ArticleLiterature Review

Effects of Medium-Chain Triglycerides on Weight Loss and Body Composition: A Meta-Analysis of Randomized Controlled Trials

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Abstract

Medium-chain triglycerides (MCTs) may result in negative energy balance and weight loss through increased energy expenditure and lipid oxidation. However, results from human intervention studies investigating the weight reducing potential of MCTs, have been mixed. To conduct a systematic review and meta-analysis of randomized controlled trials comparing the effects of MCTs, specifically C8:0 and C10:0, to long-chain triglycerides (LCTs) on weight loss and body composition in adults. Changes in blood lipid levels were secondary outcomes. Randomized controlled trials >3 weeks' duration conducted in healthy adults were identified searching Web of Knowledge, Discover, PubMed, Scopus, New Zealand Science, and Cochrane CENTRAL until March 2014 with no language restriction. Identified trials were assessed for bias. Mean differences were pooled and analyzed using inverse variance models with fixed effects. Heterogeneity between studies was calculated using I(2) statistic. An I(2)>50% or P<0.10 indicated heterogeneity. Thirteen trials (n=749) were identified. Compared with LCTs, MCTs decreased body weight (-0.51 kg [95% CI-0.80 to -0.23 kg]; P<0.001; I(2)=35%); waist circumference (-1.46 cm [95% CI -2.04 to -0.87 cm]; P<0.001; I(2)=0%), hip circumference (-0.79 cm [95% CI -1.27 to -0.30 cm]; P=0.002; I(2)=0%), total body fat (standard mean difference -0.39 [95% CI -0.57 to -0.22]; P<0.001; I(2)=0%), total subcutaneous fat (standard mean difference -0.46 [95% CI -0.64 to -0.27]; P<0.001; I(2)=20%), and visceral fat (standard mean difference -0.55 [95% CI -0.75 to -0.34]; P<0.001; I(2)=0%). No differences were seen in blood lipid levels. Many trials lacked sufficient information for a complete quality assessment, and commercial bias was detected. Although heterogeneity was absent, study designs varied with regard to duration, dose, and control of energy intake. Replacement of LCTs with MCTs in the diet could potentially induce modest reductions in body weight and composition without adversely affecting lipid profiles. However, further research is required by independent research groups using large, well-designed studies to confirm the efficacy of MCT and to determine the dosage needed for the management of a healthy body weight and composition. Copyright © 2015 Academy of Nutrition and Dietetics. Published by Elsevier Inc. All rights reserved.

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... Over a faster metabolism and less deposition in adipocytes, MCTs can significantly influence energy balance, favouring body weight loss independently of dietary energy intake [25,26]. ...
... Our results are in line with previous studies focusing on supplementation with MCTs during energy-restricted diets [25,26]. Indeed, two meta-analyses [25,26] showed that the isoenergetic substitution of LCTs with MCTs during energy-restricted dietary interventions resulted in a small reduction in body weight (− 0.5 to − 0.7 kg) and waist circumference (− 1.5 to − 1.8 cm) in middleaged individuals with overweight/obesity. ...
... Our results are in line with previous studies focusing on supplementation with MCTs during energy-restricted diets [25,26]. Indeed, two meta-analyses [25,26] showed that the isoenergetic substitution of LCTs with MCTs during energy-restricted dietary interventions resulted in a small reduction in body weight (− 0.5 to − 0.7 kg) and waist circumference (− 1.5 to − 1.8 cm) in middleaged individuals with overweight/obesity. However, when considering studies involving very low-calorie diets (< 800 kcal/day) with MCTs supplementation the mean weight reduction was similar to that observed in our study (on average − 8 kg). ...
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Background Very low-calorie ketogenic diet (VLCKD) has shown to significantly reduce body weight and fat mass, as well as inflammation. These effects are supported by nutritional ketosis, which triggers the utilization of the ketone body as an energy source. Medium-chain fatty acids (MCTs) might serve as potential enhancers of ketone bodies production with a greater effect on weight loss. Nevertheless, no clinical studies have evaluated the effect of MCTs supplementation in addition to VLCKD. Therefore, the present study aimed to evaluate whether the supplementation with MCTs can induce a greater weight reduction during the ketogenic phase of VLCKD. Methods In this retrospective study, 263 women with overweight/obesity (body mass index, BMI: 35.7 ± 5.3 kg/m ² ) aged 37.5 ± 14.2 years followed one of these dietary protocols for 45 days: (a) Control group, 83 participants (31.6%) (VLCKD without MCTs), (b) VLCKD + MCTs group, 86 participants (32.7%) (MCTs supplementation − 20 g/day- during VLCKD starting from the first day of the active phase), (c) VLCKD + earlyMCTs, 94 participants (35.7%) (MCTs supplementation − 20 g/day-starting from 5 days before the beginning of the VLCKD active phase. Anthropometric measures, body composition, and c-reactive protein (CRP) concentrations were collected at the beginning and at the end (45 days) of the VLCKD intervention. Results MCTs supplementation significantly decreased body weight, BMI, and waist circumference as compared to the control group, with a greater effect in the VLCKD + earlyMCTs group. A two-fold decrease in fat mass and an increase in muscle mass were observed in the VLCKD + earlyMCTs group as compared to the control group. As for inflammation, hs-CRP concentrations (assessed as absolute percent change) were significantly lower in the VLCKD + MCTs group ( p = 0.009) and the VLCKD + earlyMCTs group ( p = 0.011) than in the control group. A logistic regression model showed that VLCKD + earlyMCTs increase the likelihood of improvement of BMI classes (OR: 1.85, 95% CI 1.02–3.36) also after adjusting for the potential confounding factors. Conclusion MCTs supplementation (20 g/day) may be a useful tool to enhance the beneficial effect of VLCKD on the reduction of body weight and fat mass. In particular, MCTs supplementation before the beginning of the VLCKD active phase might facilitate ketosis thus contributing to the effectiveness of the nutritional intervention.
... Several studies have been conducted. Mumme et al. conducted a meta-analysis using 13 human studies and reported that replacing a portion of ingested LCTs with MCTs reduced body fat and weight (124). Fukazawa et al. reported that high-fat diets based on MCTs enhanced lipid metabolism without increasing PDK-4 expression in skeletal muscle in animal experiments, indicating that it may be possible to enhance lipid metabolism without suppressing the glycolytic system (125). ...
... Many clinical studies have been conducted on the prevention of obesity by ingestion of MCTs. Since 2010 there have been several clinical research articles published on the effects of ingestion of MCTs on body composition, weight loss, and energy expenditure (124,(154)(155)(156)(157). Among them are two SRs (124,158). ...
... Since 2010 there have been several clinical research articles published on the effects of ingestion of MCTs on body composition, weight loss, and energy expenditure (124,(154)(155)(156)(157). Among them are two SRs (124,158). The review by Mumme et al. selected and analyzed randomized clinical studies with a duration of ingestion of at least 3 weeks, comparing MCTs (consisting of C8:0 and C10:0) with LCTs for body composition, weight, serum lipids, and other endpoints in healthy men and women (124). ...
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In the 1950s, the production of processed fats and oils from coconut oil was popular in the United States. It became necessary to find uses for the medium-chain fatty acids (MCFAs) that were byproducts of the process, and a production method for medium-chain triglycerides (MCTs) was established. At the time of this development, its use as a non-fattening fat was being studied. In the early days MCFAs included fatty acids ranging from hexanoic acid (C6:0) to dodecanoic acid (C12:0), but today their compositions vary among manufacturers and there seems to be no clear definition. MCFAs are more polar than long-chain fatty acids (LCFAs) because of their shorter chain length, and their hydrolysis and absorption properties differ greatly. These differences in physical properties have led, since the 1960s, to the use of MCTs to improve various lipid absorption disorders and malnutrition. More than half a century has passed since MCTs were first used in the medical field. It has been reported that they not only have properties as an energy source, but also have various physiological effects, such as effects on fat and protein metabolism. The enhancement of fat oxidation through ingestion of MCTs has led to interest in the study of body fat reduction and improvement of endurance during exercise. Recently, MCTs have also been shown to promote protein anabolism and inhibit catabolism, and applied research has been conducted into the prevention of frailty in the elderly. In addition, a relatively large ingestion of MCTs can be partially converted into ketone bodies, which can be used as a component of “ketone diets” in the dietary treatment of patients with intractable epilepsy, or in the nutritional support of terminally ill cancer patients. The possibility of improving cognitive function in dementia patients and mild cognitive impairment is also being studied. Obesity due to over-nutrition and lack of exercise, and frailty due to under-nutrition and aging, are major health issues in today's society. MCTs have been studied in relation to these concerns. In this paper we will introduce the results of applied research into the use of MCTs by healthy subjects.
... Individual SFAs vary widely in their physiological effects on health; therefore, it is important to consider the specific dietary source of SFAs consumed [3,5]. For example, many studies using humans and animals have reported that consumption of medium chain triglycerides (MCTs) has resulted in reductions in body weight and adiposity and may even confer beneficial effects on cardiovascular disease risk [6,7]. ...
... triglycerides (LCTs) with sources of medium chain triglycerides (MCTs) is associated with significant weight loss [3,6,23,24]. Consistent with these findings, mean body mass in male and female zebrafish fed the HFC2 diet was significantly lower than mean body mass of fish fed the HFP2 diet. ...
... A large body of evidence has demonstrated that consumption of MCTs significantly reduces adiposity in both humans and rodents [6,30]. In contrast to these studies, we found that inclusion of coconut oil had no effect on adiposity in zebrafish relative to other sources of saturated fat; instead, adiposity increased along with total intake of dietary fat. ...
Article
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The effects of saturated fat intake on obesity and cardiovascular health remain inconclusive, likely due in part to their varied nature and interactions with other nutrients. Investigating the synergistic effects of different saturated fat sources with other dietary lipid components will help establish more accurate nutritional guidelines for dietary fat intake. Over the past two decades, zebrafish (Danio rerio) have been established as an attractive model system to address questions regarding contributions of dietary lipid intake to diet-induced obesity in humans. The goal of the present study was to assess interactions of three different saturated fat sources (milk fat, palm oil, and coconut oil) with sex and total dietary lipid intake on weight gain and body composition in adult zebrafish. Larvae were raised on live feeds until 28 days post fertilization, and then fed a formulated maintenance diet until three months of age. An eight-week feeding trial was then initiated, in which zebrafish were fed nine experimental low-and high-fat diets varying in saturated fatty acid and long-chain polyunsaturated fatty acid content, in addition to a low-fat and high-fat control diet. At termination of the feeding trial, each treatment was evaluated according to body mass, moisture content, and adi-posity. Sex and diet significantly interacted in their effects on body mass (P = 0.026), moisture content (P = 0.044), and adiposity (P = 0.035). The influence of saturated fat source on body mass was observed to be dependent on intake of total dietary lipid. In females, all three saturated fat sources had similar effects on adiposity. From these observations , we hypothesize that impacts of saturated fat intake on energy allocation and obesity related phenotypes are influenced by both sex and intake of other dietary lipid components. Our results suggest that current nutritional guidelines for saturated fat intake may need to be re-evaluated and take sex-specific recommendations into consideration.
... However, not all the saturated fatty acids have been reported to be metabolically detrimental. Indeed, medium-chain saturated fatty acids, such as lauric acid (LA), have been shown not to promote insulin resistance, to be less obesogenic, and to decrease the ratio of total cholesterol to high-density lipoprotein cholesterol compared to longer chain saturated fatty acids (29)(30)(31)(32). LA has been reported to be less metabolically detrimental and proinflammatory compared to PA (33). ...
... The results of this study highlight the contrasting effects of PA and LA on metabolic inflammation, mitochondrial dynamics, and function in human primary myotubes, providing mechanistic insights on the effects of long-vs. medium-chain saturated fatty acids on metabolic health (31,32) and particularly on insulin sensitivity (29,50). ...
... Independently on whether mitochondrial fragmentation and the drop in mitochondrial membrane potential are a consequence or a cause of metabolic inflammation, these are both pathophysiological mechanisms associated with skeletal muscle insulin resistance, which, however, was not directly assessed in the experimental model used as part of this study. Therefore, the ability of PA to trigger these mechanisms, as opposed to LA, further supports the contrasting effects of these fatty acids on metabolic health, previously reported (29)(30)(31)(32)(33). Thus, despite PA and LA being both saturated fatty acids, their chain lengths, C12:0 vs. C16:0, respectively, appear to be an important discriminant in dictating the effects of these fatty acids on mitochondrial health as well as inflammation. ...
Article
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The chain length of saturated fatty acids may dictate their impact on inflammation and mitochondrial dysfunction, two pivotal players in the pathogenesis of insulin resistance. However, these paradigms have only been investigated in animal models and cell lines so far. Thus, the aim of this study was to compare the effect of palmitic (PA) (16:0) and lauric (LA) (12:0) acid on human primary myotubes mitochondrial health and metabolic inflammation. Human primary myotubes were challenged with either PA or LA (500 μM). After 24 h, the expression of interleukin 6 (IL-6) was assessed by quantitative polymerase chain reaction (PCR), whereas Western blot was used to quantify the abundance of the inhibitor of nuclear factor κB (IκBα), electron transport chain complex proteins and mitofusin-2 (MFN-2). Mitochondrial membrane potential and dynamics were evaluated using tetraethylbenzimidazolylcarbocyanine iodide (JC-1) and immunocytochemistry, respectively. PA, contrarily to LA, triggered an inflammatory response marked by the upregulation of IL-6 mRNA (11-fold; P < 0.01) and a decrease in IκBα (32%; P < 0.05). Furthermore, whereas PA and LA did not differently modulate the levels of mitochondrial electron transport chain complex proteins, PA induced mitochondrial fragmentation (37%; P < 0.001), decreased MFN-2 (38%; P < 0.05), and caused a drop in mitochondrial membrane potential (11%; P < 0.01) compared to control, with this effect being absent in LA-treated cells. Thus, LA, as opposed to PA, did not trigger pathogenetic mechanisms proposed to be linked with insulin resistance and therefore represents a healthier saturated fatty acid choice to potentially preserve skeletal muscle metabolic health.
... In addition, some people use MCTs to increase satiety and curb appetite to lose weight or avoid gain of body weight. 47,74 After hydrolysis of MCTs in the gastrointestinal tract by lipase, the free MCFAs can diffuse directly into portal vein and then mostly to mitochondria of liver, but also extrahepatic tissues. 47 In the brain, MCFAs are mostly metabolized by astrocytes (see below). ...
... 116 Similarly, there was less stranger-directed fear in dogs fed a 5.5E% MCT diet. 100 Finally, several studies have indicated that MCTs may also be beneficial for metabolic syndrome, diabetes, and obesity. 74,146 7 | CONCLUSION AND FUTURE DIRECTIONS Some epilepsies show perturbed utilization of glucose and energy production in epileptogenic brain areas. As most energy in the brain is needed to maintain ion balances and regulate glutamate transport and metabolism, it is likely that energy deficiencies can contribute to hyperexcitability and seizures. ...
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Many studies show that glucose metabolism in epileptic brain areas can be impaired. Energy is crucial to maintain normal brain function, including ion and neurotransmitter balances. Energy deficits can lead to disruption of ion gradients, which can trigger neuronal depolarization and generation of seizures. Thus, perturbed metabolic processing of glucose in epileptogenic brain areas indicates a specific nutritional need for people and animals with epilepsy, as they are likely to benefit from auxiliary brain fuels other than glucose. Ketogenic diets provide the ketone bodies acetoacetate and β‐hydroxybutyrate, which can be used as auxiliary fuel by the brain. In approximately 50% children and adults with certain types of epilepsy, who can tolerate and maintain these dietary regimens, seizure frequency can be effectively reduced. More recent data demonstrate that addition of medium chain triglycerides (MCTs), which provide the medium chain fatty acids octanoic and decanoic acid, as well as ketone bodies as auxiliary brain energy, can be beneficial in rodent seizure models, and dogs and humans with epilepsy. Here, this evidence is reviewed, including tolerance in 65% of humans, efficacy studies in dogs, possible anticonvulsant mechanisms of actions of MCTs, and specifically decanoic acid as well as metabolic and antioxidant mechanisms. In conclusion, MCTs are a promising adjunct to standard pharmacological treatment for both humans and dogs with epilepsy, as they lack central nervous system side effects found with current antiepileptic drugs. There is now a need for larger clinical trials in children, adults, and dogs to find the ideal composition and doses of MCTs and the types of epilepsy that respond best.
... Pada penelitian ini, terdapat penurunan berat badan pada sampel walaupun tidak secara signifikan (Tabel 3). Hal ini sesuai dengan penelitian lain yang membandingkan efek penggantian trigliserida rantai panjang (LCT) dengan MCT terhadap penurunan berat badan dan perubahan kadar lipid darah pada orang dewasa (Mumme & Stonehouse, 2015). Diketahui bahwa penggunaan lemak rantai sedang (MCT) dalam makanan berpotensi menyebabkan penurunan berat badan, tanpa mempengaruhi profil lipid. ...
Article
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Obesitas pada anak dapat berlanjut sampai dewasa disertai risiko penyakit penyerta seperti jantung koroner, stroke, penyakit kantung empedu, diabetes, hipertensi, hiperlipidemia, dan berbagai penyakit lainnya yang dapat menurunkan usia harapan hidup. Edukasi atau pendampingan gizi melalui konseling merupakan salah satu upaya mencegah masalah gizi dan kesehatan, karena dapat meningkatkan pengetahuan dan perubahan perilaku untuk mencapai status gizi dan kesehatan yang optimal. Terdapat berbagai faktor penyebab kegemukan, antara lain asupan makanan berlebih, kurangnya aktivitas fisik, faktor genetik, hormonal, dan lingkungan. Minyak kelapa murni (VCO) mengandung 70-85% asam lemak rantai sedang (MCFAs) yang mudah teroksidasi dan tidak disimpan dalam jaringan lemak tubuh (adiposa), memberi rasa kenyang, serta membantu mengurangi selera makan. Dengan berkurangnya selera makan, maka asupan kalori dari makanan juga dapat berkurang, sehingga memungkinkan terjadinya penurunan berat badan. Tujuan penelitian ini yaitu mengetahui pengaruh konseling menggunakan buku saku dan pemberian VCO terhadap pengetahuan gizi, asupan zat gizi dan status gizi siswa SD obesitas di Madrasah Ibtidaiyah (MI) Ummushabri Pesri Kendari, pada Maret-Agustus 2018. Tipe penelitian ini adalah eksperimental semu dengan desain pra tes dan pasca tes. Populasi pada penelitian ini adalah semua siswa SD obesitas kelas 4, 5, dan 6 berumur 10-12 tahun. Sampel sebanyak 30 orang, diambil secara purposive sampling. Analisis data dilakukan menggunakan uji T berpasangan. Hasil penelitian menunjukkan bahwa terdapat perbedaan bermakna pada pengetahuan gizi, asupan energi, protein, dan karbohidrat pada subyek penelitian setelah dilakukan konseling gizi menggunakan buku saku “Gentas” dan pemberian VCO. Sedangkan pada asupan lemak, serat dan status gizi tidak terdapat perbedaan bermakna setelah pemberian intervensi.
... We found an inverse, though non-significant, relation between MCFAs in human milk and infant growth. As noted above, compared to LC-PUFAs, MCFAs are more readily oxidized for energy rather than being stored in adipose tissue for later use, resulting in less weight gain [61,63]. In animal models, breastfeeding pups of mice fed high-MCFA diets of virgin coconut oil showed significantly lower body weight [64]. ...
Article
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Triglyceride-bound fatty acids constitute the majority of lipids in human milk and may affect infant growth. We describe the composition of fatty acids in human milk, identify predictors, and investigate associations between fatty acids and infant growth using data from the Norwegian Human Milk Study birth cohort. In a subset of participants (n = 789, 30% of cohort), oversampled for overweight and obesity, we analyzed milk concentrations of detectable fatty acids. We modelled percent composition of fatty acids in relation to maternal body mass index, pregnancy weight gain, parity, smoking, delivery mode, gestational age, fish intake, and cod liver oil intake. We assessed the relation between fatty acids and infant growth from 0 to 6 months. Of the factors tested, excess pregnancy weight gain was positively associated with monounsaturated fatty acids and inversely associated with stearic acid. Multiparity was negatively associated with monounsaturated fatty acids and n-3 fatty acids while positively associated with stearic acid. Gestational age was inversely associated with myristic acid. Medium-chain saturated fatty acids were inversely associated with infant growth, and mono-unsaturated fatty acids, particularly oleic acid, were associated with an increased odds of rapid growth. Notably, excessive maternal weight gain was associated with cis-vaccenic acid, which was further associated with a threefold increased risk of rapid infant growth (OR = 2.9, 95% CI 1.2–6.6), suggesting that monounsaturated fatty acids in milk may play a role in the intergenerational transmission of obesity.
... fer of lipids to the liver, rather than extrahepatic tissues, may be associated with reduced fat deposition and might reduce the incidence of obesity. MCTs have been extensively investigated for reducing body fat accumulation in rats and humans 9,11,12 . However, the anti-obesity effect of MCTs was found to be dependent on the nutritional conditions, given that a part of MCTs might promote hepatic lipogenesis 13,14 . ...
Article
d-Allulose (d-psicose) is a rare sugar, that contains no calories and exhibits 70% relative sweetness when compared with sucrose. Recently, several studies have demonstrated the anti-obesity effect of d-allulose, mediated by suppressing lipogenesis and increasing energy expenditure. Medium-chain triacylglycerols (MCTs) are lipids formed by 3 medium-chain fatty acids (MCFAs) with 6–12 carbon atoms attached to glycerol. MCTs have been expensively studied to reduce body fat accumulation in rats and humans. The anti-obesity effect of MCTs was not confirmed depending on the nutritional conditions because MCT might promote lipogenesis. In the present study, we examined the effects of simultaneous intake of diets containing low (5%) or high (13%) MCTs, with or without 5% d-allulose, on body fat accumulation in rats (Experiment 1). Furthermore, we assessed the interaction between 5% MCT and 5% d-allulose in the diet (Experiment 2). In Experiment 1, intra-abdominal adipose tissue weight was significantly greater in the high MCT diet groups than in the commercial diet (control) group. d-Allulose significantly decreased weights of intra-abdominal adipose tissue, carcass fat, and total body fat, however, these weights increased as the amount of MCT added increased. In Experiment 2, d-allulose significantly decreased almost all body fat indicators, and these values were not influenced by the presence or absence of MCT addition. The antiobesity effect of d-allulose was observed with or without dietary MCT, and no synergistic effect was detected between d-allulose and MCT. These results suggest that d-allulose is a beneficial food ingredient in diets aimed at reducing body fat accumulation. However, further research is required on the synergistic effects between d-allulose and MCTs. graphical abstract Fullsize Image
... Substitution of LCTs with MCTs in the diet could possibly induce modest reduction in body weight. [82] The short and long-chain acyl triglyceride molecule (Salatrim) is recognized nowadays as a novel food additive categorized as a reduced-calorie fat substitute. Salatrim can be formed by the inter-esterification of tripropionin, triacetin, tributyrin and hydrogenated vegetable oils. ...
Article
Fat replacers are added to food to provide some or all of the functional properties of natural fat while providing fewer calories. The majority of fat-based replacers are either low-calorie fats that include chemically altered triglycerides or fat substitutes (i.e., lipid analogs that are neither hydrolyzed nor absorbed by the body as natural fat). This review capitalizes on fat substitutes of different origins in the context of their different chemical synthesis, lowering calorie mechanisms, nutritional benefits, metabolism, and safety reports of these substitutes in humans are dissected for the first time in relation to their metabolic byproducts inside humans. Besides, their functional properties and recent advances in pharma-food applications are reviewed. Fat substitutes offer a trendy replacer with less health risks compared to conventional fats. Their different structural chemical classes exert their low-calorie actions under different action mechanisms like emulsifica-tion or modification as structured lipids. Regarding their metabolism, they can retard the absorption of some nutrients acting as anti-nutrients, while their biotransformation products inside the colon might affect microbiota activity or predominance. Fat substitutes offer multiple functions in food processing, using them as preservatives and developing therapeutic tailor-made fat substitutes are the futuristic directions without their current side effects, especially if consumed regularly.
... Higher intake of PUFA-3 and MUFA suppress the expression of lipogenesis genes in various organs and increase fatty acid β-oxidation [53]. Therefore, unsaturated fatty acids can play an important role in the weight loss and body composition [54]. In general, omega-3 fatty acids and MUFA have the anti-inflammatory effect, anti-arrhythmic effect, and anti-thrombotic effect, while omega-6 fatty acids tend to cause inflammation and thrombus formation [55]. ...
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Background The association between anthropometric measures and dietary fat quality indices is unclear in pediatric age groups. The present study aimed to assess the association between dietary lipophilic index (LI) and thrombogenic index (TI) as dietary fat quality indices with anthropometric measurements in children and adolescents. Method This nationwide cross-sectional study was conducted on 4323 students aged 6-18 years that were selected by multistage cluster sampling from 31 provinces of Iran. Dietary intake was collected using a validated food frequency questionnaire and dietary LI and TI were calculated by formula. Data on anthropometric measures were collected by standard protocols. Results The multivariate regression analysis revealed that TI and LI had inverse association with neck circumference Z-score (β = 0.11, p = 0.013 and β = 0.12 p = 0.006, respectively). There was a positive correlation between LI with height Z-score (β = 0.12, 95% CI: 0.01, p = 0.009). However, there was no significant association between LI and TI with other anthropometric indices ( P > 0.05). Conclusion The quality of dietary fats was associated with some anthropometric indices. Further large-scale studies are required to highlight the importance of dietary fat quality indices in relation to cardio-metabolic risk factors in pediatric age groups. Reducing intake of saturated fatty acids, increasing consumption of monounsaturated fatty acids and a balanced intake of omega-3 and omega-6 to reduce the risk of cardiovascular diseases risk factors are recommended.
... Continuous ingestion of medium-chain triglycerides (MCTs) or medium-and longchain triglycerides (MLCTs) to suppress fat accumulation has been compared to ingestion of long-chain triglycerides (LCTs) [12][13][14][15][16]. Continuous ingestion of MCTs to enhance fat oxidation during low-intensity physical activity was reported over the effect of LCTs [7,17]. ...
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The elimination of obesity is essential to maintaining good health. Medium-chain triglycerides (MCTs) inhibit fat accumulation. However, studies examining energy expenditure and fat oxidation with continuous ingestion of MCTs show little association with the elimination of obesity. In this study, we conducted a randomized, double-blind crossover clinical trial to investigate the effects of continuous ingestion of MCTs on postprandial energy expenditure and ingested long-chain triglycerides (LCTs) oxidation. A daily 2 g of MCTs were ingested for two weeks by sedentary participants with a body mass index (BMI) from 25 (kg/m2) to less than 30. Ingestion of a meal containing MCTs and isotopic carbon-13-labeled (13C) LCTs increased energy expenditure and consumption of diet-derived LCTs, as determined by postprandial 13C carbon dioxide excretion, compared to canola oil as the placebo control. These results indicate that continuous ingestion of MCTs could enhance postprandial degradation of diet-derived fat and energy expenditure in sedentary, overweight individuals.
... Opposed to these results, no matter the higher level of C18:0 in the NW group or the higher levels of C13:0 and C20:0 in the erythrocyte membranes, the OB group had a preference for better cognitive function in our study. As a mediumchain fatty acid (MCFA) [52], lauric acid (C12:0) could prevent obesity [53] and reduce neuroinflammatory responses [54], which might be the reasons associated with the higher cognitive function [55]. Accordingly, it could be speculated that tridecyl acid (C13:0) might also act as a protective factor for cognitive function. ...
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Dietary fatty acid intake is closely related to the cognitive function of the overweight and obese population. However, few studies have specified the correlation between exact fatty acids and cognitive functions in different body mass index (BMI) groups. We aimed to explain these relationships and reference guiding principles for the fatty acid intake of the overweight and obese population. Normal weight, overweight, and obese participants were recruited to receive a cognitive function assessment and dietary survey, dietary fatty acids intake was calculated, and the erythrocyte membrane fatty acid profile was tested by performing a gas chromatography analysis. The percentages of saturated fatty acids (SFAs) in the obese group were higher, while monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) were lower than in the normal weight and overweight groups. In the erythrocyte membrane, the increase of n-3 PUFAs was accompanied by cognitive decline in the overweight group, which could be a protective factor for cognitive function in the obese group. High n-6 PUFAs intake could exacerbate the cognitive decline in the obese population. Dietary fatty acid intake had different effects on the cognitive function of overweight and obese people, especially the protective effect of n-3 PUFAs; more precise dietary advice is needed to prevent cognitive impairment.
... MCT can enter the mitochondria without a carnitine shuttle for β-oxidation, and then produce excessive acetyl-CoA and increase the production of ketone bodies as another energy source for the brain, heart and kidneys, thus preventing fat mass accumulation (13). Results from human studies have indicated that MCT consumption could decrease body weight (14) and alter lipid profiles in overweight or obese individuals (15). There are few studies advocating the effects of a ketogenic diet or MCT in terms of improving fertility, and most have focused on female fertility (16). ...
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The study aimed to determine effects of a ketogenic diet on metabolic dysfunction, testicular antioxidant capacity, apoptosis, inflammation, and spermatogenesis in a high-fat and high-cholesterol diet-induced obese mice model. Forty-two male C57BL/6 mice were fed either a normal diet (NC group) or a high-fat and high-cholesterol (HFC) diet (HFC group) for 16 weeks, and mice from the HFC group were later randomly divided into two groups: the first were maintained on the original HFC diet, and the second were fed a medium-chain triacylglycerol (MCT)-based ketogenic diet for 8 weeks (KD group). A poor semen quality was observed in the HFC group, but this was eliminated by the ketogenic diet. Both the HFC and KD groups exhibited enhanced apoptosis protein expressions in testis tissue, including caspase 3 and cleaved PARP, and higher inflammation protein expressions, including TNF-α and NF-κB. However, the KD group exhibited a statistically-significant reduction in lipid peroxidation and an increased glutathione peroxidase level as compared with the HFC group. The HFC diet induced obesity in mice, which developed body weight gain, abnormal relative organ weights, metabolic dysfunction, and liver injury. Overall, the results showed that a ketogenic diet attenuated oxidative stress and improved the semen quality reduced by the HFC diet.
... Despite the consumption of VCO with high saturated fatty acids (SFA) B.W. gain in HFD-VCO-2, Anti-hyperlipidemic and cardio-protective effects of virgin coconut oil metabolized into energy thereby avoiding the accumulation of fat in the body [19]. Consistent with the effect of substitution of medium-chain triglycerides (MCTs) for longchain triglycerides (LCTs) in weight loss, this study has proven that administration of VCO evokes significant reduction in BMI of male Wistar rats [20]. Additionally, the accumulation of epididymal and retroperitoneal fat has substantially been attenuated in HFD ? ...
Article
Effects of hot process-derived virgin coconut oil (VCO) on antiobesity, lipid-lowering and cardio-protection in male Wistar rat models fed with high-fat diet (HFD) were investigated for 7 weeks. The marked increase in body weight, liver weight, epididymal fat weight, and specific growth rate of HFD-fed rats were significantly attenuated when the HFD was supplemented with VCO. Serum lipid profile of VCO-fed rats showed significantly reduced levels of triglycerides, total cholesterol, low and very low-density lipoprotein cholesterol, and non-high-density lipoprotein cholesterol (non-HDL-C), and increment in high-density lipoprotein cholesterol (HDL-C) level. Significant decrease in cardiac risk indices and CHOLINDEX in all the VCO-treated animal groups were observed. Hepatic enzymatic biomarkers associated with HFD-induced liver damage were reversed with the VCO supplementation. Thus, dose-dependent VCO supplementation can be considered as an effective dietary approach to attenuate obesity and to alleviate the risks of cardiovascular diseases.
... Tyler Maher et al., have been suggested that consumption of MCT reduces energy intake in the subsequent 48 h, whereas conjugated linoleic acid does not. This may be mediated by increased β-HB concentrations or via delayed gastric emptying, which in turn may lead to prolonged elevated PYY concentrations (Mumme and Stonehouse, 2015). A Meta-Analysis of randomized controlled trials has been concluded that replacement of LCTs with MCTs in the diet could potentially induce modest reductions in body weight and composition without adversely affecting lipid profiles (St-Onge & Jones, 2002). ...
Article
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Medium chain fatty acids (MCFAs) has unique transport system and is rapidly metabolized in the body. It mainly occurs in coconut oil, palm kernel oil and milk products. Dietary supplementation with MCFAs can improve metabolic features as well as cognition in humans. Some of the effects of MCFAs may be through direct receptor-mediated intracellular pathways, but MCFAs are also metabolic regulators that can alter circulating levels of hormones and metabolites, and hence may indirectly mediate body metabolism. Here we describe how dietary medium chain fatty acid, previously found to improve immune response and insulin secretion via G-protein coupled receptors, can increase apoptosis in cancer cells through the activation of the EGFR/ERK/AP1 trans-duction pathway. MCFA-enriched diets could therefore be used to manage metabolic diseases through the modification of gut microbiota, activation of GPR 40 and GPR 84.
... Since kMCT are only found at very low levels in adipocytes and in the diet, they need to be repeatedly ingested to ensure their transformation into ketones within the liver (143) . In cognitively healthy young and older adults, kMCT reduce postprandial glucose (144) , have a neutral effect on fasting lipids and glucose and can moderately reduce body weight (-0·5 kg) (145,146) . The consumption of kMCT in MCI and AD for 4-24 weeks is safe and has no significant effects on body weight or plasma cardiometabolic and inflammatory marker profiles (147,148) . ...
Article
Alzheimer’s disease (AD) is the most common major neurocognitive disorder of aging. Although largely ignored until about a decade ago, accumulating evidence suggests that deteriorating brain energy metabolism plays a key role in the development and/or progression of AD-associated cognitive decline. Brain glucose hypometabolism is a well-established biomarker in AD but was mostly assumed to be a consequence of neuronal dysfunction and death. However, its presence in cognitively asymptomatic populations at higher risk of AD strongly suggests that it is actually a pre-symptomatic component in the development of AD. The question then arises as to whether progressive AD-related cognitive decline could be prevented or slowed down by correcting or bypassing this progressive ‘brain energy gap’. In this review, we provide an overview of research on brain glucose and ketone metabolism in AD and its prodromal condition – mild cognitive impairment (MCI) - to provide a clearer basis for proposing keto-therapeutics as a strategy for brain energy rescue in AD. We also discuss studies using ketogenic interventions and their impact on plasma ketone levels, brain energetics and cognitive performance in MCI and AD. Given that exercise has several overlapping metabolic effects with ketones, we propose that in combination these two approaches might be synergistic for brain health during aging. As cause-and-effect relationships between the different hallmarks of AD are emerging, further research efforts should focus on optimizing the efficacy, acceptability and accessibility of keto-therapeutics in AD and populations at risk of AD.
... A meta-analysis on the effects of MCTs on weight loss and body composition reported that MCTs did not significantly improve blood lipid concentrations (specifically of total cholesterol, LDL cholesterol, and HDL cholesterol) when compared to multiple comparison arms (41). However, studies included in this particular analysis were drawn from those identified as part of a literature search aimed at identifying articles relating to weight loss and body composition (i.e., blood lipids were not incorporated in the search terms), and included more complex interventions that did not focus solely on MCTs. ...
Article
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Background Dietary saturated fat raises total cholesterol and LDL cholesterol levels. It is unclear whether these effects differ by the fatty acid chain lengths of saturated fats; particularly, it is unclear whether medium-chain fatty acids increase lipid levels. Objectives We conducted a systematic review to determine the effects of medium-chain triglyceride (MCT) oil, consisting almost exclusively of medium-chain fatty acids (6:0–10:0), on blood lipids. Methods We searched Medline and Embase through March 2020 for randomized trials with a minimum 2-week intervention period that compared MCT oil with another fat or oil. Outcomes were total cholesterol, LDL cholesterol, HDL cholesterol, and triglyceride levels. Included studies were restricted to adults above 18 years of age. Studies conducted in populations receiving enteral or parenteral nutrition were excluded. Data were pooled using a random-effects meta-analysis. Results Seven articles were included in the meta-analysis; LDL cholesterol and HDL cholesterol were reported in 6 studies. MCT oil intake did not affect total cholesterol (0.04 mmol/L; 95% CI, −0.11 to 0.20; I2 = 33.6%), LDL cholesterol (0.02 mmol/L; 95% CI, −0.13 to 0.17; I2 = 28.7%), or HDL cholesterol (−0.01 mmol/L; 95% CI, −0.10 to 0.09; I2 = 74.1%) levels, but did increase triglycerides (0.14 mmol/L; 95% CI, 0.01–0.27; I2 = 42.8%). Subgroup analyses showed that the effects of MCT oil on total cholesterol and LDL cholesterol differed based on the fatty acid profile of the control oil (Pinteraction = 0.003 and 0.008, respectively), with MCT oil increasing total cholesterol and LDL cholesterol when compared to a comparator consisting predominantly of unsaturated fatty acids, and with some evidence for reductions when compared to longer-chain SFAs. Conclusions MCT oil does not affect total cholesterol, LDL cholesterol, or HDL cholesterol levels, but does cause a small increase in triglycerides.
... In addition, the medium-chain saturated fatty acids are becoming more and more interesting for nutritionists. The consumption of these fatty acids causes slight weight loss without any negative effect on lipid metabolism [47]. Gómez-Cortés et al. [48] summarized the SMCSFA's potential benefits in human health in a review report. ...
Article
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The aim of this study was to evaluate the effect of the Schizochytrium limacinum marine algae on the milk composition and fatty acid profile, somatic cell count, and prevalence of pathogen bacteria in the raw milk of multiparous Alpine goats. Twenty-eight dairy goats were randomly allocated to two groups: control group (C)—fed with 1500 g alfalfa hay and 600 g concentrate; experimental group (MA)—received the same forages and concentrate supplemented with 10 g/head/day marine algae. The goats were housed indoors, while the experiment lasted five weeks, and the milk samples were taken every week. Marine algae feeding had no negative effect on milk composition. The marine algae inclusion significantly decreased the milk somatic cell count and the presence of udder pathogens in the MA group. Mean somatic cell count and presence of udder pathogens were 5.73 log cells/mL and 31%, respectively, in the C group, while these values were 5.34 log cells/mL and 10%, respectively, in the MA group. The marine algae supplementation significantly increased DHA and rumenic acid concentration in the milk of the MA group (0.32 and 0.99 g/100 g of fatty acids, respectively) compared to the C group (0.04 and 0.65 g/100 g of fatty acids, respectively). It can be concluded that a diet supplemented with marine algae significantly improves the udder health of goats and the concentrations of health-promoting fatty acids in milk.
... The consumption of MCT has been globally accepted as a dietary treatment against not only refractory epilepsy in children as well as adults but also against a number of other neurodegenerative disorders and metabolic disorders 11 in addition to the over the counter use to reduce body weight 13 . Here, we report for the first time that octanoic acid, one of the major components of MCT ketogenic diet, is detrimental to bone and requires caution in patients susceptible to bone depletion. ...
Article
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Octanoic acid is a medium-chained saturated fatty acid found abundantly in the ketogenic dietary supplements containing medium chained triglycerides (MCT) along with decanoic acid. The MCT ketogenic diet is commonly consumed for weight loss but has also showcased neuroprotective potential against neurodegenerative disorders. However, recent clinical findings have reported a critical disadvantage with the long-term consumption of ketogenic diet i.e. bone loss. The following study was employed to investigate whether the two major components of MCT diet also possess bone loss potential as observed with classical ketogenic diet. Swiss albino mice aged between 10 and 12 weeks, were divided into 3 treatment groups that were administered with oral suspensions of octanoic acid, decanoic acid and a combination of both for 4 weeks. Bone specific markers, microarchitectural parameters, using micro computed tomography, and biomechanical strength were analyzed. Remarkably deleterious alterations in the trabecular bone microarchitecture, and on bone markers were observed in the octanoic acid treated groups. Our results suggest significant negative effects on bone health by octanoic acid. These findings require further investigation and validation in order to provide significant clinically relevant data to possibly modify dietary composition of the MCT ketogenic diet.
... Since a long time, synthetic medium-chain triacylglycerols (MCT) with fatty acid (FA) chain length of 8 and/or 10 carbon atoms have been used in parenteral nutrition [3] and as freely available food supplements ("MCT-Oil"). Further, triacylglycerols originating from coconut-or palm kernel oil and milk fat [4] that contain mediumchain fatty acids (MCFA-TGs) with mostly 12 carbon atoms are becoming an increasingly important part of general nutrition [5]. Several possible positive associations suggest MCFA-TGs as a healthy alternative to normal long-chain FA containing TGs (LCFA-TGs) [6,7]. ...
Article
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Objective Medium-chain fatty acids (MCFAs) play an increasing role in human nutrition. In the liver, one fraction is used for synthesis of MCFA-containing triacylglycerol (MCFA-TG), the rest is used for oxidative energy production or ketogenesis. We investigated which enzymes catalyze the synthesis of MCFA-TG and how inhibition of MCFA-TG synthesis or fatty acid (FA) oxidation influences the metabolic fate of the MCFAs. Methods Fatty acid metabolism was followed by time-resolved tracing of alkyne-labeled FAs in freshly isolated mouse hepatocytes. Quantitative data were obtained by mass spectrometry of several hundred labeled lipid species. Wildtype hepatocytes as well as cells from diacylglycerol acyltransferase (DGAT)1-/- mice were treated with inhibitors against DGAT1, DGAT2, or FA β-oxidation. Results Inhibition or deletion of DGAT1 resulted in a reduction of MCFA-TG synthesis by 70%, while long-chain (LC)FA-TG synthesis was reduced by 20%. In contrast, DGAT2 inhibition increased MCFA-TG formation by 50%, while LCFA-TG synthesis was reduced by 5-25%. Inhibition of β-oxidation by the specific inhibitor teglicar strongly increased MCFA-TG synthesis. In contrast, the widely used β-oxidation inhibitor etomoxir blocked MCFA-TG synthesis, phenocopying DGAT1 inhibition. Conclusions DGAT1 is the major enzyme for hepatic MCFA-TG synthesis. Its loss can only partially be compensated by DGAT2. Specific inhibition of β-oxidation gives rise to a compensatory increase in MCFA-TG synthesis, whereas etomoxir blocks both β-oxidation and MCFA-TG synthesis, indicating a strong off-target effect on DGAT1.
... Studies in human also showed that MCT increased oxidation of fat and thermogenesis more than LCT in both short and long-term periods of supplementation [20,21]. Moreover, consumption of both LCT and MCT not only have the potential to induce the reduction of body weight but they do so without changing lipid profiles [22]. However, the consumption of MCT may result in greater satiety due to the difference in its digestion and absorption as well as in the consequent effects on β-oxidation [23][24][25]. ...
Article
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Medium-Chain Fatty Acids (MCFA) are saturated fats with aliphatic rings of 6-12 carbons. It is widely accepted that the metabolism of MCFA induces ketogenesis in the liver. Ketone bodies have been suggested to produce larger amounts of energy compared to glucose. Its benefit in providing an alternative source of energy has been as one of the strategies to prevent disease development especially those diseases that are associated with glucose metabolism or mitochondrial dysfunction. The current review highlights the nutritional impacts of MCFA and its utilization in disease therapy.
... Zicker et al. have shown that a high carbohydrate diet supplemented with coconut oil, which is rich in MCSFAs, promoted lower adiposity and decreased hepatic steatosis in mice compared to a high carbohydrate diet alone [12]. MCSFAs are also effective in reducing body weight and adiposity [13] and in improving exercise endurance in human subjects [14]. It should be pointed out that most of these studies on MCSFAs have used coconut oil as a source of these fatty acids. ...
Article
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Simple Summary: The aim of this study was to compare the effect of palmitic acid (PA), a long-chain fatty acid, and lauric acid (LA), a medium-chain fatty acid, on obesity-related metabolic disorders. We used a mouse model of diet-induced obesity and fed them a modified high fat diet supplemented with 3% PA or LA for 12 wk. An LA diet led to an increase in visceral fat mass with a reduction in inflammation compared to the PA diet. We also noted that PA significantly increased systemic insulin resistance whereas LA showed only a trend towards an increase compared to lean control mice. The expression of a protein involved in muscle glucose uptake was higher in LA-treated mice compared to the PA-treated group, indicating improved muscle glucose uptake in LA-fed mice. Analysis of liver samples showed that hepatic steatosis was higher in both PA and LA-fed mice compared to lean controls. Markers of liver inflammation were not altered significantly in mice receiving PA or LA. Our data suggest that compared to PA, LA exerts less adverse effects on metabolic disorders and this could be due to the differential effects of these fatty acids in fat and muscle. Abstract: Coconut oil, rich in medium-chain saturated fatty acids (MCSFA), in particular, lauric acid (LA), is known to exert beneficial metabolic effects. Although LA is the most abundant saturated fatty acid in coconut oil, the specific role of LA in altering obesity-related metabolic disorders remains unknown. Here, we examined the effects of supplementing a high fat (HF) diet with purified LA on obesity-associated metabolic derangements in comparison with palmitic acid (PA), a long-chain saturated fatty acid. Male C57BL/6 mice were fed a control chow diet (CD) or an HF diet supplemented with 3% LA (HF + LA) or PA (HF + PA) for 12 wk. Markers of adipose tissue (AT) inflammation, systemic insulin resistance (IR), and hepatic steatosis, were assessed. The body weight and total fat mass were significantly higher in both HF + LA and HF + PA diet-fed groups compared to CD controls. However, the visceral adipose tissue (VAT) mass was significantly higher (p < 0.001) in HF + LA-fed mice compared to both CD as well as HF + PA-fed mice. Interestingly, markers of AT inflammation were promoted to a lesser extent in HF + LA-fed mice compared to HF + PA-fed mice. Thus, immunohistochemical analysis of VAT showed an increase in MCP-1 and IL-6 staining in HF + PA-fed mice but not in HF + LA-fed mice compared to CD controls. Further, the mRNA levels of macrophage and inflammatory markers were significantly higher in HF + PA-fed mice (p < 0.001) whereas these markers were increased to a lesser extent in HF + LA-fed group. Of note, the insulin tolerance test revealed that IR was significantly increased only in HF + PA-fed mice but not in HF + LA-fed group compared to CD controls. While liver triglycerides were increased Biology 2020, 9, 346 2 of 17 significantly in both HF + PA and HF + LA-fed mice, liver weight and plasma markers of liver injury such as alanine aminotransferase and aspartate aminotransferase were increased significantly only in HF + PA-fed mice but not in HF + LA-fed mice. Taken together, our data suggest that although both LA and PA increased AT inflammation, systemic IR, and liver injury, the extent of metabolic derangements caused by LA was less compared to PA in the setting of high fat feeding.
... Coconut oil is rapidly metabolized, readily ingested and LA is well transported and helps scales back the fat collection. LA shows significant antimicrobial action against grampositive microorganisms and load of parasites and infections as confirmed by various investigations (Mumme and Stonehouse, 2015). ...
Article
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The study was designed to investigate the neuro-protection of lauric acid (LA) on haloperidol (HPD) induced Parkinson's disease (PkD) rat model. Rats were divided into group A (normal), group B (diseased, by HPD 1mg/kg i.p. for 14 days), group C (standard treatment, levodopa 30 mg/kg), group D (vehicle coconut oil 1ml/kg), group E (LA 0.66mg/kg) and group F (LA 1.32mg/kg) for 35 days after induction of PkD. The study displayed a state of oxidative stress in the striatum of rat model of PkD as shown from the increased MDA, NO levels and the decreased superoxide dismutase levels. HPD caused an increase in tumor necrosis factor-α level, NF-κB, IL-8 mRNA expression and suppress IL-4 expression. Neuro-protection with LA attenuated the oxidative stress and changes in pro-inflammatory cytokines induced due to PkD induction. The LA treatment also showed improvement in the histo-pathology of the rats' brain. LA also improved behavioral performances, food intake, weight gain as compared to animal of diseased group and prevented decline in motor activities (assessed Rotarod, and Beam walking test). LA showed significant neuro-protection against oxidative stress, inflammatory cytokines and behavioral changes in HPD induced rat model of PkD.
... Their ingestion also influences gene expressions in various organs that suppress fat deposition, cause an increase in both β-oxidation and energy expenditure [51,52]. Similarly, the medium chain fatty acids are said to cause increased fat oxidation and energy expenditure [53,54]. On the other hand, higher intake of long-chain SFAs such as myristic, palmitic and stearic acids tend to favor higher values of LI, AI and TI [31,32]. ...
... As a result of this alternation in feeding and fasting periods, metabolic alterations consequently occur to cope with the changes in energy supply and energy shortage, respectively. Halting intakes of dietary long-chain fatty acids (LCFA) and supplementation with medium-chain triglycerides (MCTs) can result in negative energy balance and weight loss by increasing host energy expenditure and lipid oxidation, which disfavor the microenvironment of viral replication [11]. ...
Article
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Background: COVID-19 pandemic, a global threat, adversely affects all daily lives, altered governmental plans around the world, and urges the development of therapeutics and prophylactics to avoid the expansion of the viral infection. With the recent gradual opening after long lockdown, several recommendations have been placed, with dietary modification as one of the most important approaches that have been appraised. Summary: Here, we are reviewing how changing the host metabolism, particularly changing the host metabolic state from the carbohydrate-dependent glycolytic state to a fat-dependent ketogenic state, may affect viral replication. Furthermore, the impact of intermittent fasting (IF) in triggering metabolic switch along with the impact of supplementation with medium-chain triglycerides (MCTs) such as lauric acid in repressing the envelope formation and viral replication is also addressed. The amalgamation of IF and a ketogenic diet rich in MCTs is thought to work as a prophylactic measure for normal people and adjunct therapy for infected persons. Key Message: A diet regimen of ketogenic breakfast along with supplementation with two doses of lauric acid-rich MCTs at breakfast and lunch times, followed by 8-12-h IF and a dinner rich with fruits and vegetables, could be a potential prophylactic strategy and adjuvant therapy to combat SARS-CoV-2 infections.
... 60 Potential benefits of medium-chain triglycerides include modest weight loss and favorable changes in body composition in comparison with long-chain triglycerides, with similar effects on lipids. 61 Limited data are available regarding the cardiovascular effects of the KD. Short-term KD induces a decrease in high-energy phosphate metabolism by cardiac magnetic resonance imaging spectroscopy, without echocardiographic changes in function. ...
Article
Despite existing therapy, patients with heart failure (HF) experience substantial morbidity and mortality, highlighting the urgent need to identify novel pathophysiological mechanisms and therapies, as well. Traditional models for pharmacological intervention have targeted neurohormonal axes and hemodynamic disturbances in HF. However, several studies have now highlighted the potential for ketone metabolic modulation as a promising treatment paradigm. During the pathophysiological progression of HF, the failing heart reduces fatty acid and glucose oxidation, with associated increases in ketone metabolism. Recent studies indicate that enhanced myocardial ketone use is adaptive in HF, and limited data demonstrate beneficial effects of exogenous ketone therapy in studies of animal models and humans with HF. This review will summarize current evidence supporting a salutary role for ketones in HF including (1) normal myocardial ketone use, (2) alterations in ketone metabolism in the failing heart, (3) effects of therapeutic ketosis in animals and humans with HF, and (4) the potential significance of ketosis associated with sodium-glucose cotransporter 2 inhibitors. Although a number of important questions remain regarding the use of therapeutic ketosis and mechanism of action in HF, current evidence suggests potential benefit, in particular, in HF with reduced ejection fraction, with theoretical rationale for its use in HF with preserved ejection fraction. Although it is early in its study and development, therapeutic ketosis across the spectrum of HF holds significant promise.
... Coconut oil is rapidly metabolized, readily ingested and LA is well transported and helps scales back the fat collection. LA shows significant antimicrobial action against grampositive microorganisms and load of parasites and infections as confirmed by various investigations (Mumme and Stonehouse, 2015). ...
Research
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The research was designed to investigate the neuro-protective effects of LA on haloperidol HPD induced (PkD) rat model
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Objectives The aim of this study is to compare acute effects of consuming extra virgin coconut oil (EVCO) as a source of medium chain fatty acids and extra virgin olive oil (EVOO) as a source of long chain fatty acids in normal weight and obese subjects. Design Randomised, crossover design. Participants Metabolically healthy twenty male subjects (10 normal weight; 10 obese) aged 19–40 years. Intervention Subjects consumed breakfast meals containing skimmed milk, fat-free white cheese, bread and EVCO (25 g) or EVOO (25 g). Outcome measures Visual analog scale evaluations, resting metabolic rate measurements and selected blood parameters analysis (glucose, triglyceride, insulin and plasma peptide YY) were performed before and after the test breakfast meals. In addition, energy intakes were evaluated by ad libitum lunch meal at 180 min. Results Visual analogue scale values of hunger and desire to eat decreased significantly after EVCO consumption than EVOO consumption in normal weight subjects at 180 min. There was an increase trend in plasma PYY at 30 and 180 min after EVCO breakfast compared to EVOO breakfast. Ad libitum energy intakes after EVCO and EVOO consumption in normal weight subjects were 924 ± 302; 845 ± 158 kcal (p = 0.272), respectively whereas in obese subjects were 859 ± 238; 994 ± 265 kcal (p = 0.069) respectively. Conclusion The results of this study shows that consumption of EVCO compared to EVOO may have suppressive effect on hunger and desire to eat, may affect postprandial PYY levels differently and have no effect on postprandial energy expenditure. Trial registration Clinical Trials NCT04738929 .
Article
Background & aims Ketogenic medium-chain-fatty acids (MCFAs) with profound health benefits are commonly found in dairy products, palm kernel oil and coconut oil. We hypothesize that magnesium (Mg) supplementation leads to enhanced gut microbial production of MCFAs and, in turn, increased circulating MCFAs levels. Methods We tested this hypothesis in the Personalized Prevention of Colorectal Cancer Trial (PPCCT) (NCT01105169), a double-blind 2 × 2 factorial randomized controlled trial enrolling 240 participants. Six 24-hour dietary recalls were performed for all participants at the baseline and during the intervention period. Based on the baseline 24-hour dietary recalls, the Mg treatment used a personalized dose of Mg supplementation that would reduce the calcium (Ca): Mg intake ratio to around 2.3. We measured plasma MCFAs, sugars, ketone bodies and tricarboxylic acid cycle (TCA cycle) metabolites using the Metabolon's global Precision Metabolomics™ LC-MS platform. Whole-genome shotgun metagenomics (WGS) sequencing was performed to assess microbiota in stool samples, rectal swabs, and rectal biopsies. Results Personalized Mg treatment (mean dose 216.5 mg/day with a range from 77.25 mg/day to 389.55 mg/day) significantly increased the plasma levels of C7:0, C8:0, and combined C7:0 and C8:0 by 18.45%, 25.28%, and 24.20%, respectively, compared to 14.15%, 10.12%, and 12.62% decreases in the placebo arm. The effects remain significant after adjusting for age, sex, race and baseline level (P=0.0126, P=0.0162, and P=0.0031, respectively) and FDR correction at 0.05 (q=0.0324 for both C7:0 and C8:0). Mg treatment significantly reduced the plasma level of sucrose compared to the placebo arm (P=0.0036 for multivariable-adjusted and P=0.0216 for additional FDR correction model) whereas alterations in daily intakes of sucrose, fructose, glucose, maltose and C8:0 from baseline to the end of trial did not differ between two arms. Mediation analysis showed that combined C7:0 and C8:0 partially mediated the effects of Mg treatment on total and individual ketone bodies (P for indirect effect =0.0045, 0.0043, 0.03, respectively). The changes in plasma levels of C7:0 and C8:0 were significantly and positively correlated with the alterations in stool microbiome α diversity (r=0.51, p=0.0023 and r=0.34, p=0.0497, respectively) as well as in stool abundance for the signatures of MCFAs-related microbiota with acyl-ACP thioesterase gene producing C7:0 (r=0.46, p=0.0067) and C8:0 (r=0.49, p=0.003), respectively, following Mg treatment. Conclusions Optimizing Ca:Mg intake ratios to around 2.3 through 12-week personalized Mg supplementation leads to increased circulating levels of MCFAs (i.e. C7:0 and C8:0), which is attributed to enhanced production from gut microbial fermentation and, maybe, sucrose consumption.
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Background: The aim of this article (scoping review) is to elucidate the current knowledge for the potential role of body weight for setting and updating Dietary Reference Values (DRVs) and Food-Based Dietary Guidelines (FBDGs). The following research questions were formulated:What is known about the association between intakes of specific nutrient and/or foods (exposure/intervention) and body weight (outcome) in the general population?What is known about the association between body weight (exposure) and intakes of specific nutrient and/or foods (outcomes)?Is there any evidence suggesting specific effects of foods or nutrients on body weight independent of caloric content? Methods: To identify potentially relevant articles, PubMed was searched from January 1, 2011 to June 9, 2021. The search strategy was drafted by the NNR2022 Committee. The final results were exported into EndNote. Systematic reviews (SRs), scoping reviews (ScRs), reviews, and meta-analyses (MAs) on the topic 'Body weight' published between January 1, 2011 and June 9, 2021, including human participants from the general population, in English or Scandinavian language (Norwegian, Swedish, or Danish), were considered eligible. Main findings: First, the overall body of evidence based on findings from SRs and MAs of observational and clinical studies indicates that changes in intakes of specific nutrients (sugar, fiber, and fat) and/or foods (sugar sweetened beverages, fiber rich food, and vegetables) are associated with modest or small short-term changes (0.3-1.3 kg) in body weight in the general population (with or without obesity/overweight), while long-term studies are generally lacking. Second, no study in our search assessed any association between body weight (exposure) and intakes of specific nutrients or foods (outcomes). Third, limited evidence suggests, but does not prove, that some foods or nutrients may have specific effects on body weight or body weight measures independent of caloric content (e.g. nuts and dairy). These findings may inform the setting and updating of DRVs and FBDGs in NNR2022.
Article
This study aimed to compare the effects of three different medium chain triglycerides (MCTs) on lipid metabolism in obese rats. A high fat diet was fed to Sprague-Dawley rats to induce obesity, and then caprylic triglyceride (CYT), capric triglyceride (CT) and lauric triglyceride (LT) were synthesized and used to treat the obese rats for 12 weeks. The obesity phenotype and molecular changes related to lipid metabolism were determined. The results showed that all the three MCTs reduced the body weight (BW) and fat coefficient in obese rats, and the levels of plasma and liver lipids were also improved. Among the MCT groups, the LT group showed the lowest BW with the lowest food intake. Furthermore, three MCTs had different effects on the expression levels of lipid metabolism-related proteins (PPARs and SREBPs). The LT group performed the best among the three MCT groups in the protein expression levels. Interestingly, high-dose LT decreased the expression of the low density lipoprotein receptor (LDLR) in the liver, which impaired the transport of the very low density lipoprotein (VLDL)/low density lipoprotein (LDL) to the liver, resulting in high levels of total plasma cholesterol (TC) and LDL-c in the rats. We have for the first time found that different MCTs had different effects on the expression levels of triacylglycerol and cholesterol metabolism-related proteins in obese rats. These findings would help better understand the relationship between the health benefit and the type of MCT.
Article
Background: Oleogels represent one of the most important carriers for the delivery of lipophilic nutraceuticals. Phytosterols (PS), plant-derived natural sterol compounds, are preferred for oleogel preparation due to their self-assembly properties and health function. However, the relationship between the physical properties of PS-based oleogels and the chemical stability of loaded bioactive compounds is still unclear. Results: The influence of lecithin (LC) and glycerol monostearate (GMS) on the physical properties of PS-based oleogels made of liquid coconut oil and the stability of curcumin as a model bioactive loaded in the oleogels was investigated. Results showed that the flow consistency index was much higher for GMS-containing oleogels than that for LC-containing oleogels. The optical microscopy and X-ray scattering analysis showed that the addition of GMS in the PS oleogels promoted the formation of crystal mixture with different crystal polymorph structures, whereas LC addition promoted the formation of needle-like crystals of PS. Using curcumin as a model lipophilic nutraceutical, the GMS-enriched PS oleogels with high crystallinity and flow consistency index exhibited good retention ratio and scavenging activity of the loaded curcumin when stored at room temperature. Conclusion: This study shows that enhancing the firmness of oleogels made from PS and liquid coconut oil is beneficial to the retention and chemical stability of loaded bioactive (curcumin). The findings of the study will boost the development of PS-based oleogel formulations for lipophilic nutraceutical delivery. This article is protected by copyright. All rights reserved.
Chapter
The physiologic state of ketosis is characterized by decreased blood glucose, suppression of insulin, and an increase in the blood ketones β‎-hydroxybutyrate (β‎HB) and acetoacetate (AcAc), which serve as alternative sources of ATP in the brain. Ketones are elevated by fasting, caloric restriction, exercise, or the ketogenic diet (KD), and until recently these were the only known methods of inducing and sustaining ketosis in a nonpathologic setting. Many studies have revealed therapeutic effects of the KD, and data suggest that the benefits are mediated largely by ketone body metabolism and signaling. However, the KD often causes reduced patient compliance, which can make the KD a suboptimal long-term treatment. This has led researchers to develop exogenous ketone supplements—compounds that release or are metabolized into β‎HB and/or AcAc. The supplements rapidly elevate blood ketones in a dose-dependent manner, making them a practical method for inducing therapeutic ketosis. Ketone supplementation could potentially be used as stand-alone therapy in certain conditions, or possibly as a way to further augment the efficacy of the KD in the conditions in which it is being used or investigated, and it could increase compliance by allowing patients to maintain a less restrictive diet. Ketone supplements may also serve as an effective preventative medicine due to their potential to protect and enhance mitochondrial function. Preliminary evidence suggests there are several conditions for which ketone supplementation may be beneficial, including epilepsy, Alzheimer’s disease, glucose transporter type 1 deficiency syndrome, cancer, atrophy-related diseases, and metabolic syndrome.
Chapter
Consumption of functional foods may provide health benefits by reducing risk of many chronic diseases and improve structure and function of the human body. However, in the addition to the positive effect of absorption and digestion of functional ingredients, the interaction between food constituents and bioactives present in functional foods may strongly affect the bioavailability of dietary macronutrients and micronutrients. Gelation of dietary fiber in intestines may decrease digestibility and absorption of fat and carbohydrates but also may affect absorption of calcium, magnesium, and iron. In contrast, inulin and fructooligosaccharides may increase absorption of calcium and magnesium. High consumption of polyphenolic compounds, including tannins, can reduce bioavailability of iron and copper which may be a causative factor of anemia. Tannins present in green tea or its extracts may adversely affect functions. Thiocyanates, present cruciferous vegetables, may decrease iodine availability to the thyroid gland and decrease synthesis of precursors of thyroid hormones. This chapter will address positive and negative effects associated with absorption and digestibility of bioactive compounds.
Article
Medium chain triglycerides (MCT) are important substrates of the energy metabolism and anabolic processes in mammals. In this study, MCT-rich oil was encapsulated in the mixing ratios of maltodextrin and protein by spray drying to produce spray-dried MCT-rich oil (SMCT). Spray-dried conditions were an inlet temperature of 200 °C, an outlet temperature of 90 °C, and a flow rate of 0.70 L/h. Box–Behnken experimental design and response surface methodology were applied for modeling the influence of formulation variables on powder recovery of SMCT. The key variables were concentration of maltodextrin (10-30% W/W), total protein (5–15% w/w), and MCT-rich oil (5–15% w/w). The microparticles were characterized in terms of particle morphology, yield, Carr's index, moisture content, flowability, hygroscopicity, and powder diffraction. The highest yield of SMCT was 41.19% obtained under the optimized conditions (maltodextrin concentration of 15% w/w, total protein concentration of 8% w/w, MCT-rich oil concentration of 15%). Experimentally obtained values were consistent with those predicted by the model, indicating the suitability of the employed model and the success of the model in optimizing the formulation.
Article
Background Designer lipid is a novel, health-friendly lipid with potential application in food, nutraceutical and pharmaceutical industries, including obesity, cancer, heart disease, inflammation. These advantages arise due to modification of fat/oil by the chemical or enzymatic process to form designer lipid. The transformation of lipid results in the rearrangement of fatty acid within a triglyceride molecule or between two different triglycerides. Thus, the resulting designer lipid has superior and unique physicochemical properties than the naturally occurring triglycerides. Due to these excellent physicochemical properties, they are in great demand in the market. Scope and approach The primary aim of this review is to describe component fatty acids used for the synthesis of designer lipids, the process used in designing designer lipids, and reactors used to intensify the yield of designer lipids, application of designer lipid in the food and nutraceutical sector. Key findings and conclusions Designer lipid is a chemically/enzymatically modified form of lipid to improve physicochemical and nutritional properties of traditional lipids coming from plant and animal source. Such fabricated lipids have attracted consumers' attention because of their unique properties and capability to manage various syndromes. Their demand by the consumer increased over the recent past. To fulfil the increase in demand, the intensified synthesis of these designer lipids is carried out using packed bed reactors, ultrasonic reactors, high-pressure reactors. With their claimed health benefits, designer lipids are widely used as a functional ingredient in the food and pharmaceutical industries. Currently, designer lipids are used as a plastic fat, human milk substitute, cocoa butter, used in infant formulation, low-calorie lipids, an anti-cancer, reduced cardiovascular risk etc. The application of designer lipid is governed by the positional distribution and type of fatty acid esterified on the glycerol backbone.
Article
It has been pointed out that excessive intake of fructose is associated with the development of metabolic syndrome. The physiological effects of fats and oils differ greatly depending on the fatty acids they contain. This study compared the effects of different fats and oils in a high fructose diet in rats. When the rats were fed a high fructose diet containing fish oil (FO), soybean oil (SO) or medium-chain triglycerides (MCT) using lard (LD) as a control for 4 weeks, the FO group exhibited a remarkable improvement in lipid metabolism. Although the SO group exhibited a decrease in hepatic lipids, the effect was smaller than that in the FO group. In the MCT group, the expression of genes related to fatty acid synthesis in mesenteric fat was remarkably high, and no improvement of lipid metabolism was observed. The hepatic protein expression profile in the FO group differed from that in the other groups. Increased protein expression associated with fatty acid oxidation and the oxidative stress response was observed in the FO group. These results revealed a difference in the physiological effects of fats and oils in a high fructose diet.
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Long-chain triglycerides (LCTs) intake strongly stimulates GIP secretion from enteroendocrine K cells and induces obesity and insulin resistance partly due to GIP hypersecretion. In this study, we found that medium-chain triglycerides (MCTs) inhibit GIP secretion after single LCT ingestion and clarified the mechanism underlying MCT-induced inhibition of GIP secretion. MCTs reduced the CCK effect after single LCT ingestion in wild-type (WT) mice, and a CCK agonist completely reversed MCT-induced inhibition of GIP secretion. In vitro studies showed that medium-chain fatty acids (MCFAs) inhibit long-chain fatty acid (LCFA)-stimulated CCK secretion and increase in intracellular Ca²⁺ concentrations through inhibition of GPR120 signaling. Long-term administration of MCTs reduced obesity and insulin resistance in high-LCT diet-fed WT mice, but not in high-LCT diet-fed GIP-knockout mice. Thus, MCT-induced inhibition of GIP hypersecretion reduces obesity and insulin resistance under high-LCT diet feeding condition.
Article
The relationship between saturated fatty acid (SFA) consumption and the risk of overweight/obesity remains unclear. Epidemiological evidence is lacking among Chinese population. This study aimed to investigate the association between individual dietary SFA intake and the risk of overweight/obesity in Chinese adults. Data from 8,465 adults with BMI <24 at entry in the China Health and Nutrition Survey (CHNS, 1989-2011) were analysed. Three-day 24-h dietary records were used to collect dietary data. Cox proportional hazard regression models were constructed to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the risk of developing overweight or obesity. A total of 3,171 incident cases of overweight/obesity were identified (1,649 for women and 1,522 for men) during a median of 11 years of follow-up. Compared with the lowest category, the intake of total SFAs (TSFAs) showed no significant association with the risk of overweight/obesity. However, an increased risk of overweight/obesity was observed with a higher intake of medium chain SFAs (MCSFAs) (P-trend = 0.004), especially decanoic acid (10:0) [HR (95% CI) was 1.25 (1.10-1.42) comparing the highest category with the reference group; P-trend<0.001), whereas an inverse relationship was observed for hexanoic acid (6:0) consumption; compared with non-consumers, 6:0 intake was associated with 32% lower risk of overweight/obesity [HR (95% CI): 0.68 (0.56-0.84); P-trend<0.001]. Overall, the intake of subtypes of MCSFAs but not TSFA was associated with the risk of overweight/obesity. Increasing hexanoic acid (6:0) and limiting decanoic acid (10:0) consumption may be protective for overweight/obesity among Chinese population.
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After the SARS-CoV-2 epidemic starting in early 2020, a novel strategy was tried: "flattening the curve" by isolating everybody until a vaccine would become available. A year later, however, the coronavirus (CoV) vaccines faced a similar problem as influenza vaccines. Strains resistant to natural and vaccine-induced immunity against previous strains started a new epidemic. Interrupting this vicious cycle requires strategies safer than treatments, because few people (<0.1%) would die, and more flexible than vaccines. To be replicated, viruses need to be endocytosed by human cells. Endocytosis is regulated by phos-phoinositides derived from phospholipids (PLs). PLs are also split by cPLA2 into the lyso-PLs needed to replicate virus RNA and to assemble the next progeny and into inflammatory arachidonic acid. As overactive endocytosis also drives breast cancer (BCa) metastases and neurodegeneration, the same mechanism of action underlying novel treatments there might also reduce replication of respiratory disease viruses (RDV) including CoV. In vivo results in BCa and neurodegeneration confirmed that alpha-cyclodextrins (αCDs) scavenging serum PLs reduce endocytosis and, thus, CoV replication. Manuscript File Click here to view linked References KNUT M. WITTKOWSKI (4/28/2021)-2-2 CDs are typically infused overnight, but from recent human PK/PD studies, clathrates (inclusion complexes) of αCDs with capric acid (C10), from milkfat or coconut oil, are intestinally absorbed after oral administration. Moreover, both compounds clinically improve cardio-metabolic functions involved in comorbid-ities (obesity, diabetes, atherosclerosis) of COVID. The clathrate is GRAS (generally recognized as safe) and, thus, can be used as part of a nutritional intervention during "flu" seasons. With deaths from COVID substantially reduced, universal mitigation would finally become obsolete.
Article
Background and Aims There is some promising evidence regarding the beneficial effect of coconut oil on cardiometabolic risk factors. This study aimed to assess the effects of virgin coconut oil (VCO) consumption on metabolic syndrome (MetS) components, as well as, asymmetric dimethylarginine (ADMA) in adults with MetS. Methods and Results In this randomized controlled trial, 48 subjects, aged 20–50 years, with MetS were allocated into two groups; the intervention group was given 30 ml of VCO per day to substitute the same amounts of fat in their usual diet for four weeks. The control group was advised to follow their usual diet. VCO consumption significantly reduced serum levels of triglyceride (TG) (P=0.001), very low-density lipoprotein (VLDL) (P=0.001), and fasting blood sugar (FBS) (P=0.015) compared to the control group. The levels of high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and total cholesterol (TC) were significantly increased in the VCO group when compared to the control group (P=0.001). Circulatory ADMA also increased in the VCO group compared to the control group (P=0.003). No significant differences were observed in the LDL-C/HDL-C ratio, anthropometric parameters, and blood pressure measurements between the two groups at the end of the study (P>0.05). Conclusion VCO consumption increased the values of HDL-C while reduced TG and FBS levels. Blood pressure and waist circumference did not change. However, levels of TC, LDL-C, and ADMA elevated by VCO consumption. Caution is warranted until the results of further studies become available to explain the long-term effects of VCO consumption. Registration number IRCT20131125015536N11
Article
Lauric acid (LA) has been implicated in the prevention/treatment of obesity. However, the role of LA in modulating an obesity-related female reproductive disorder remains largely unknown. Here, female mice were fed a control diet, high-fat diet (HFD), or HFD supplemented with 1% LA. The results demonstrated that the HFD-induced estrous cycle irregularity and the reduction of serum follicle-stimulating hormone (FSH) were alleviated by LA supplementation. In possible mechanisms, LA supplementation led to significant increase in serum lipid metabolites such as sphingomyelin and lysophosphatidylcholine containing LA (C12:0) and the improvement of glucose metabolism in mice fed HFD. Moreover, impaired body energy metabolism and weakened brown adipose tissue (BAT) thermogenesis of HFD-fed mice were improved by LA supplementation. Together, these findings showed that LA supplementation alleviated HFD-induced estrous cycle irregularity, possibly associated with altered serum lipid metabolites, improved glucose metabolism, body energy metabolism, and BAT thermogenesis. These findings suggested the potential application of LA in alleviating obesity and its related reproductive disorders.
Article
Several studies in hepatocyte cell lines reported that medium-chain fatty acids (MCFAs) with 6-12 carbons showed different metabolic properties from long-chain fatty acids (LCFAs). However, these studies reported unclear effects of different fatty acid molecules on hepatocyte metabolism. This study is aimed to capture the metabolic kinetics of MCFA assimilation in AML12 cells treated with octanoic acid (FA 8:0), decanoic acid (FA 10:0), or lauric acid (FA12:0) [LCFA; oleic acid (FA 18:1)] via metabolic profiling and dynamic metabolome analysis with 13C-labeling. The concentrations of total ketone bodies in the media of cells treated with FA 8:0 or FA 10:0 were 3.22- or 3.69-fold higher than those obtained with FA 18:1 treatment, respectively. FA 12:0 treatment did not significantly increase ketone body levels compared to DMSO treatment (control), whereas FA 12:0 treatment increased intracellular triacylglycerol (TG) levels 15.4 times compared to the control. Metabolic profiles of FA 12:0-treated samples differed from those of the FA 8:0-treated and FA 10:0-treated samples, suggesting that metabolic assimilation of MCFAs differed significantly depending on the MCFA type. Furthermore, the dynamic metabolome analysis clearly revealed that FA 8:0 was rapidly and quantitatively oxidized to acetyl-CoA and assimilated into ketone bodies, citrate cycle intermediates, and glucogenic amino acids but not readily into TGs.
Article
Single natural vegetable oils may have some drawbacks in terms of structure and function. Enzymatic interesterification can greatly improve the quality of natural vegetable oils. In this study, soybean oil (SO) and coconut oil (CO) were combined to synthesize structured lipids (SLs) using Lipozyme RM IM as a catalyst to modify the structure of coconut oil, which can make coconut oil have better physicochemical properties. A total of 55.73% structured lipids of total triacylglycerols were synthesized under the optimum reaction conditions. The main fatty acids of SL‐SOCO were linoleic (C18:2, 37.11%), oleic (C18:1, 21.73%) and lauric (C12:0, 14.05%). The most abundant TAG species in SL‐SOCO were (14:0‐18:1‐18:3), (12:0‐14:0‐18:3) and (14:0‐14:0‐18:3) with the relative content of 10.56%, 7.13%, and 5.52%, respectively. Compared to the crystallization curves of SOCO, SL‐SOCO showed a delayed crystallization and a decreased enthalpy. Moreover, the curcumin nanocarrier prepared by SL‐SOCO as the oil phase has good stability, encapsulation efficiency (91.12%) and improved bioavailability (54.02%). To conclude, SL‐SOCO with monounsaturated fatty acid (MUFA), polyunsaturated fatty acids (PUFAs) and medium‐chain fatty acids (MCFAs) has good structural composition and SL‐SOCO nanoparticles has excellent applications in drug delivery system. Practical applications : The prepared SLs can used as one kind of functional lipids, which has the potential to improve lipid metabolism. In addition, it can be used as an oil phase to prepare carriers for encapsulate active substances, which has good stability, improved encapsulation efficiency and bioavailability. This article is protected by copyright. All rights reserved
Article
It has been reported that medium-chain triglyceride (MCT) have various physiological functions, such as anti-obesity and hypolipidemic effects. They can also elicit increased disaccharidase activity and intestinal cell proliferation. However, a meta-analysis of randomized controlled trials, comparing the effects of MCT on weight loss and body composition, detected commercial bias. Additional research on the physiological functions is needed in order to have conclusive evidence. Thus, we sought to evaluate the various functions of MCT by conducting a feeding study in rats. Rats fed a diet containing 15% (w/w) MCT, had significantly lower visceral fat weight, plasma and liver lipid concentrations; they had significantly higher intestinal maltase and glucoamylase activities; and they had a greater number of Ki-67 positive cells/crypt, compared to the rats fed a diet containing 15% (w/w) lard. The effects of a diet containing 5% (w/w) MCT was observed only for plasma cholesterol levels and the number of Ki-67 positive cells/crypt; in which some results were found to be inconsistent with previous reports. These results indicate that physiological functions of MCT are numerous and need to be confirmed by additional research.
Article
Accumulating evidence has suggested that medium-, long-, and medium-chain (MLM) structured lipids have anti-obesity effects, but whether they can alleviate the development of atherosclerosis (AS) and affect the composition of the gut microbiota in high-fat diet-fed ApoE−/− mice has not been elucidated. The present study found that MLM structured lipid supplementation could significantly decrease obesity-related parameters compared with high-fat diet alone in ApoE−/− mice. Additionally, MLM structured lipids could significantly decrease the blood glucose and increase the serum total antioxidant capacity (T-AOC) and superoxide dismutase (SOD) levels. Additionally, high-dose MLM structured lipids supplementation could reduce the area of atherosclerotic lesions and decrease the expression of VCAM-1, MCP-1 and CD68, which are related to inflammation in aortic tissue. Further analysis showed that MLM structured lipids could significantly reduce lipid accumulation in the adipose tissue of high-fat diet-fed ApoE−/− mice. The relative protein expression of SREBP-1, ACC, FAS, C/EBPα and PPARγ was decreased and the ratio of p-AMPK/AMPK was increased in epididymis white adipose tissue (eWAT) after MLM structured lipids treatment. Additionally, MLM structured lipids supplementation regulated the bacterial composition, including reducing the Firmicutes/Bacteroidetes ratio, increasing the relative abundance of short-chain fatty acid-producing bacteria (Blautia and Anaerotruncus), decreasing the relative abundance of [Ruminococcus] torques group, Ruminiclostridium 9, Catenibacterium and [Eubacterium] fissicatena group. Spearman's correlation analysis revealed significant correlations between changes in the gut microbiota and atherosclerosis-related indices. The results demonstrated that the alleviating effects of MLM structured lipids supplementation on AS in high-fat diet-fed ApoE−/− mice were closely related to reshaping the composition of the gut microbiota.
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There has been significant public debate about the susceptibility of research to biases of various kinds. The dialogue has extended to the peer-reviewed literature, scientific conferences, the mass media, government advisory bodies, and beyond. Although biases can come from myriad sources, the overwhelming focus of the discussion, to date, has been on industry-funded science. Given the critical role that the industry has played and will continue to play in the research process, the International Life Sciences Institute North America Working Group on Guiding Principles has, in this article, set out proposed conflict-of-interest guidelines regarding industry funding for protecting the integrity and credibility of the scientific record, particularly with respect to health, nutrition, and food-safety science. Eight principles are enumerated, specifying ground rules for industry-sponsored research. The article, which issues a challenge to the broader scientific community to address all bias issues, is only a first step; the document is intended to be dynamic, prompting ongoing discussion and refinement.
Conference Paper
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This paper presents a genetic algorithm (GA) for the procedural generation of levels in the Angry Birds game. The GA evaluates the levels based on a simulation which measures the elements' movement during a period of time. The algorithm's objective is to minimize this metric to generate stable structures. The level evaluation also considers some restrictions, leading the levels to have certain characteristics. Since there is no open source code of the game, a game clone has been developed independently of our algorithm. This implementation can be used to support experiments with procedural content generation (PCG) methods for this game type. We performed experiments in order to evaluate the expressivity of the level generator and the results showed that the proposed algorithm could generate levels with interesting stable structures.
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Increased prevalence of obesity is associated with the growth of chronic degenerative diseases. One of the main factors associated with this increase is the change in nutritional status of individuals. Medium chain triglycerides (MCT) are rapidly metabolized and less stored in the adipose tissue, being a possible tool for weight control. In order to analyze the influence of consumption of this lipid on satiety, body composition and energy expenditure (EE), a literature review was performed of controlled clinical studies reported in PUBMED and ELSEVIER between the years 2000 and 2010. Fourteen articles were selected presenting short and long-term intervention. Among these, six showed a decrease in body mass of individuals, with consequent loss of weight. Only one showed a positive effect on satiation and four showed an increase in EE. Thus the results are inconclusive and there is a need for further controlled studies with standardized amounts of MCT, so that its use can become an alternative for obesity nutritional treatment.
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Objective: Funnel plots (plots of effect estimates against sample size) may be useful to detect bias in meta-analyses that were later contradicted by large trials. We examined whether a simple test of asymmetry of funnel plots predicts discordance of results when meta-analyses are compared to large trials, and we assessed the prevalence of bias in published meta-analyses. Design: Medline search to identify pairs consisting of a meta-analysis and a single large trial (concordance of results was assumed if effects were in the same direction and the meta-analytic estimate was within 30
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The CONSORT statement is used worldwide to improve the reporting of randomised controlled trials. Kenneth Schulz and colleagues describe the latest version, CONSORT 2010, which updates the reporting guideline based on new methodological evidence and accumulating experience. To encourage dissemination of the CONSORT 2010 Statement, this article is freely accessible on bmj.com and will also be published in the Lancet, Obstetrics and Gynecology, PLoS Medicine, Annals of Internal Medicine, Open Medicine, Journal of Clinical Epidemiology, BMC Medicine, and Trials.
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Medium-chain triacylglycerols (MCT), omega-3 polyunsaturated fatty acids (n-3-PUFA) and micronutrients may be useful for weight and cardiometabolic risk management. However, studies analyzing the effect of a combination of both in individuals at increased cardiometabolic risk are lacking. Therefore, this randomized, controlled, double-blind study investigated the effect of a fat spread enriched with two different doses of MCT and a special long-chain fatty acid-micronutrient combination on cardiometabolic risk factors in overweight diabetic patients. Fifty-four patients received either a fat spread with 6 g/d MCT (MCT30%) or 1.2 g/d (MCT6%). Forty-three completed the study. Analysis was performed according to the median of MCT intake (supplemented and food-derived MCT). Clinical, anthropometric, blood, 24 h-urine parameters and dietary intake were assessed at baseline and after 12 weeks. Total MCT intake > 7 g/d (MCT > 7 group) significantly reduced waist circumference (WC) by 1.81 ± 2.69 cm, whereas ≤ 7 g/d MCT (MCT ≤ 7 group) increased WC by 0.32 ± 3.03 cm (p = 0.027), which was supported by a change in waist-to-height ratio (WHtR) (p = 0.018). Fasting serum triglycerides (TG) increased in both groups over time due to dietary habits. In contrast, diabetic metabolic situation and urinary albumin excretion did not alter. Urinary pH differed significantly between groups after 12 weeks. An intake of >7 g/d MCT reduced WC in overweight diabetics, whereas the increase in the intake of fatty acids may have worsened fasting TG. Therefore, the suitability of a fat for nutrient enrichment remains to be challenged, and further studies in low-fat matrices are desirable.
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Current dietary recommendations advise reducing the intake of saturated fatty acids (SFAs) to reduce coronary heart disease (CHD) risk, but recent findings question the role of SFAs. This expert panel reviewed the evidence and reached the following conclusions: the evidence from epidemiologic, clinical, and mechanistic studies is consistent in finding that the risk of CHD is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs). In populations who consume a Western diet, the replacement of 1% of energy from SFAs with PUFAs lowers LDL cholesterol and is likely to produce a reduction in CHD incidence of ≥2-3%. No clear benefit of substituting carbohydrates for SFAs has been shown, although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index. Insufficient evidence exists to judge the effect on CHD risk of replacing SFAs with MUFAs. No clear association between SFA intake relative to refined carbohydrates and the risk of insulin resistance and diabetes has been shown. The effect of diet on a single biomarker is insufficient evidence to assess CHD risk. The combination of multiple biomarkers and the use of clinical endpoints could help substantiate the effects on CHD. Furthermore, the effect of particular foods on CHD cannot be predicted solely by their content of total SFAs because individual SFAs may have different cardiovascular effects and major SFA food sources contain other constituents that could influence CHD risk. Research is needed to clarify the role of SFAs compared with specific forms of carbohydrates in CHD risk and to compare specific foods with appropriate alternatives.
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Clinical trial registries are in widespread use to promote transparency around trials and their results. To describe characteristics of drug trials listed in ClinicalTrials.gov and examine whether the funding source of these trials is associated with favorable published outcomes. An observational study of safety and efficacy trials for anticholesteremics, antidepressants, antipsychotics, proton-pump inhibitors, and vasodilators conducted between 2000 and 2006. ClinicalTrials.gov, a Web-based registry of clinical trials launched in 1999. Publications resulting from the trials for the 5 drug categories of interest were identified, and data were abstracted on the trial record and publication, including timing of registration, elements of the study design, funding source, publication date, and study outcomes. Assessments were based on the primary funding categories of industry, government agencies, and nonprofit or nonfederal organizations. Among 546 drug trials, 346 (63%) were primarily funded by industry, 74 (14%) by government sources, and 126 (23%) by nonprofit or nonfederal organizations. Trials funded by industry were more likely to be phase 3 or 4 trials (88.7%; P < 0.001 across groups), to use an active comparator in controlled trials (36.8%; P = 0.010 across groups), to be multicenter (89.0%; P < 0.001 across groups), and to enroll more participants (median sample size, 306 participants; P < 0.001 across groups). Overall, 362 (66.3%) trials had published results. Industry-funded trials reported positive outcomes in 85.4% of publications, compared with 50.0% for government-funded trials and 71.9% for nonprofit or nonfederal organization-funded trials (P < 0.001). Trials funded by nonprofit or nonfederal sources with industry contributions were also more likely to report positive outcomes than those without industry funding (85.0% vs. 61.2%; P = 0.013). Rates of trial publication within 24 months of study completion ranged from 32.4% among industry-funded trials to 56.2% among nonprofit or nonfederal organization-funded trials without industry contributions (P = 0.005 across groups). The publication status of a trial could not always be confirmed, which could result in misclassification. Additional information on study protocols and comprehensive trial results were not available to further explore underlying factors for the association between funding source and outcome reporting. In this sample of registered drug trials, those funded by industry were less likely to be published within 2 years of study completion and were more likely to report positive outcomes than were trials funded by other sources. National Library of Medicine and National Institute of Child Health and Human Development, National Institutes of Health.
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The effects of dietary supplementation with coconut oil on the biochemical and anthropometric profiles of women presenting waist circumferences (WC) >88 cm (abdominal obesity) were investigated. The randomised, double-blind, clinical trial involved 40 women aged 20-40 years. Groups received daily dietary supplements comprising 30 mL of either soy bean oil (group S; n = 20) or coconut oil (group C; n = 20) over a 12-week period, during which all subjects were instructed to follow a balanced hypocaloric diet and to walk for 50 min per day. Data were collected 1 week before (T1) and 1 week after (T2) dietary intervention. Energy intake and amount of carbohydrate ingested by both groups diminished over the trial, whereas the consumption of protein and fibre increased and lipid ingestion remained unchanged. At T1 there were no differences in biochemical or anthropometric characteristics between the groups, whereas at T2 group C presented a higher level of HDL (48.7 +/- 2.4 vs. 45.00 +/- 5.6; P = 0.01) and a lower LDL:HDL ratio (2.41 +/- 0.8 vs. 3.1 +/- 0.8; P = 0.04). Reductions in BMI were observed in both groups at T2 (P < 0.05), but only group C exhibited a reduction in WC (P = 0.005). Group S presented an increase (P < 0.05) in total cholesterol, LDL and LDL:HDL ratio, whilst HDL diminished (P = 0.03). Such alterations were not observed in group C. It appears that dietetic supplementation with coconut oil does not cause dyslipidemia and seems to promote a reduction in abdominal obesity.
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Combination of decreased energy expenditure and increased food intake results in fat accumulation either in the abdominal site (upper body obesity, UBO) or on the hips (lower body obesity, LBO). In this study, we used microarray gene expression profiling of adipose tissue biopsies to investigate the effect of body fat distribution on the physiological response to two dietary fat interventions. Mildly obese UBO and LBO male subjects (n = 12, waist-to-hip ratio range 0.93-1.12) were subjected to consumption of diets containing predominantly either long-chain fatty acids (PUFA) or medium-chain fatty acids (MCT). The results revealed (1) a large variation in transcription response to MCT and PUFA diets between UBO and LBO subjects, (2) higher sensitivity of UBO subjects to MCT/PUFA dietary intervention and (3) the upregulation of immune and apoptotic pathways and downregulation of metabolic pathways (oxidative, lipid, carbohydrate and amino acid metabolism) in UBO subjects when consuming MCT compared with PUFA diet. In conclusion, we report that despite the recommendation of MCT-based diet for improving obesity phenotype, this diet may have adverse effect on inflammatory and metabolic status of UBO subjects. The body fat distribution is, therefore, an important parameter to consider when providing personalized dietary recommendation.
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There has been substantial public debate about the susceptibility of research to biases of various kinds. The dialogue has extended to the peer-reviewed literature, scientific conferences, the mass media, government advisory bodies, and beyond. While biases can come from myriad sources, the overwhelming focus of the discussion, to date, has been on industry-funded science. Given the critical role that industry has played and will continue to play in the research process, the International Life Sciences Institute (ILSI) North America Working Group on Guiding Principles has, in this paper, set out proposed conflict-of-interest guidelines regarding industry funding for protecting the integrity and credibility of the scientific record, particularly with respect to health, nutrition, and food safety science. Eight principles are enumerated, specifying ground rules for industry-sponsored research. The paper, which issues a challenge to the broader scientific community to address all bias issues, is only a first step; the document is intended to be dynamic, prompting ongoing discussion and refinement.
Article
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To investigate the effects of medium- and long-chain triacylglycerol (MLCT) on blood triglyceride (TG) in Chinese hypertriglyceridemic subjects. A double-blind controlled clinical trial was carried out, in which 112 subjects with hypertriglyceridemia were randomly divided into two dietary oil groups: (1) long-chain triacylglycerol (LCT) and (2) MLCT. All subjects were requested to ingest fixed energy and to continue their normal activity levels, and to consume LCT or MLCT oil at 25-30 g daily during the study period. Anthropometric measurements of body weight, body mass index (BMI), body fat, body fat percentage, waist and hip circumference (WC and HC), areas of subcutaneous and visceral fat by computed tomography scanning and blood biochemical markers were measured at the beginning and end of the study. There were 50 and 51 subjects left in LCT and MLCT groups, respectively. There were no significant differences in daily intake of energy, protein, fat and carbohydrate, as well as the daily physical activity between the two groups during the study. After 8 weeks, MLCT group showed a significant decrease in body weight, BMI, WC, HC, ratio of WC and HC, body fat, body fat percentage and subcutaneous fat when compared with the initial values. The decrease in body weight, BMI, WC, body fat and subcutaneous and visceral fat was significantly greater in MLCT group than that in the LCT group. Furthermore, the serum concentrations of TG in MLCT group were significantly lower than those in the LCT group. Consumption of MLCT may reduce body weight, body fat and blood TG in hypertriglyceridemic subjects under an appropriate dietary regime.
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Medium chain triglyceride (MCT) consumption may have a beneficial impact on weight management, however, some studies point to a negative impact of MCT oil consumption on cardiovascular disease risk. This study examined the effects of MCT oil consumption, as part of a weight loss diet, on metabolic risk profile compared to olive oil. Thirty-one men and women, age 19-50 y and body mass index 27-33 kg/m(2), completed this randomized, controlled, 16-week weight loss program. Oils were consumed at a level of approximately 12% of the subjects' prescribed energy intakes in the form of muffins and liquid oil. After controlling for body weight, there was a significant effect of time on fasting serum glucose (P = 0.0177) and total cholesterol (P = 0.0386) concentrations, and on diastolic blood pressure (P = 0.0413), with reductions in these variables occurring over time; there was no time-by-diet interaction for any of the parameters studied. Two of the 3 subjects in the MCT oil group with evidence of the metabolic syndrome at baseline did not have metabolic syndrome at endpoint. In the olive oil group, 6 subjects had the metabolic syndrome at baseline; 2 subjects no longer had metabolic syndrome at endpoint, 1 person developed metabolic syndrome, and 4 subjects did not have any change in their metabolic syndrome status. Our results suggest that MCT oil can be incorporated into a weight loss program without fear of adversely affecting metabolic risk factors. Distinction should be made regarding chain length when it comes to discussing the effects of saturated fats on metabolic risk factors.
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This study assessed fasting plasma lipids and lipoproteins and postprandial plasma lipids in healthy male subjects fed liquid-formula diets containing 40% of total energy as long-chain (LCT, primarily C18:1 and C18:2), medium-chain (MCT, C8:0-C10:0), or mixed-chain (structured lipid, STL, mostly C8:0, C10:0, and C22:0) triglycerides for 6 d. None of the diets altered plasma cholesterol concentrations. HDL cholesterol was decreased 14% by the STL diet (P < 0.044) and 15% by the MCT diet (P < 0.004) but was unchanged by the LCT diet. Plasma triglycerides were elevated 42% by the MCT diet (P < 0.006), but were unaltered by either the STL or LCT diets. Neither the STL nor the MCT diets produced changes in fasting lipoprotein lipid composition; however, during the LCT diet, VLDLs became enriched in triglyceride and LDLs became enriched in cholesterol. Postprandial triglyceridemia was significantly greater after subjects consumed the LCT diet than it was after they consumed either the STL or MCT diets, which were similar. Short-term feeding of MCT and STL diets produces significant changes in lipid metabolism. An understanding of the long-term effects of these diets awaits further study.
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Background: Clinical trial registries are in widespread use to promote transparency around trials and their results. Objective: To describe characteristics of drug trials listed in ClinicalTrials.gov and examine whether the funding source of these trials is associated with favorable published outcomes. Design: An observational study of safety and efficacy trials for anticholesteremics, antidepressants, antipsychotics, proton-pump inhibitors, and vasodilators conducted between 2000 and 2006. Setting: ClinicalTrials.gov, a Web-based registry of clinical trials launched in 1999. Measurements: Publications resulting from the trials for the 5 drug categories of interest were identified, and data were abstracted on the trial record and publication, including timing of registration, elements of the study design, funding source, publication date, and study outcomes. Assessments were based on the primary funding categories of industry, government agencies, and nonprofit or nonfederal organizations. Results: Among 546 drug trials, 346 (63%) were primarily funded by industry, 74 (14%) by government sources, and 126 (23%) by nonprofit or nonfederal organizations. Trials funded by industry were more likely to be phase 3 or 4 trials (88.7%; P < 0.001 across groups), to use an active comparator in controlled trials (36.8%; P = 0.010 across groups), to be multicenter (89.0%; P < 0.001 across groups), and to enroll more participants (median sample size, 306 participants; P < 0.001 across groups). Overall, 362 (66.3%) trials had published results. Industry-funded trials reported positive outcomes in 85.4% of publications, compared with 50.0% for government-funded trials and 71.9% for nonprofit or nonfederal organization-funded trials (P < 0.001). Trials funded by nonprofit or nonfederal sources with industry contributions were also more likely to report positive outcomes than those without industry funding (85.0% vs. 61.2%; P = 0.013). Rates of trial publication within 24 months of study completion ranged from 32.4% among industry-funded trials to 56.2% among nonprofit or nonfederal organization-funded trials without industry contributions (P = 0.005 across groups). Limitations: The publication status of a trial could not always be confirmed, which could result in misclassification. Additional information on study protocols and comprehensive trial results were not available to further explore underlying factors for the association between funding source and outcome reporting. Conclusion: In this sample of registered drug trials, those funded by industry were less likely to be published within 2 years of study completion and were more likely to report positive outcomes than were trials funded by other sources. Primary funding source: National Library of Medicine and National Institute of Child Health and Human Development, National Institutes of Health.
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The use of medium-chain triglycerides (MCTs) has been studied for years in an attempt to elucidate their effects in food intake and body weight in animals. The aim of this study was to determine whether there is evidence that the use of MCT reduces consumption and body weight gain in rats, a species chosen as it has been widely used as an animal model in different surveys. A search of scientific work was performed in November 2011 on two bases: 'Web of Science' and 'PubMed'. The terms sample size and homogeneity, randomisation, food consumption and weight gain, body composition, enzyme activity and hormonal activity in rats were used as selection criteria. Thirteen papers were selected after the refinement of the research. Twelve studies measured weight gain and among these, seven detected a decrease in weight gain and five found no differences. Twelve papers also measured food intake and among these, four detected a decrease in consumption, one detected an increase and seven found no differences. Based on established criteria for the ranking of scientific papers, it is concluded that there is strong evidence that MCTs can effectively reduce the consumption and subsequent weight gain of animals. However, in the long term, there may not be differences in results depending on the phenotypic adaptation of animals to a new metabolic condition.