an accurate method for assessing body composition in healthy adults. Future studies should assess further the cause of the individual variations with this new method.
Article
Dietary guidelines recommend the consumption of whole grains to prevent chronic diseases. Epidemiologic studies support the theory that whole grains are protective against cancer, especially gastrointestinal cancers such as gastric and colon can-cer, and cardiovascular disease. Components in whole grains that may be protective include compounds that affect the gut environment, such as dietary fiber, resistant starch, and oligosaccharides. Whole grains are also rich in compounds that function as antioxidants, such as trace minerals and phenolic compounds, and phytoestrogens, with potential hormonal effects. Other potential mechanisms whereby whole grains may protect against disease include binding of carcinogens and modulation of the glycemic response. Clearly, the range of protective substances in whole grains is impressive and advice to consume additional whole grains is justified. Further study is needed regarding the mechanisms behind this protection so that the most potent protective components of whole grains will be maintained when developing whole grains into acceptable food products for the public.
Article
The effects of a walking training programme were assesed on 10 healthy, active men aged 63-69 years. Serum lipids, pulse and blood pressure, maximum oxygen consumption (VO2 max) and anthropometric parameters, were measured before and after this programme. There was a significant fall in LDL (p<0.02) and mean diastolic BP (p<0.005). In spite of the subjects's initial good level of fitness there was still an 8% rise in the mean VO2 max of the group. There was also a significant loss of body fat (P<0.01). These positive physiological effects suggest that brisk walking can be considered as a a useful activity for improving the fitness and general health in this age-range.
Article
Maximal oxygen uptake (.VO2max) was defined by Hill and Lupton in 1923 as the oxygen uptake attained during maximal exercise intensity that could not be increased despite further increases in exercise workload, thereby defining the limits of the cardiorespiratory system. This concept has recently been disputed because of the lack of published data reporting an unequivocal plateau in .VO2 during incremental exercise. The purpose of this investigation was to test the hypothesis that there is no significant difference between the .VO2max obtained during incremental exercise and a subsequent supramaximal exercise test in competitive middle-distance runners. We sought to determine conclusively whether .VO2 attains a maximal value that subsequently plateaus or decreases with further increases in exercise intensity. Fifty-two subjects (36 men, 16 women) performed three series of incremental exercise tests while measuring .VO2 using the Douglas bag method. On the day after each incremental test, the subjects returned for a supramaximal test, during which they ran at 8% grade with the speed chosen individually to exhaust the subject between 2 and 4 min. .VO2 at supramaximal exercise intensities (30% above incremental .VO2max) was measured continuously. .VO2max measured during the incremental test (63.3 +/- 6.3 mL.kg(-1).min(-1); mean +/- SD) was indistinguishable from the .VO2max during the supramaximal test (62.9 +/- 6.2, N = 156; P = 0.77) despite a sufficient duration of exercise to demonstrate a plateau in .VO2 during continuous supramaximal exercise. These data provide strong support for the hypothesis that there is indeed a peak and subsequent plateau in .VO2 during maximal exercise intensity. .VO2max is a valid index measuring the limits of the cardiorespiratory systems' ability to transport oxygen from the air to the tissues at a given level of physical conditioning and oxygen availability.
A new air displacement method for the determination of human body composition Paleolithic nutrition. A consideration of its nature and current implications
  • P Dempster
  • S Aitkens
  • Sb Eaton
  • M Konner
Dempster P, Aitkens S. A new air displacement method for the determination of human body composition. Medicine and Science in Sports and Exercise 27(12):1692-7, 1995. 10. Eaton SB, Konner M. Paleolithic nutrition. A consideration of its nature and current implications. N Engl J Med 312(5):283-9, 1985.
Accuracy and precision of the Cholestech LDX System in monitoring blood lipid levels Effects of aerobic training on serum omentin-1 and cardiometabolic risk factors in overweight and obese men
  • J Santee
  • M Asghari
  • A Ghorbani
Santee J. Accuracy and precision of the Cholestech LDX System in monitoring blood lipid levels. Am J Health Syst Pharm 59(18):1774-9, 2002. 42. Saremi A, Asghari M, Ghorbani A. Effects of aerobic training on serum omentin-1 and cardiometabolic risk factors in overweight and obese men. J Sports Sci 28(9):993-8, 2010.
  • American Heart Association Nutrition
  • C Lichtenstein
  • Ah Appel
  • Lj Brands
  • M Carnethon
  • M Daniels
  • S Franch
  • Ha Franklin
  • B Kris-Etherton
  • P Harris
  • Ws Howard
  • B Karanja
  • N Lefevre
  • M Rudel
  • L Sacks
  • F Van Horn
  • L Winston
  • M Wylie-Rosett
American Heart Association Nutrition C, Lichtenstein AH, Appel LJ, Brands M, Carnethon M, Daniels S, Franch HA, Franklin B, Kris-Etherton P, Harris WS, Howard B, Karanja N, Lefevre M, Rudel L, Sacks F, Van Horn L, Winston M, Wylie-Rosett J. Diet and lifestyle recommendations revision 2006: a scientific statement from the American Heart Association Nutrition Committee. Circulation 114(1):82-96, 2006.