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Changes in Gut Microbiota-Related Metabolites and Long-term Successful Weight Loss in Response to Weight-Loss Diets: The POUNDS Lost Trial.
Heianza, Y, Sun, D, Smith, SR, Bray, GA, Sacks, FM, Qi, L
Diabetes care. 2018;41(3):413-419
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Evidence has demonstrated that weight loss contributes to lowering the risk of developing type 2 diabetes among obese patients. The aim of this study was to examine whether diet-induced metabolites were associated with improvements in adiposity and metabolism during a weight-loss diet intervention in 510 overweight and obese individuals. Participants were randomly assigned to one of four diets with varying macronutrient composition to adhere to for six months. Blood samples and anthropometric data were taken at baseline and 6 months to monitor changes. This study found that overweight and obese individuals with reduced choline or L-carnitine levels achieved greater improvements of adiposity and energy metabolism. Based on these results, the authors conclude that metabolites are predictive of patient responsiveness to dietary interventions, and suggest further studies evaluate these effects in the pre-diabetic obese population.
Abstract
OBJECTIVE Adiposity and the gut microbiota are both related to the risk of type 2 diabetes. We aimed to comprehensively examine how changes induced by a weight-loss diet intervention in gut microbiota-related metabolites, such as trimethylamine N-oxide (TMAO) and its precursors (choline and l-carnitine), were associated with improvements in adiposity and regional fat deposition. RESEARCH DESIGN AND METHODS This study included 510 overweight and obese individuals who were randomly assigned one of four diets varying in macronutrient intake. We examined associations of 6-month changes in blood metabolites (TMAO, choline, and l-carnitine) with improvements in body weight (BW), waist circumference (WC), body fat composition, fat distribution, and resting energy expenditure (REE). RESULTS Individuals with a greater reduction of choline (P < 0.0001) and l-carnitine (P < 0.01) rather than TMAO showed significant losses of BW and WC at 6 months. The reduction of choline was significantly predictive of decreases in body fat composition, fat distribution, and REE. Results of sensitivity analysis showed that the baseline diabetes risk status, such as the presence of hyperglycemia (31% of the total participants) and fasting glucose levels, did not modify the associations. Early changes in choline and l-carnitine were significantly predictive of weight loss over 2 years (P < 0.05 for all). Individuals with increases in choline or l-carnitine were 2.35-times (95% CI 1.38, 4.00) or 1.77-times (1.06, 2.95) more likely to fail to lose weight (-5% or more loss) at 2 years. CONCLUSIONS Overweight and obese individuals who showed decreases in circulating choline or l-carnitine levels achieved greater improvements of adiposity and energy metabolism by eating a low-calorie weight-loss diet, suggesting that such metabolites are predictive of individuals' response to the treatment. Further investigations are necessary to confirm our findings, particularly in a population with prediabetes that is more representative of the U.S. population with obesity.
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Resistance Training Prevents Muscle Loss Induced by Caloric Restriction in Obese Elderly Individuals: A Systematic Review and Meta-Analysis.
Sardeli, AV, Komatsu, TR, Mori, MA, Gáspari, AF, Chacon-Mikahil, MPT
Nutrients. 2018;10(4)
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Caloric restriction (55% carbohydrate, 15% protein, 30% fat) is associated with increased lifespans and the attenuation of the harmful effects of aging. Furthermore, it has been shown that resistance training increases lean body mass, promotes strength, and attenuates muscle loss and function in elderly people. The aim of the study is to determine the level of lean body mass that can be preserved when resistance training is associated with caloric restriction interventions in elderly obese humans. The study is a meta-analysis, based on data from randomised-controlled trials. The participants were older adults or elderly people with a mean age > 57 year. Results indicate that caloric restriction associated with resistance training prevents 93% lean body mass loss induced by caloric restriction. Authors conclude that caloric restriction with resistance training almost stopped caloric restriction induced lean body mass loss completely.
Abstract
It remains unclear as to what extent resistance training (RT) can attenuate muscle loss during caloric restriction (CR) interventions in humans. The objective here is to address if RT could attenuate muscle loss induced by CR in obese elderly individuals, through summarized effects of previous studies. Databases MEDLINE, Embase and Web of Science were used to perform a systematic search between July and August 2017. Were included in the review randomized clinical trials (RCT) comparing the effects of CR with (CRRT) or without RT on lean body mass (LBM), fat body mass (FBM), and total body mass (BM), measured by dual-energy X-ray absorptiometry, on obese elderly individuals. The six RCTs included in the review applied RT three times per week, for 12 to 24 weeks, and most CR interventions followed diets of 55% carbohydrate, 15% protein, and 30% fat. RT reduced 93.5% of CR-induced LBM loss (0.819 kg [0.364 to 1.273]), with similar reduction in FBM and BM, compared with CR. Furthermore, to address muscle quality, the change in strength/LBM ratio tended to be different (p = 0.07) following CRRT (20.9 ± 23.1%) and CR interventions (−7.5 ± 9.9%). Our conclusion is that CRRT is able to prevent almost 100% of CR-induced muscle loss, while resulting in FBM and BM reductions that do not significantly differ from CR.
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Dietary Patterns in Secondary Prevention of Heart Failure: A Systematic Review.
Dos Reis Padilha, G, Sanches Machado d'Almeida, K, Ronchi Spillere, S, Corrêa Souza, G
Nutrients. 2018;10(7)
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Diet is recognised as an important factor in the prevention of heart failure, however there is no consensus about which dietary protocol is the most effective. This systematic review aims to clarify links between different dietary measures and markers of heart failure. The review included 12 studies of different types (randomised controlled trials, cross-sectional studies and cohort studies), which examined the DASH diet, Mediterranean diet, high protein diet and low carbohydrate diet. The studies examining the DASH diet demonstrated improvements in various measures of cardiac function and may have benefits for secondary prevention of heart failure. The Mediterranean diet was associated with lower levels of inflammation and improved cardiac function in cross-sectional studies only. High protein and low carbohydrate diets also demonstrated positive effects on markers of heart function however, only one study for each was included. The authors conclude that the current science suggests a positive role for diet in relation to prevention of heart failure and call for further RCTs to be conducted to identify which elements of these different diets are impacting on markers of heart failure.
Abstract
BACKGROUND Diet is an important factor in secondary prevention of heart failure (HF) but there is still no consensus as to which dietary model should be adopted by this population. This systematic review aims to clarify the relationship between dietary patterns and secondary prevention in HF. METHODS We searched the Medline, Embase and Cochrane databases for studies with different dietary patterns and outcomes of secondary prevention in HF. No limitation was used in the search. RESULTS 1119 articles were identified, 12 met the inclusion criteria. Studies with Dietary Approaches to Stop Hypertension (DASH), Mediterranean, Hyperproteic and Low-carb diets were found. The DASH pattern showed improvement in cardiac function, functional capacity, blood pressure, oxidative stress and mortality. The Mediterranean diet had a correlation with inflammation, quality of life and cardiac function but just on cross-sectional studies. Regarding the Hyperproteic and Low-carb diets only one study was found with each pattern and both were able to improve functional capacity in patients with HF. CONCLUSIONS DASH pattern may have benefits in the secondary prevention of HF. The Mediterranean diet demonstrated positive correlation with factors of secondary prevention of HF but need more RCTs and cohort studies to confirm these effects. In addition, the Hyperproteic and Low-carb diets, despite the lack of studies, also demonstrated positive effects on the functional capacity in patients with HF.
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Low-carbohydrate diets for type 1 diabetes mellitus: A systematic review.
Turton, JL, Raab, R, Rooney, KB
PloS one. 2018;13(3):e0194987
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Type 1 diabetes is an autoimmune condition that affects the ability to produce insulin, the hormone that regulates blood sugar levels. Patients with Type 1 diabetes manage their condition with daily insulin injections or patches, and the standard dietary advice is to continue to eat a normal diet, and adjust the insulin dose to keep blood sugar under control. This systematic review of 9 studies of varying types, aimed to examine the effects of low-carbohydrate diets on type 1 diabetes management. 8 of the studies reported a change in HbA1c (the blood marker used to assess long-term blood sugar management); 3 of these reported statistically significant reductions. 2 studies reported statistically significant reductions in daily insulin use whilst following a low-carbohydrate diet. The study authors were unable to conclude an overall effect due to the differences in design and methods used in the 9 studies included. They call for more primary research to be conducted.
Abstract
Type 1 diabetes is an autoimmune condition characterised by pancreatic beta cell destruction and absolute insulin deficiency. The strongest predictor of diabetes complications is glycaemic control and achieving HbA1c ≤ 7.0% is the primary management target. However, standard treatment appears to be lacking and adjunctive strategies require consideration. A systematic review was conducted to examine the effect of low-carbohydrate diets on type 1 diabetes management. Four databases were searched from inception until 28 March 2017: MEDLINE; CINAHL; Cochrane Library; and EMBASE. All primary studies containing a methods section (excluding cross-sectional) were included. Reports had to quantitatively measure the effect(s) of a dietary intervention or observed intake over at least two weeks where carbohydrate is below 45% total energy in adults and/or children with type 1 diabetes. The primary outcome was HbA1c and secondary outcomes were severe hypoglycaemia, total daily insulin, BMI, quality of life and mean daily glucose. Seventy-nine full-text articles were assessed for eligibility and nine were included (two randomised controlled trials, four pre-post interventions, two case-series, one case-report). Eight studies reported a mean change in HbA1c with a low-carbohydrate diet. Of these, four reported a non-significant change (P ≥ 0.05) and three reported statistically significant reductions (P < 0.05). Two studies reported severe hypoglycaemia, five reported total insulin, three reported BMI, and one reported blood glucose. Due to the significant heterogeneity of included studies, an overall effect could not be determined. This review presents all available evidence on low-carbohydrate diets for type 1 diabetes and suggests an urgent need for more primary studies.
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Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion: The DIETFITS Randomized Clinical Trial.
Gardner, CD, Trepanowski, JF, Del Gobbo, LC, Hauser, ME, Rigdon, J, Ioannidis, JPA, Desai, M, King, AC
JAMA. 2018;319(7):667-679
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Obesity is a major public health challenge and different dietary strategies are employed to lose weight. This randomised clinical trial of 609 obese adults between the age of 18 and 50 aimed to determine the effects of a healthy low-fat diet in comparison to a healthy low-carbohydrate diet on weight change over a 12 month period. The study also assessed whether 3 genetic markers and blood sugar management affected weight loss in the 2 groups. Participants in the study were offered 22 group sessions of health coaching to support adherence to the programme. 481 participants completed the study. The low-carbohydrate group lost on average 6kg and the low-fat group lost on average 5.4kg. The difference between the 2 groups did not achieve significance for weight loss. There was also no significant genetic or blood sugar management effect in relation to dietary pattern and weight loss. The authors of this study conclude that the results of this study do not help in identifying which dietary type is better for whom in relation to 3 genetic markers and blood sugar management.
Abstract
Importance: Dietary modification remains key to successful weight loss. Yet, no one dietary strategy is consistently superior to others for the general population. Previous research suggests genotype or insulin-glucose dynamics may modify the effects of diets. Objective: To determine the effect of a healthy low-fat (HLF) diet vs a healthy low-carbohydrate (HLC) diet on weight change and if genotype pattern or insulin secretion are related to the dietary effects on weight loss. Design, Setting, and Participants: The Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) randomized clinical trial included 609 adults aged 18 to 50 years without diabetes with a body mass index between 28 and 40. The trial enrollment was from January 29, 2013, through April 14, 2015; the date of final follow-up was May 16, 2016. Participants were randomized to the 12-month HLF or HLC diet. The study also tested whether 3 single-nucleotide polymorphism multilocus genotype responsiveness patterns or insulin secretion (INS-30; blood concentration of insulin 30 minutes after a glucose challenge) were associated with weight loss. Interventions: Health educators delivered the behavior modification intervention to HLF (n = 305) and HLC (n = 304) participants via 22 diet-specific small group sessions administered over 12 months. The sessions focused on ways to achieve the lowest fat or carbohydrate intake that could be maintained long-term and emphasized diet quality. Main Outcomes and Measures: Primary outcome was 12-month weight change and determination of whether there were significant interactions among diet type and genotype pattern, diet and insulin secretion, and diet and weight loss. Results: Among 609 participants randomized (mean age, 40 [SD, 7] years; 57% women; mean body mass index, 33 [SD, 3]; 244 [40%] had a low-fat genotype; 180 [30%] had a low-carbohydrate genotype; mean baseline INS-30, 93 μIU/mL), 481 (79%) completed the trial. In the HLF vs HLC diets, respectively, the mean 12-month macronutrient distributions were 48% vs 30% for carbohydrates, 29% vs 45% for fat, and 21% vs 23% for protein. Weight change at 12 months was -5.3 kg for the HLF diet vs -6.0 kg for the HLC diet (mean between-group difference, 0.7 kg [95% CI, -0.2 to 1.6 kg]). There was no significant diet-genotype pattern interaction (P = .20) or diet-insulin secretion (INS-30) interaction (P = .47) with 12-month weight loss. There were 18 adverse events or serious adverse events that were evenly distributed across the 2 diet groups. Conclusions and Relevance: In this 12-month weight loss diet study, there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss. In the context of these 2 common weight loss diet approaches, neither of the 2 hypothesized predisposing factors was helpful in identifying which diet was better for whom. Trial Registration: clinicaltrials.gov Identifier: NCT01826591.
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Micronutrient Gaps in Three Commercial Weight-Loss Diet Plans.
G Engel, M, J Kern, H, Brenna, JT, H Mitmesser, S
Nutrients. 2018;10(1)
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Globally, around 39% of adults are overweight and 13% obese, and more than one third of American adults are obese. Being overweight or obese is associated with many chronic conditions, such as heart disease, high blood pressure and type 2 diabetes. Weight loss, even at moderate level, can reduce the risk of these obesity-related chronic conditions. Commercial weight-loss diet plans can vary greatly, not only in energy content but also in macronutrient and micronutrient composition. Most plans restrict calories or certain macronutrients, particularly carbohydrate or fat, and in doing so, often overlook micronutrient, i.e. vitamin and mineral, content. Previous studies have shown that many weight-loss plans do not provide adequate amounts of all micronutrients, and in order to reach the reference daily intakes for various vitamins and minerals, dieters would need to increase their calorie intake significantly and often unrealistically. The authors of this paper analysed seven single-day menus of three select commercial diet plans to determine their micronutrient sufficiency. The diet plans included were Eat to Live-Vegan, Aggressive Weight Loss (ETL-VAWL), Fast Metabolism Diet (FMD), and Eat, Drink and Be Healthy (EDH). ETL-VAWL diet provided less than 90% of recommended amounts for B12, B3, D, E, calcium, selenium and zinc. The FMD diet was low in B1, D, E, calcium, magnesium and potassium, while EDH diet didn’t meet the recommended amounts for vitamin D, calcium and potassium. Even after adjusting all the plans to an intake of 2000 kcal/day, several micronutrients were found to remain inadequate (vitamin B12 in ETL-VAWL, calcium in FMD and EDH and vitamin D in all diets). The authors conclude that, in order to reduce the risk of micronutrient deficiencies, more attention needs to be paid to micronutrient rich foods when designing commercial diet plans. Alternatively, these nutrient gaps should be filled in other ways, e.g. using appropriate dietary supplements.
Abstract
Weight-loss diets restrict intakes of energy and macronutrients but overlook micronutrient profiles. Commercial diet plans may provide insufficient micronutrients. We analyzed nutrient profiles of three plans and compared their micronutrient sufficiency to Dietary Reference Intakes (DRIs) for male U.S. adults. Hypocaloric vegan (Eat to Live-Vegan, Aggressive Weight Loss; ETL-VAWL), high-animal-protein low-carbohydrate (Fast Metabolism Diet; FMD) and weight maintenance (Eat, Drink and Be Healthy; EDH) diets were evaluated. Seven single-day menus were sampled per diet (n = 21 menus, 7 menus/diet) and analyzed for 20 micronutrients with the online nutrient tracker CRON-O-Meter. Without adjustment for energy intake, the ETL-VAWL diet failed to provide 90% of recommended amounts for B12, B₃, D, E, calcium, selenium and zinc. The FMD diet was low (<90% DRI) in B₁, D, E, calcium, magnesium and potassium. The EDH diet met >90% DRIs for all but vitamin D, calcium and potassium. Several micronutrients remained inadequate after adjustment to 2000 kcal/day: vitamin B12 in ETL-VAWL, calcium in FMD and EDH and vitamin D in all diets. Consistent with previous work, micronutrient deficits are prevalent in weight-loss diet plans. Special attention to micronutrient rich foods is required to reduce risk of micronutrient deficiency in design of commercial diets.
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Effects of Providing High-Fat versus High-Carbohydrate Meals on Daily and Postprandial Physical Activity and Glucose Patterns: a Randomised Controlled Trial.
Parr, EB, Devlin, BL, Callahan, MJ, Radford, BE, Blankenship, JM, Dunstan, DW, Hawley, JA
Nutrients. 2018;10(5)
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The timing of habitual meal consumption and composition is known to be an important factor in health status, particularly for blood glucose regulation. The aim of this randomised crossover study was to assess the effects of altering meal timing and diet composition on postprandial glucose and physical activity levels. Eight overweight or obese men with a sedentary lifestyle completed two 12-day measurement periods including a 7-day habitual period followed by a 5-day experimental period, with an 8-day washout period. The two conditions tested were a high-fat, low carbohydrate diet (HFD) and a high-carbohydrate, low-fat diet (HCD) and participants were instructed to consume meals at standardised times throughout both conditions. Body composition, oxygen consumption and blood glucose were measured at baseline and between each experimental condition. This trial found the provision of meals did not alter overall activity patterns or postprandial activity patterns. The authors observed increased sedentary activity across the day, and identify evening time as an important target for sedentary time to be minimised. Based on these results, the authors suggest that future dietary interventions consider habitual meal consumption and composition to best replicate real-world behaviours.
Abstract
We determined the effects of altering meal timing and diet composition on temporal glucose homeostasis and physical activity measures. Eight sedentary, overweight/obese men (mean ± SD, age: 36 ± 4 years; BMI: 29.8 ± 1.8 kg/m²) completed two × 12-day (12-d) measurement periods, including a 7-d habitual period, and then 5 d of each diet (high-fat diet [HFD]: 67:15:18% fat:carbohydrate:protein versus high-carbohydrate diet [HCD]: 67:15:18% carbohydrate:fat:protein) of three meals/d at ±30 min of 0800 h, 1230 h, and 1800 h, in a randomised order with an 8-d washout. Energy intake (EI), the timing of meal consumption, blood glucose regulation (continuous glucose monitor system (CGMS)), and activity patterns (accelerometer and inclinometer) were assessed across each 12-d period. Meal provision did not alter the patterns of reduced physical activity, and increased sedentary behaviour following dinner, compared with following breakfast and lunch. The HCD increased peak (+1.6 mmol/L, p < 0.001), mean (+0.5 mmol/L, p = 0.001), and total area under the curve (+670 mmol/L/min, p = 0.001), as well as 3-h postprandial meal glucose concentrations (all p < 0.001) compared with the HFD. In overweight/obese males, the provision of meals did not alter physical activity patterns, but did affect glycaemic control. Greater emphasis on meal timing and composition is required in diet and/or behaviour intervention studies to ensure relevance to real-world behaviours.
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A Pecan-Rich Diet Improves Cardiometabolic Risk Factors in Overweight and Obese Adults: A Randomized Controlled Trial.
McKay, DL, Eliasziw, M, Chen, CYO, Blumberg, JB
Nutrients. 2018;10(3)
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There has been a global rise in cardiovascular disease (CVD) and type 2 diabetes mellitus (TD2M) and dietary risk factors are a known contributor. While evidence has shown that an increased intake of tree nuts is associated with a reduced risk of disease indicators, there is limited research specifically on the effects of pecans. The aim of this randomised crossover trial was to assess the impact of pecan consumption on biomarkers related to CVD and T2DM risk in 26 overweight or obese women. Participants consumed a pecan-rich diet with an iso-caloric control diet of similar fat and fibre content, but absent in nuts, for four weeks with a two-week washout period. This trial demonstrated that displacing a portion of saturated fat in the typical American diet with pecans has a protective effect for CVD and TD2M. Based on these results, the authors recommend using dietary change as a first-line approach to disease prevention and management and suggest further studies be done to better understand potential benefits and associated mechanisms.
Abstract
Evidence from observational and intervention studies has shown a high intake of tree nuts is associated with a reduced risk of cardiovascular disease (CVD), mortality from type 2 diabetes (T2DM), and all-cause mortality. However, there is limited data regarding their effects on indicators of cardiometabolic risk other than hypercholesterolemia, and little is known about the demonstrable health benefits of pecans (Carya illinoensis (Wangenh.) K.Koch). We conducted a randomized, controlled feeding trial to compare the effects of a pecan-rich diet with an isocaloric control diet similar in total fat and fiber content, but absent nuts, on biomarkers related to CVD and T2DM risk in healthy middle-aged and older adults who are overweight or obese with central adiposity. After 4 weeks on a pecan-rich diet, changes in serum insulin, insulin resistance (HOMA-IR) and beta cell function (HOMA-β) were significantly greater than after the control diet (p < 0.05). Pecan consumption also lowered the risk of cardiometabolic disease as indicated by a composite score reflecting changes in clinically relevant markers. Thus, compared to the control diet, the pecan intervention had a concurrent and clinically significant effect on several relevant markers of cardiometabolic risk.
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Randomised trial of coconut oil, olive oil or butter on blood lipids and other cardiovascular risk factors in healthy men and women.
Khaw, KT, Sharp, SJ, Finikarides, L, Afzal, I, Lentjes, M, Luben, R, Forouhi, NG
BMJ open. 2018;8(3):e020167
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Blood lipids is a term used for fatty substances found in the blood such as cholesterol and triglycerides. When these fatty substances are above a normal level it may increase an individual’s risk factors for coronary heart diseases. A diet high in saturated fats is linked to an increased amount of these fats in the blood. Recent renewed interest in the health effects of saturated fats based on their composition (long chain, medium chain, and short chain) brought about this randomised control trial. The aim of the study was to compare the effects of butter, extra virgin coconut oil and olive oil on blood lipids. The study population were men and women aged between 50 and 70 years who did not have any known medical history of heart disease or were on any medication related to heart disease. At the end of the four week trial period, significant changes in the blood lipids were observed within the three intervention groups. The concentration of LDL cholesterol in the butter group when compared with coconut oil and olive oil showed a significant increase, whilst no difference was observed in the LDL cholesterol concentration between the olive oil and coconut oil group. The concentration of HDL cholesterol in the coconut oil group increased significantly in comparison to the butter or olive oil group. However, the authors concluded that as further trials between different fatty acids and health are required, the current recommendation of the American Heart Association - to reduce saturated fat in general - is strongly recommended.
Abstract
INTRODUCTION High dietary saturated fat intake is associated with higher blood concentrations of low-density lipoprotein cholesterol (LDL-C), an established risk factor for coronary heart disease. However, there is increasing interest in whether various dietary oils or fats with different fatty acid profiles such as extra virgin coconut oil may have different metabolic effects but trials have reported inconsistent results. We aimed to compare changes in blood lipid profile, weight, fat distribution and metabolic markers after four weeks consumption of 50 g daily of one of three different dietary fats, extra virgin coconut oil, butter or extra virgin olive oil, in healthy men and women in the general population. DESIGN Randomised clinical trial conducted over June and July 2017. SETTING General community in Cambridgeshire, UK. PARTICIPANTS Volunteer adults were recruited by the British Broadcasting Corporation through their websites. Eligibility criteria were men and women aged 50-75 years, with no known history of cancer, cardiovascular disease or diabetes, not on lipid lowering medication, no contraindications to a high-fat diet and willingness to be randomised to consume one of the three dietary fats for 4 weeks. Of 160 individuals initially expressing an interest and assessed for eligibility, 96 were randomised to one of three interventions; 2 individuals subsequently withdrew and 94 men and women attended a baseline assessment. Their mean age was 60 years, 67% were women and 98% were European Caucasian. Of these, 91 men and women attended a follow-up assessment 4 weeks later. INTERVENTION Participants were randomised to extra virgin coconut oil, extra virgin olive oil or unsalted butter and asked to consume 50 g daily of one of these fats for 4 weeks, which they could incorporate into their usual diet or consume as a supplement. MAIN OUTCOMES AND MEASURES The primary outcome was change in serum LDL-C; secondary outcomes were change in total and high-density lipoprotein cholesterol (TC and HDL-C), TC/HDL-C ratio and non-HDL-C; change in weight, body mass index (BMI), waist circumference, per cent body fat, systolic and diastolic blood pressure, fasting plasma glucose and C reactive protein. RESULTS LDL-C concentrations were significantly increased on butter compared with coconut oil (+0.42, 95% CI 0.19 to 0.65 mmol/L, P<0.0001) and with olive oil (+0.38, 95% CI 0.16 to 0.60 mmol/L, P<0.0001), with no differences in change of LDL-C in coconut oil compared with olive oil (-0.04, 95% CI -0.27 to 0.19 mmol/L, P=0.74). Coconut oil significantly increased HDL-C compared with butter (+0.18, 95% CI 0.06 to 0.30 mmol/L) or olive oil (+0.16, 95% CI 0.03 to 0.28 mmol/L). Butter significantly increased TC/HDL-C ratio and non-HDL-C compared with coconut oil but coconut oil did not significantly differ from olive oil for TC/HDL-C and non-HDL-C. There were no significant differences in changes in weight, BMI, central adiposity, fasting blood glucose, systolic or diastolic blood pressure among any of the three intervention groups. CONCLUSIONS AND RELEVANCE Two different dietary fats (butter and coconut oil) which are predominantly saturated fats, appear to have different effects on blood lipids compared with olive oil, a predominantly monounsaturated fat with coconut oil more comparable to olive oil with respect to LDL-C. The effects of different dietary fats on lipid profiles, metabolic markers and health outcomes may vary not just according to the general classification of their main component fatty acids as saturated or unsaturated but possibly according to different profiles in individual fatty acids, processing methods as well as the foods in which they are consumed or dietary patterns. These findings do not alter current dietary recommendations to reduce saturated fat intake in general but highlight the need for further elucidation of the more nuanced relationships between different dietary fats and health. TRIAL REGISTRATION NUMBER NCT03105947; Results.
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Time and Intervention Effects of Daily Almond Intake on the Changes of Lipid Profile and Body Composition Among Free-Living Healthy Adults.
Liu, Y, Hwang, HJ, Kim, HS, Park, H
Journal of medicinal food. 2018;21(4):340-347
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Existing evidence shows that tree nut intake may reduce risk factors associated cardiovascular diseases. While studies have demonstrated this with almond consumption, the mechanism remains uncertain. The aim of this randomised controlled trial was to evaluate the effects of daily almond consumption on changes in body composition and lipid profiles at four different measurement points to provide further mechanistic insight. Eighty-five participants were randomised to either almond or control group and those in the almond group consumed 56g of almonds per day for 20 weeks. Anthropometric and bioimpedance measures were taken, as well as blood lipid profiles, at weeks 0, 8, 16 and 20. This study revealed patterns in blood lipid profiles fluctuations throughout the 20 weeks by utilising four time points. Continuous almond consumption led to significantly greater reductions in blood lipid levels compared to the control group, demonstrating the cardioprotective effects of almonds.
Abstract
Favorable health benefits of almond have been shown in several previous studies. However, repeated measures, randomized, controlled trials to investigate the changes due to almond intake based on the time effects have not yet been reported. The current study was conducted to evaluate the effects of daily almond intake on changes in body composition and lipid profiles for 20 weeks with four measurements among healthy adults. Participants in the almond group showed favorable changes on blood lipid profiles, including levels of triglycerides (TG), total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), and non-high-density lipoprotein (non-HDL-C) after consuming 56 g of almond per day for 20 weeks compared with those at baseline. At week 20, subjects in the almond group showed significantly decreased TC, LDL-C, non-HDL-C, TG, body fat mass, and waist-hip ratio compared with those of the control group who consumed isocaloric control food. The mixed model also confirmed that there were significant time effects in several bioimpedance indicators (i.e., total body protein, fat-free mass, etc.) and all of the lipid profile parameters in the almond group. These results confirm the effects of lipid-lowering and modifying body composition of almond consumption. In addition, our results suggest that the measuring time points would be critical to capture the effects of dietary intervention.