Low-fat Weight-loss Diet Research Articles

DNA Methylation of Birthweight-Blood Pressure Genes and Changes of Blood Pressure in Response to Weight-Loss Diets in the POUNDS Lost Trial.

DNA methylation (DNAm) may play a critical role in bridging prenatal adverse events and cardiometabolic disorders including hypertension in later life. We included 672 adult participants with overweight or obesity, who participated in a 2-year randomized weight-loss dietary intervention study. We defined the regional DNAm levels as the average methylation level of 5'-cytosine-phosphate-guanine-3' within 500 bp of LINC00319 (cg01820192), ATP2B1 (cg00508575), and LMNA (cg12593793), respectively. Generalized linear regression models were used to assess the association between the regional DNAm and 2-year blood pressure changes. Trajectory analysis was used to identify subgroups that shared a similar underlying trajectory of 2-year blood pressure changes. The regional DNAm at LINC00319, showed significantly different associations with 2-year changes in systolic blood pressure and diastolic blood pressure among participants assigned to low- or high-fat diets (P for interaction<0.05 for all). In response to the low-fat diet, per SD higher regional DNAm at LINC00319 was associated with greater reductions in both 2-year changes in systolic blood pressure (β, -1.481; P=0.020) and diastolic blood pressure (β, -1.096; P=0.009). Three trajectories of changes in systolic blood pressure or diastolic blood pressure were identified, and participants with higher regional DNAm at LINC00319 were more likely to experience and maintain decreased systolic blood pressure and diastolic blood pressure (odds ratio of being in decrease-stable versus stable [95% CI], 1.542 [1.146-2.076] and 1.463 [1.125-1.902]). Our findings suggest that DNAm could be a metabolic memory bridging early and later life, and an indicator of more benefits from eating a low-fat weight-loss diet.

Abstract 56: DNA Methylation of Birthweight-Blood Pressure Genes and Changes of Blood Pressures in Response to Weight-Loss Diets

Introduction: DNA methylation (DNAm) may play a critical role in bridging prenatal adverse events and cardiometabolic disorders including hypertension in later life. Hypothesis: DNAm levels of genes related to both birthweight and blood pressure were associated with changes in blood pressures in response to dietary weight-loss interventions. Methods: We included 672 adult participants with overweight or obesity, who participated in a 2-year randomized weight-loss dietary intervention study. Baseline blood DNAm levels were profiled by high-resolution methylC-capture sequencing. We defined the regional DNAm levels as the average methylation level within 500 bp of LINC00319 (cg01820192), ATP2B1 (cg00508575), and LMNA (cg12593793). Generalized linear regression models were used to assess the association between the regional DNAm and 2-year blood pressure changes. Trajectory analysis was used to identify subgroups that shared a similar underlying trajectory of 2-year blood pressure changes. Results: We found that the regional DNAm at LINC00319, but not the other genes, showed different associations with 2-year changes in systolic blood pressure (SBP) and diastolic blood pressure (DBP) among participants assigned low- or high-fat diets (P for interaction &lt; 0.05 for all, Figure ). In response to low-fat diet, per standard deviation higher regional DNAm at LINC00319 was associated with greater reductions in both 2-year changes in SBP (β: -1.481; standard error [SE]: 0.632; P = 0.020) and DBP (β: -1.096; SE: 0.413; P = 0.009). Three trajectories of changes in SBP and DBP were identified, and participants with higher baseline regional DNAm at LINC00319 were less likely to have stable or increased blood pressure levels. Conclusions: Our findings indicate that higher regional DNAm level at LINC00319 was significantly associated with greater long-term reduction in blood pressure in response to a low-fat diet, suggesting people with higher regional DNAm levels benefited more from eating a low-fat weight-loss diet.

The Effect of a Peanut-Enriched Weight Loss Diet Compared to a Low-Fat Weight Loss Diet on Body Weight, Blood Pressure, and Glycemic Control: A Randomized Controlled Trial.

The objective of this study was to examine the effect of consuming 35 g of peanuts prior to two main meals per day as part of a weight loss diet, compared to a traditional low-fat weight loss diet, on body weight, markers of glycemic control, and blood pressure in adults at risk of type 2 diabetes over 6 months. A two-arm randomized controlled trial was conducted. Adults (age > 18 years) with a BMI of >26 kg/m2 at risk of type 2 diabetes were randomized to the peanut group or the traditional low-fat-diet group (control). The peanut group was advised to consume 35 g of lightly salted dry-roasted peanuts prior to two main meals per day. Participants in the control group were given education to follow a low-fat diet. Both groups had dietetic counseling to restrict energy intake (women: <5500 kJ/1300 kcal/d; men: <7000 kJ/1700 kcal/d). Outcome assessment occurred at baseline, 3 months, and 6 months. In total, 107 participants were randomized (65% female; mean age 58 ± 14 years, BMI 33 ± 5.4 kg/m2, waist circumference 109 ± 13 cm, AUSDRISK score 15 ± 5 points), and 76 participants completed the study. No between-group difference in body weight (primary outcome) was observed at 6 months (mean difference, −0.12 kg; 95% CI, −2.42, 2.18; p = 0.92). The mean weight loss at 6 months was 6.7 ± 5.1 kg in the cohort (visit p < 0.001). HbA1c, fasting glucose, fasting insulin, 2-h glucose, and HOMA-IR were not different between the groups. Systolic blood pressure was reduced to a greater extent in the peanut group vs. the control group at 6 months (−5.33 mmHg; 95% CI, −9.23, −1.43; p = 0.008). Intake of 35 g of peanuts prior to two main meals per day, in the context of an energy-restricted diet, resulted in weight loss comparable to a traditional low-fat weight loss diet without preloads. Greater systolic blood pressure reductions were observed with peanut intake, which may lower cardiovascular disease risk.

A Randomized Clinical Trial to Compare a Precision Nutrition Intervention Targeting a Reduction in Postprandial Glycemic Response to Meals With a Low-Fat Diet for Weight Loss

ObjectivesThe primary aim is to compare the effects of a low-fat diet vs a personalized diet on % weight loss at 6-months. Secondary outcomes include body composition (fat mass [FM] and fat free mass [FFM]), resting energy expenditure (REE) and adaptive thermogenesis (AT).MethodsThe Personal Diet Study was a 6-month, single-center, randomized clinical trial in adults with pre-diabetes and moderately controlled type 2 diabetes who were overweight or obese. Participants were randomized to follow either a hypocaloric low-fat diet, with < 25% energy intake from total fat (Standardized), or a hypocaloric personalized diet determined by a machine learning algorithm which predicts PPGR to meals (Personalized). Participants in both arms received behavioral counseling and logged dietary intake and physical activity into a smartphone app. Participants in the Personalized arm received real-time feedback as color-coded scores based on pre-consumed meals entered into the smartphone app. T-tests were used to assess group differences.ResultsA total of 200 adults (Standardized: n = 97 vs. Personalized: n = 103) contributed data (mean [SD]: age, 58 [11] years; 67% female; BMI, 34.0 [4.8] kg/m2; HbA1c, 5.8 [0.6]%; Metformin use, 21.0%). There were no significant group differences in mean % weight loss (Standardized: −4.4 [4.8]% vs Personalized: −3.3 [5.4]%; p = 0.19), mean absolute change in FM (Standardized: −2.7 [3.4] kg vs. Personalized: −1.6 [3.5] kg; p = 0.18), and AT between the two arms (Standardized: −54.7 [177] kcal/d vs. Personalized: 26.2 [199] kcal/d; p = 0.078). However, the Standardized arm lost significantly more FFM (−1.4 [1.6] kg vs. −0.45 [2.0] kg; p = 0.03) and had a greater decrease in REE (−111.0 [195.0] kcal/d vs. 1.93 [215.0] kcal/d; p = 0.02) compared to Personalized.ConclusionsA personalized diet to minimize PPGR had no greater effect on % weight loss compared to a low-fat diet at 6-months. Future precision nutrition trials may require deeper phenotyping of individuals or the development of body weight-specific algorithms.Funding SourcesSupported by grants from the American Heart Association 17SFRN33590133.

349-OR: ADA President's Select Abstract: Circulating Level of DNA Methylation Near CPT1A and Long-Term Changes in Triglycerides in Response to Diet Interventions: The POUNDS Lost Trial

Background: Epigenome-wide association studies identified DNA methylation (DNAm) at several CpG sites of the carnitine palmitoyltransferase-1A (CPT1A) gene to be associated with triglycerides (TG) . However, little is known about whether the pre-treatment DNAm level at CPT1A is associated with changes in TG in response to weight-loss diet interventions. Methods: We included 673 white participants with overweight or obesity, who were randomly assigned to 1 of 4 diets varying in macronutrients components. Blood DNAm levels were profiled by a high-resolution methyl-capture sequencing at baseline. We defined the regional DNAm at CPT1A as the average methylation level over CpGs within 500 bp of the 3 TG-related DNAm sites (cg00574958, cg09737197, and cg17058475) , which were closely located. Two-year changes in TG were calculated. Linear regression models were used to examine the associations between baseline DNAm at CPT1A and 2-year changes in TG. Results: Higher regional DNAm level at CPT1A was associated with lower TG at baseline (β=-2.21, SE=1.01, p=0.029) . We found that dietary fat intake significantly modified the association between baseline DNAm at CPT1A and 2-year changes in TG, independent of concurrent weight-loss (p-int=0.018) . In the low-fat diet group, a higher regional DNAm level was associated with a greater reduction in TG at 2 years, after adjustment for age, sex, baseline body mass index, use of lipid-lowering medication, baseline TG level, and concurrent weight-loss (p=0.01) , whereas no such association was observed in the high-fat diet group (p=0.64) . A similar interaction pattern was also found between dietary fat and baseline DNAm at CPT1A on 2-year changes of TG in very-low-density lipoprotein without apolipoprotein C-III (p-int=0.01) . Conclusion: Our data indicate that participants with a higher regional DNAm level at CPT1A benefited more in long-term improvement in TG when assigned a low-fat weight-loss diet. Disclosure X.Li: None. X.Shao: None. Q.Xue: None. E.Grundberg: None. G.Bray: None. F.Sacks: None. L.Qi: None. Funding The study was supported by grants from the National Heart, Lung, and Blood Institute (HL071981, HL034594, HL126024) , the National Institute of Diabetes and Digestive and Kidney Diseases (DK115679, DK091718, DK100383) , the Fogarty International Center (TW010790) , and Tulane Research Centers of Excellence Awards. Xiang Li was the recipient of the American Heart Association Predoctoral Fellowship Award (19PRE34380036) .

Abstract P126: Identifying Successful Predictors Of Body Fat Reduction In The Dietfits Trial

Background: Reducing excess body fat is important for overall health, but individual success at reducing body fat varies considerably. Because dietary modification plays a key role in reducing body fat and maintaining a healthy body weight, there has been speculation if one particular dietary pattern is superior to another for losing weight. Previously we reported no significant differences in the effectiveness of either a low-carbohydrate diet or a low-fat diet for weight loss in the DIETFITs Trial. However, there is less literature that has specifically focused on body fat reduction. Therefore the purpose of this study was to assess if 12-month dietary changes were associated with body fat reduction. Methods: Participants were men and women with overweight or obesity that participated in the DIETFITS trial, a randomized clinical trial comparing the effectiveness of a healthy low-fat diet to a healthy low-carbohydrate diet for weight loss. The primary outcome was body fat percent loss, which was measured with dual-energy x-ray absorptiometry (DEXA) scans. Demographic information was collected from online surveys at baseline, dietary data were assessed from participants 24-hour recalls, and physical activity was assessed with the Stanford Seven-Day Physical Activity Recall questionnaire. Linear regression models were conducted to assess the association between changes in energy intake, dietary fat, and carbohydrates with body fat reduction, while controlling for demographic variables and physical activity. Results: Data were available for 272 participants with DEXA scans and dietary data. In the main model both baseline physical activity (coef = -0.26, p = 0.016) and changes in physical activity (coef = -0.36, p &lt; 0.01) were significantly associated with body fat reduction. When stratified by dietary assignment, changes in physical activity remained significant for each group (low-carb group: coef = -0.30, p = 0.002 and low-fat group coef = -0.35, p = 0.006), while changes in dietary fat, as a percentage of energy intake, was associated with body fat reduction in the low-fat group only (coef = 0.15, p = 0.006). Race was also significantly associated with body fat reduction in all models, indicating non-White participants gained more body fat at the end of the intervention compared to Whites. Conclusions: The reduction in body fat appears to be mostly driven from participants increasing their physical activity levels. Identifying other predictors of body fat reduction warrant further study.

Is a Biomarker Microvascular Model for Dilation?

Does low-fat diet for weight loss make the impaired microvascular dilation improved through switching to nitric oxide (NO)-dependent in obese adults? The answer is yes. Shane Phillips research group has tested this hypothesis through their most recent publication [1]. While systemic NO doesn’t change, localized NO was increased after a six-week low-fat diet for weight loss (~25% calorie deficit) but not for weight maintenance to obsess subjects with body mass index (BMI most subjects in 30-35, and only a few in 35-40 kg/m2) through increasing flow-induced dilation of arterioles. These in vitro microvascular model data are consistent with data with clinical increase of flow-mediated dilation and decrease of BMI in post- compared to pre-low-fat diet for weight loss

Comparing the Efficacy of Ketogenic Diet with Low-Fat Diet for Weight Loss in Obesity Patients: Evidenc-Based Case Report

Introduction Obesity is a nutritional disease which is still a health burden particularly in Jakarta. The main treatment for obesity is nutritional intervention. Nowadays, several dietary approaches have been developed, including ketogenic diet, which is still controversial. Methods Literature search had been done within 4 databases including PubMed®, Cochrane®, Google® Scholar, and Science Direct®, using keywords: obesity, ketogenic diet, low-fat diet, and weight loss. Then, Medical Sub Heading (MeSH) was used. The search resulted in two articles which were appraised according to aspects of validity, importance, and applicability Results A randomized-controlled trial study showed similar effect of weight loss with ketogenic diet compared to low-fat diet. On the other hand, a meta-analysis study showed ketogenic diet caused more weight loss than low-fat diet. Both studies showed an increased risk of cardiovascular disease from the ketogenic diet group, which were shown by a decrease of flow-mediated dilatation and an increase of LDL-C. Conclusion Ketogenic diet shows a better long-term effect for weight loss in obese patients than low-fat diet. However, ketogenic diet may increase the cardiovascular event risk significantly.

Comparing the Efficacy of Ketogenic Diet with Low-Fat Diet for Weight Loss in Obesity Patients: Evidenc-Based Case Report

Introduction Obesity is a nutritional disease which is still a health burden particularly in Jakarta. The main treatment for obesity is nutritional intervention. Nowadays, several dietary approaches have been developed, including ketogenic diet, which is still controversial. Methods Literature search had been done within 4 databases including PubMed®, Cochrane®, Google® Scholar, and Science Direct®, using keywords: obesity, ketogenic diet, low-fat diet, and weight loss. Then, Medical Sub Heading (MeSH) was used. The search resulted in two articles which were appraised according to aspects of validity, importance, and applicability Results A randomized-controlled trial study showed similar effect of weight loss with ketogenic diet compared to low-fat diet. On the other hand, a meta-analysis study showed ketogenic diet caused more weight loss than low-fat diet. Both studies showed an increased risk of cardiovascular disease from the ketogenic diet group, which were shown by a decrease of flow-mediated dilatation and an increase of LDL-C. Conclusion Ketogenic diet shows a better long-term effect for weight loss in obese patients than low-fat diet. However, ketogenic diet may increase the cardiovascular event risk significantly.

Reductions in food cravings are similar with low-fat weight loss diets differing in protein and carbohydrate in overweight and obese adults with type 2 diabetes: A randomized clinical trial

Food cravings are common in type 2 diabetes (T2D). Higher-protein diets are effective in improving satiety but their effect on cravings is unclear. It was hypothesized that a high protein (HP) diet would provide greater reductions in cravings than an isocaloric higher-carbohydrate diet (HC). In a randomized controlled trial, 61 adults (54% males) with T2D (means ± SD: BMI 34.3 ± 5.1 kg/m2; aged 55 ± 8 years) consumed either a HP diet (mean across study: 29% protein, 34% carbohydrate, 31% fat) or an isocaloric HC diet (21%:48%:24%) for 12-weeks each of weight loss (WL) and weight maintenance (WM). The Food Craving Inventory (FCI), measuring types of foods craved and the General Food Craving Questionnaires measuring traits (G-FCQ-T) and states (G-FCQ-S) were assessed at Weeks 0, 12 and 24. Weight changes were similar between groups (means ± SEM: WL: -7.8 ± 0.6 kg, WM: −0.6 ± 0.4 kg). No group effects or group x time interactions were found for any outcome (P ≥ .07). Independent of group, all food cravings (except carbohydrates) and G-FCQ-T subscales decreased over the 24-week study (P ≤ .04) with sweets and fast food cravings, loss of control and emotional cravings reducing following WL (P ≤ .03). Obsessive preoccupation with food decreased following both phases (WL: P = .03; WM: P = .001). Weight was associated with several FCI subscales (r ≥ 0.24, P ≤ .04). In conclusion, both the HP and HC diets provided significant reductions in food cravings after similar weight losses which were maintained when weight was stabilized.

Effect of a 6-month vegan low-carbohydrate (‘Eco-Atkins’) diet on cardiovascular risk factors and body weight in hyperlipidaemic adults: a randomised controlled trial

ObjectiveLow-carbohydrate diets may be useful for weight loss. Diets high in vegetable proteins and oils may reduce the risk of coronary heart disease. The main objective was to determine the...

The low-carbohydrate diet and cardiovascular risk factors: Evidence from epidemiologic studies

AimsObesity is an important public health issue because of its high prevalence and concomitant increase in risk of cardiovascular diseases. Low carbohydrate diets are popular for weight loss and weight management but are not recommended in leading guidelines due to the perception that increases in dietary fat intake may lead to an adverse cardiovascular risk profile. To clarify the effects of a low-carbohydrate diet for weight loss on cardiovascular disease risk factors as compared to a low fat diet for weight loss, we systematically reviewed data from randomized controlled clinical trials and large observational studies. Data synthesisWe searched the MEDLINE database (Jan 1966–Nov 2013) to identify studies that examined a low-carbohydrate diet as compared to a low-fat diet for weight loss or the improvement of cardiovascular disease risk factors. ConclusionsRecent randomized controlled trials document that low-carbohydrate diets not only decrease body weight but also improve cardiovascular risk factors. In light of this evidence from randomized controlled trials, dietary guidelines should be re-visited advocating a healthy low carbohydrate dietary pattern as an alternative dietary strategy for the prevention of obesity and cardiovascular disease risk factors.

Abstract 18552: Six Months of a Low-Carbohydrate versus Low-Fat Weight Loss Diet Plus Exercise: Effects on Resting and Postprandial Endothelial Function

Background: A worry about low-carbohydrate (CHO) diets is that higher fat meals may adversely affect vascular function acutely, and the regular eating of such meals may lead to chronic vascular impairment. We hypothesized that the effects of a low-CHO vs. low-fat weight loss diet, each combined with exercise training for 6-months, would have similar effects on resting and postprandial endothelial function. Methods: Persons (n=77), BMI 25-42 kg/m2, 30-65 years, were randomly assigned to a low-CHO or low-fat diet, plus exercise. At 0 and 6 months, reactive hyperemia was induced after 5 minutes of upper arm occlusion of SBP. The reactive hyperemia peripheral arterial tonometry index (RH-PAT), a measure of endothelial function, was obtained at rest and 4 hours after eating a McDonald’s breakfast (900 calories, 50 fat grams). We also measured body weight, BMI, and total body fat and trunk fat % by dual-energy X-ray absorptiometry. Results: Sixty subjects (low-CHO group: n=31, 74% female; low-fat group, n=29, 72% female) completed the study. At 0 months, there were no group differences in the following and the combined values are: age, 50.0±8.7 years; weight, 215.4±32.7 lbs; BMI, 34.2±3.8 kg/m2; total body fat, 43.3±7.2%; trunk fat, 46.4±5.7%; RH-PAT, 2.32±0.44%. At 0 months, RH-PAT did not change in response to the meal in either group, overall -0.05±0.64, p=.58. At 6 months, low-CHO vs. low-fat subjects had a greater reduction in weight, -28.9±11.0 vs. -18.7± 2.0 lbs., p&lt;.01; BMI, -4.7±2.0 vs. -2.9±1.7, p&lt;.01; body fat, -6.8±4.5 vs. -4.0±3.9%, p&lt;.02. The groups did not differ in loss of trunk fat, with an overall drop of - 5.5±5.7%, p&lt;.01. At 6 months, there was no change in resting RH-PAT in either group vs. 0 months, overall +0.03±0.53, p=.64 and no group difference in resting vs. postprandial RH-PAT, overall -0.08±0.69, p=.34. Though the 6-month mean resting RH-PAT did not improve, each absolute 1% drop in trunk fat % was associated with an absolute 0.29% (relative 12.5%) increase in RH-PAT, p=.05. Body composition changes did influence postprandial RH-PAT. Conclusions: We found no adverse effects of 6-months of a low-CHO diet on resting or postprandial endothelial function. Central fat loss was associated with improved vascular function, regardless of diet.

Comparison of the effects of 52 weeks weight loss with either a high-protein or high-carbohydrate diet on body composition and cardiometabolic risk factors in overweight and obese males

Background:A high-protein (HP), low-fat weight-loss diet may be advantageous for improving cardiometabolic health outcomes and body composition. To date, only limited research has been conducted in male participants.Objective:To evaluate the medium to long-term effects of two, low-fat, hypocaloric diets differing in carbohydrate:protein ratio on body composition and cardiometabolic health outcomes in overweight and obese males.Design:One hundred and twenty males (age 50.8±9.3 (s.d.) years, body mass index 33.0±3.9 kg m−2) were randomly assigned and consumed a low-fat, isocaloric, energy-restricted diet (7 MJ per day) with either HP (protein:carbohydrate:fat %energy, 35:40:25) or high carbohydrate (HC; 17:58:25). Body weight, body composition and cardiometabolic risk factors were assessed at baseline and after 12 and 52 weeks.Results:Sixty-eight participants completed the study (HP, n=33; HC, n=35). At 1 year both the groups experienced similar reductions in body weight (HP, −12.3±8.0 kg (−12%); HC, −10.9±8.6 kg (−11%); P=0.83 time × group interaction) and fat mass (−9.9±6.0 kg (−27%) vs −7.3±5.8 kg (−22%); P=0.11). Participants who consumed the HP diet lost less fat-free mass (−2.6±3.7 kg (−4%) vs −3.8±4.7 kg (−6%); P<0.01). Both groups experienced similar increases in high-density lipoprotein cholesterol (8%) and reductions in total cholesterol (−7%), low-density lipoprotein cholesterol (−9%), triglycerides (−24%), glucose (−3%), insulin (−38%), blood pressure (−7/−12%) and C-reactive protein (−29%), (P⩾0.14).Conclusion:In overweight and obese men, both a HP and HC diet reduced body weight and improved cardiometabolic risk factors. Consumption of a HP diet was more effective for improving body composition compared with an HC diet.

Comparative effects of low-carbohydrate high-protein versus low-fat diets on the kidney.

Concerns exist about deleterious renal effects of low-carbohydrate high-protein weight loss diets. This issue was addressed in a secondary analysis of a parallel randomized, controlled long-term trial. Between 2003 and 2007, 307 obese adults without serious medical illnesses at three United States academic centers were randomly assigned to a low-carbohydrate high-protein or a low-fat weight-loss diet for 24 months. Main outcomes included renal filtration (GFR) indices (serum creatinine, cystatin C, creatinine clearance); 24-hour urinary volume; albumin; calcium excretion; and serum solutes at 3, 12, and 24 months. Compared with the low-fat diet, low-carbohydrate high-protein consumption was associated with minor reductions in serum creatinine (relative difference, -4.2%) and cystatin C (-8.4%) at 3 months and relative increases in creatinine clearance at 3 (15.8 ml/min) and 12 (20.8 ml/min) months; serum urea at 3 (14.4%), 12 (9.0%), and 24 (8.2%) months; and 24-hour urinary volume at 12 (438 ml) and 24 (268 ml) months. Urinary calcium excretion increased at 3 (36.1%) and 12 (35.7%) months without changes in bone density or clinical presentations of new kidney stones. In healthy obese individuals, a low-carbohydrate high-protein weight-loss diet over 2 years was not associated with noticeably harmful effects on GFR, albuminuria, or fluid and electrolyte balance compared with a low-fat diet. Further follow-up is needed to determine even longer-term effects on kidney function.

A one year high protein, low fat weight loss diet improves body composition and cardiometabolic risk factors in overweight males

ObjectiveTo evaluate the effects of two energy matched, low fat, hypocaloric diets differing in carbohydrate to protein ratio, on body composition and cardiometabolic health outcomes in overweight males.Methods120 males (age 50.8±9.3 yrs, BMI 33.0±3.9 kg/m2) were randomly assigned to a low fat, isocaloric, energy restricted diet (7MJ/day) with either high protein (HP; Pro:Carb:Fat % energy, 35:40:25) or standard protein (SP; 17:58:25). Body weight, body composition, and cardiometabolic risk factors were assessed at baseline and after one year.Results68 participants completed the study (HP n=33; SP n=35). Both groups experienced similar reductions in body weight (HP −12.3±8.0 kg [−12%]; SP −10.9±8.6 kg [−11%]) and fat mass (HP − 9.9±6.0 kg [−27%]; SP −7.3±5.8 kg [−22%]), P&gt;0.11 time x group. Participants who consumed the HP diet lost less fat free mass (−2.6±3.7 kg [−4%] vs. −3.8±4.7 kg [−6%]), P&lt;0.01. Both groups experienced a similar overall increase in HDL cholesterol (8%) and reductions in total cholesterol (−7%), LDL cholesterol (−9%), triglycerides (−24%), glucose (−3%), insulin (−38%), blood pressure (−7/−12%) and C‐reactive protein (−29%), P≥0.14.ConclusionsIn overweight and obese males, a HP and SP diet similarly reduce body weight and improve cardiometabolic health outcomes. A HP diet was more effective for improving body composition.Research support provided by Meat and Livestock Australia.

The Effect of a Plant-Based Low-Carbohydrate (“Eco-Atkins”) Diet on Body Weight and Blood Lipid Concentrations in Hyperlipidemic Subjects

Low-carbohydrate, high-animal protein diets, which are advocated for weight loss, may not promote the desired reduction in low-density lipoprotein cholesterol (LDL-C) concentration. The effect of exchanging the animal proteins and fats for those of vegetable origin has not been tested. Our objective was to determine the effect on weight loss and LDL-C concentration of a low-carbohydrate diet high in vegetable proteins from gluten, soy, nuts, fruits, vegetables, cereals, and vegetable oils compared with a high-carbohydrate diet based on low-fat dairy and whole grain products. A total of 47 overweight hyperlipidemic men and women consumed either (1) a low-carbohydrate (26% of total calories), high-vegetable protein (31% from gluten, soy, nuts, fruit, vegetables, and cereals), and vegetable oil (43%) plant-based diet or (2) a high-carbohydrate lacto-ovo vegetarian diet (58% carbohydrate, 16% protein, and 25% fat) for 4 weeks each in a parallel study design. The study food was provided at 60% of calorie requirements. Of the 47 subjects, 44 (94%) (test, n = 22 [92%]; control, n = 22 [96%]) completed the study. Weight loss was similar for both diets (approximately 4.0 kg). However, reductions in LDL-C concentration and total cholesterol-HDL-C and apolipoprotein B-apolipoprotein AI ratios were greater for the low-carbohydrate compared with the high-carbohydrate diet (-8.1% [P = .002], -8.7% [P = .004], and -9.6% [P = .001], respectively). Reductions in systolic and diastolic blood pressure were also seen (-1.9% [P = .052] and -2.4% [P = .02], respectively). A low-carbohydrate plant-based diet has lipid-lowering advantages over a high-carbohydrate, low-fat weight-loss diet in improving heart disease risk factors not seen with conventional low-fat diets with animal products.

Comparative effects of very low-carbohydrate, high-fat and high-carbohydrate, low-fat weight-loss diets on bowel habit and faecal short-chain fatty acids and bacterial populations

Very low-carbohydrate diets are often used to promote weight loss, but their effects on bowel health and function are largely unknown. We compared the effects of a very low-carbohydrate, high-fat (LC) diet with a high-carbohydrate, high-fibre, low-fat (HC) diet on indices of bowel health and function. In a parallel study design, ninety-one overweight and obese participants (age 50.6 (sd 7.5) years; BMI 33.7 (sd 4.2) kg/m(2)) were randomly assigned to either an energy-restricted (about 6-7 MJ, 30 % deficit) planned isoenergetic LC or HC diet for 8 weeks. At baseline and week 8, 24 h urine and faecal collections were obtained and a bowel function questionnaire was completed. Compared with the HC group, there were significant reductions in the LC group for faecal output (21 (sd 145) v. - 61 (sd 147) g), defecation frequency, faecal excretion and concentrations of butyrate ( - 0.5 (sd 10.4) v. - 3.9 (sd 9.7) mmol/l) and total SCFA (1.4 (sd 40.5) v. - 15.8 (sd 43.6) mmol/l) and counts of bifidobacteria (P < 0.05 time x diet interaction, for all). Urinary phenols and p-cresol excretion decreased (P < or = 0.003 for time) with no difference between diets (P > or = 0.25). Faecal form, pH, ammonia concentration and numbers of coliforms and Escherichia coli did not change with either diet. No differences between the diets were evident for incidences of adverse gastrointestinal symptoms, which suggests that both diets were well tolerated. Under energy-restricted conditions, a short-term LC diet lowered stool weight and had detrimental effects on the concentration and excretion of faecal SCFA compared with an HC diet. This suggests that the long-term consumption of an LC diet may increase the risk of development of gastrointestinal disorders.

Serum Potassium Changes with Initiating Low-Carbohydrate Compared to a Low-Fat Weight Loss Diet in Type 2 Diabetes

To evaluate the change in potassium after initiating a low-carbohydrate or low-fat weight loss diet. Participants randomized to a low-carbohydrate (low-CHO) or a low-fat diet had serum potassium measured at baseline, 3 days, 1 week, 2 weeks, and 1 month after dietary initiation. Paired t tests and repeated measure analysis of variance (ANOVA) compared changes within each subject and between groups. Mean potassium (4.29 mmol/L + 0.41) was similar in both groups at baseline. The low-CHO arm (n = 48) had a mean decrease of 0.16 mmol/L +/- 0.49 (P = 0.03) over one month, and the low-fat arm (n = 47) had a reduction of 0.19 +/- 0.45 (P = 0.006). Serum potassium decreased within 3 days of diet initiation in the low-CHO arm, and at one week in the low-fat arm. Five participants (3 in low-CHO arm) required potassium supplementation for serum potassium <3.5 mmol/L. Minor decreases in potassium occurred after initiating both diets, and was more rapid after the low-CHO diet. These decreases may be clinically meaningful in some patients.

Moderate-carbohydrate low-fat versus low-carbohydrate high-fat meal replacements for weight loss

Objectives To compare the efficacy of a low-carbohydrate high-fat versus a moderate-carbohydrate low-fat diet for weight loss and cardiovascular risk reduction.Methods In a prospective clinical trial, 137 participants (body mass index ≥25 kg/m2) were randomly assigned to Control (46 randomized, 44 completed), Low Carbohydrate (45 randomized, 42 completed), or Moderate Carbohydrate (46 randomized, 40 completed) groups. Outcomes included measures of body size and composition and blood chemistries.Results Both the Low and Moderate Carbohydrate groups lost significantly more weight as well as inches from their waists and thighs than the Control group, while the Low Carbohydrate group lost a greater percentage of body fat. Although the Moderate Carbohydrate group showed significant reductions in serum cholesterol, the Low Carbohydrate group showed the greatest improvements in serum cholesterol, triglycerides, high-density lipoprotein, low-density lipoprotein, and very-low-density lipoprotein.Conclusions Moderate approaches to weight loss such as a moderate-carbohydrate low-fat diet may be prudent.