Dietary Weight Loss Intervention Research Articles

Eating behaviors and weight loss outcomes in a 12-month randomized trial of diet and/or exercise intervention in postmenopausal women

BackgroundCertain eating behaviors are common among women with obesity. Whether these behaviors influence outcomes in weight loss programs, and whether such programs affect eating behaviors, is unclear.MethodsOur aim was to examine the effect of baseline eating behaviors on intervention adherence and weight among postmenopausal women with overweight or obesity, and to assess intervention effects on eating behaviors.Four hundred and 39 women (BMI ≥25 kg/m2) were randomized to 12 months of: i) dietary weight loss with a 10% weight loss goal (‘diet’; n = 118); ii) moderate-to-vigorous intensity aerobic exercise for 225 mins/week (‘exercise’; n = 117); iii) combined dietary weight loss and exercise (‘diet + exercise’; n = 117); or iv) no-lifestyle change control (n = 87). At baseline and 12 months, restrained eating, uncontrolled eating, emotional eating and binge eating were measured by questionnaire; weight and body composition were assessed. The mean change in eating behavior scores and weight between baseline and 12 months in the diet, exercise, and diet + exercise arms were each compared to controls using the generalized estimating equation (GEE) modification of linear regression adjusted for age, baseline BMI, and race/ethnicity.ResultsBaseline restrained eating was positively associated with change in total calories and calories from fat during the dietary intervention but not with other measures of adherence. Higher baseline restrained eating was associated with greater 12-month reductions in weight, waist circumference, body fat and lean mass. Women randomized to dietary intervention had significant reductions in binge eating (− 23.7%, p = 0.005 vs. control), uncontrolled eating (− 24.3%, p < 0.001 vs. control), and emotional eating (− 31.7%, p < 0.001 vs. control) scores, and a significant increase in restrained eating (+ 60.6%, p < 0.001 vs. control); women randomized to diet + exercise reported less uncontrolled eating (− 26.0%, p < 0.001 vs. control) and emotional eating (− 22.0%, p = 0.004 vs. control), and increased restrained eating (+ 41.4%, p < 0.001 vs. control). Women randomized to exercise alone had no significant change in eating behavior scores compared to controls.ConclusionsA dietary weight loss intervention helped women modify eating behaviors. Future research should investigate optimal behavioral weight loss interventions for women with both disordered eating and obesity.Trial registrationNCT00470119 (https://clinicaltrials.gov). Retrospectively registered May 7, 2007.

Weight loss following an intensive dietary weight loss program in obese candidates for bariatric surgery: The retrospective RNPC® cohort

AimBariatric surgery is the most effective treatment for obesity. However, less than 1% of eligible patients undergo bariatric surgery annually. Here we evaluated the weight loss effectiveness of an intensive non-surgical weight loss program in patients that would qualify for bariatric surgery. MethodsPatients eligible for bariatric surgery (n = 1460) (BMI≥40 or BMI≥35 kg/m2 plus comorbidities) who were enrolled in a dietary weight loss intervention, the RNPC® program, were compared to a cohort of bariatric surgery patients in terms of weight loss outcome. ResultsThe 663 patients completing the RNPC® program (35% dropout and 20% ongoing) lost 20.2 ± 11.8 kg corresponding to a reduction of 47% of the excess weight and a percentage weight loss from the initial weight of 18% after a mean period of 18.6 ± 9.1 months. Weight loss 18 months after bariatric surgery (n = 61) was 42.5 ± 15.8 kg corresponding to a reduction of 74% of excess weight and a percentage weight loss from the initial weight of 32%. ConclusionAlthough bariatric surgery results in a more pronounced weight loss, a clinically important weight loss can be obtained in patients that would qualify for bariatric surgery following an intensive non-surgical weight loss program. This retrospective analysis calls for randomized trials that compare the long-term cost-effectiveness between the RNPC® program and bariatric surgery.

1573-P: Branched-Chain Amino Acids, Dietary Protein, and Improvement in Hepatic Fat and Abdominal Fat Distribution in Weight-Loss Diet Intervention: The POUNDS Lost Trial

Background: Recent evidence has related high levels of plasma branch-chained amino acids (BCAAs) with liver and visceral fat. We examined the associations of plasma BCAAs with liver fat and abdominal fat distribution and assessed the potential modification of weight-loss diet interventions on these relations. Methods: The current study included 184 participants with available data on plasma BCAAs, hepatic fat and abdominal fat distribution over 2 years, who were randomly assigned to 1 of 4 diets varying in macronutrient components. Results: Decrease in plasma BCAAs after weight loss was significantly associated with improvement in hepatic density (a marker for hepatic fat; p=0.03) and reduction in visceral fat (p=0.01). We also found that a decrease in BCAAs was associated with decreased insulin, HOMA-IR, and triglycerides (p&amp;lt;0.05 for all). Moreover, we observed significant interactions between total plasma BCAAs and dietary protein on hepatic density (p-interaction=0.01). Individuals with a larger decrease in total BCAAs had a greater increase in hepatic density when consuming a high protein diet. Conclusion: Our findings indicate that weight-loss diets decrease BCAAs, which are in turn associated with the reduction of hepatic and visceral fat. Finally, dietary protein modifies the direction of these associations. Disclosure X. Li: None. D. Sun: None. T. Zhou: None. G. Bray: Advisory Panel; Self; Herbalife International of America, Inc., Medifast. F. Sacks: None. L. Qi: None. Funding National Heart, Lung, and Blood Institute (HL0791981, HL034594, HL126024); National Institute of Diabetes and Digestive and Kidney Diseases (DK115679, DK091718, DK100383, DK078616); Boston Nutrition Obesity Research Center (DK46300); United States-Israel Binational Science Foundation (2011036); American Heart Association (0730094N to L.Q.)

Salivary α-amylase copy number is not associated with weight trajectories and glycemic improvements following clinical weight loss: results from a 2-phase dietary intervention study

Several studies recently reported contradicting results regarding the link between amylase 1 (AMY1) copy numbers (CNs), obesity, and type 2 diabetes. The aim of this study was to assess the impact of AMY1 CN on anthropometrics and glycemic outcomes in obese individuals following a 2-phase dietary weight loss intervention. Using the paralog ratio test, AMY1 CNs were accurately measured in 761 obese individuals from the DiOGenes study. Subjects first underwent an 8-wk low-calorie diet (LCD, at 800 kcal/d) and then were randomly assigned to a 6-mo weight maintenance dietary (WMD) intervention with arms having different glycemic loads. At baseline, a modest association between AMY1 CN and BMI (P=0.04) was observed. AMY1 CN was not associated with baseline glycemic variables. In addition, AMY1 CN was not associated with anthropometric or glycemic outcomes following either LCD or WMD. Interaction analyses between AMY1 CN and nutrient intake did not reveal any significant association with clinical parameters (at baseline and following LCD or WMD) or when testing gene × WMD interactions during the WMD phase. In the absence of association with weight trajectories or glycemic improvements, the AMY1 CN cannot be considered as an important biomarker for response to a clinical weight loss and weight maintenance programs in overweight/obese subjects. This trial was registered at www.clinicaltrials.gov as NCT00390637.

Abstract MP60: Changes in Gut Microbiota Metabolite TMAO Are Related to Changes in Hepatic and Visceral Fat in Weight-loss Diet Interventions: the POUNDS Lost Trial

Objective: Gut microbiota metabolite Trimethylamine-N-oxide (TMAO) has been related to obesity and various cardiometabolic disorders. TMAO is involved in lipid metabolism in the liver; however, little is known about whether changes in TMAO affect hepatic fat and abdominal fat distribution, and whether genetic variations modify such effects. Research Design and Methods: The present study included 92 overweight and obese participants from the POUNDS Lost trial having complete data on computed tomography (CT) scans and a genetic risk score (GRS) for nonalcoholic fatty liver disease (NAFLD). We analyzed the associations of changes in plasma TMAO with changes in hepatic fat and fat distribution from baseline to 6 months; we also assessed the interactions between the GRS and changes in TMAO. Results: Larger decreases in TMAO from baseline were significanly associated with a reduction in subcutaneous adipose tissue (SAT), visceral adipose tissue (VAT), and total adipose tissue (TAT) at 6 months, p=0.01, 0.02, and 0.003, respectively. In addition, we found that larger decreases in TMAO were associated with increases in HDL-cholesterol and decreases in triglycerides, p=0.02 and 0.03, respectively. Moreover, we observed significant interactions between 6-month changes in TMAO and the NAFLD GRS on the concurrent changes in liver fat (P interaction =0.007) and VAT (p interaction =0.018). Among individuals whose TMAO decreased, a lower NAFLD GRS tends to predict a greater improvement in hepatic fat and a reduction in VAT; while in those whose TMAO increased, no differences in hepatic fat or VAT were observed across the tertiles of NAFLD GRS. Conclusions: Our data indicate that changes in TMAO are related to changes in hepatic and visceral fat in weight loss diet interventions; and such relations are modified by genetic variation. Trial Registration: ClinicalTrials.gov NCT00072995.

Abstract P028: Gut Microbiota-Related Metabolites and Long-Term Bone Health in Response to Weight-Loss Diets: The POUNDS Lost Trial

Introduction: Weight-loss diet interventions affect gut microbiota-related metabolites, such as trimethylamine N-oxide (TMAO) and its precursors (choline and L-carnitine), and improve cardiometabolic status. However, little is known about how these metabolites may affect bone mineral density (BMD) during weight loss. Hypothesis: We assessed the hypothesis that changes in gut microbiota-related metabolites are related to changes in BMD during weight loss. Methods: A total of 264 overweight and obese participants with measurement of BMD by dual-energy X-ray (DEXA) scan were included in the present analysis. The participants were randomly assigned to one of four diets varying in macronutrient intakes. We investigated the associations of changes in plasma levels of TMAO, choline, and L-carnitine from baseline to 6 months with changes in BMD. Results and Conclusions: We found that changes in plasma levels of TMAO from baseline to 6 months were positively related to changes of whole body ( P =0.011) and spine ( P =0.002) BMD over the 2-year intervention, independent of weight change. The association with whole body BMD was also significant at 6 months. The correlations between changes in TMAO and BMD were not modified by dietary macronutrients; while changes in TMAO precursor L-carnitine showed interactions with dietary fat intake on changes of spine and trochanter BMD (all P &lt;0.05). Participants with the least L-carnitine decrease showed less BMD reduction by eating a low-fat diet ( P spine =0.031 and P trochanter =0.017). In conclusion, our results suggest that decrease in TMAO during weight loss may be related to reduction in BMD.

Electric stimulation of ears accelerates body weight loss mediated by high-fat to low-fat diet switch accompanied by increased white adipose tissue browning in C57BL/6\u2009J mice

BackgroundWeight reduction frequently occurs in patients receiving vagus nerve stimulation (VNS) therapy. Therefore, we hypothesized that during dietary intervention for weight loss, auricular electric stimulation (AES), an alternative of VNS, accelerates weight loss by increasing white adipose tissue (WAT) browning and increases energy expenditure.MethodsC57BL/6J male mice were fed a high-fat diet for 5 wk. to induce obesity, then switched to a low-fat diet for 5 wk. and allocated into 3 groups to receive 2 Hz electric stimulation on ears, electrode clamps only, or nothing (AES, Sham and Ctrl, respectively).ResultsSwitching to a low-fat diet reduced body weight progressively in all 3 groups, with the greatest reduction in the AES group. In accordance with a mild decrease in feed intake, hypothalamus mRNA levels of Npy, AgRP tended to be reduced, while Pomc tended to be increased by AES. Mice in the AES group had the highest concentrations of norepinephrine in serum and inguinal WAT, and expression levels of uncoupling protein-1 (UCP-1) and tyrosine hydroxylase in inguinal WAT. Furthermore, their subcutaneous adipocytes had multilocular and UCP-1+ characteristics, along with a smaller cell size.ConclusionAES, by increasing WAT browning, could be used in conjunction with a low-fat diet to augment weight loss in addition to suppressing appetite.

Dietary therapy and non-surgical periodontal treatment in obese patients with chronic periodontitis.

The effect of dietary weight loss intervention on periodontal therapy is unknown. Therefore, we aimed to evaluate whether weight loss improves the response of obese subjects to non-surgical periodontal treatment. This interventional study in obese patients was conducted at the University Hospital Dr. Peset (Valencia, Spain). Patients were divided into two groups with and without dietary therapy. All participants received non-surgical periodontal treatment. Periodontal, anthropometric and biochemical parameters were assessed at baseline and 12weeks. A total of 78 patients were re-evaluated after intervention. All periodontal parameters improved in both groups after periodontal treatment, but the reductions in mean probing depth (PD) (0.23mm vs. 0.12mm) and in percentage of sites with PD 4-5mm (10.4% vs. 5.89%) were significantly higher in the dietary group. Additionally, complement component 3 (C3) and tumour necrosis factor alpha (TNFα) decreased in the dietary group after intervention. Percentage of change in mean PD correlated with change in C3 (r=0.233, p=0.043), and percentage of change in sites with PD 4-5mm correlated with change in TNFα (r=0.414, p=0.012). This study suggests that dietary weight loss intervention causes a greater reduction in systemic inflammation, which may enhance the response to periodontal treatment.

Genetically determined vitamin D levels and change in bone density during a weight-loss diet intervention: the Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) Trial

Obesity is closely associated with bone health. Although diet and weight loss produce many metabolic benefits, studies of weight loss diets on bone health are conflicting. Genetic variations, such as vitamin D levels, may partly account for these conflicting observations by regulating bone metabolism. We investigated whether the genetic variation associated with vitamin D concentration affected changes in bone mineral density (BMD) in response to a weight-loss diet intervention. In the 2-y Preventing Overweight Using Novel Dietary Strategies (POUNDS Lost) trial, BMD was measured for 424 participants who were randomly assigned to 1 of 4 diets varying in macronutrient intakes. A genetic risk score (GRS) was calculated based on 3 genetic variants [i.e., 7-dehydrocholesterol reductase (DHCR7) rs12785878, cytochrome P450 2R1 (CYP2R1) rs10741657 and group-specific component globulin (GC) rs2282679] related to circulating vitamin D levels. A dual-energy X-ray absorptiometry scan was performed to assess changes in whole-body BMD over 2 y. The final analysis included 370 participants at baseline. We found a significant interaction between dietary fat intake and vitamin D GRS on 2-y changes in whole-body BMD (P-interaction=0.02). In the high-fat diet group, participants with higher GRS showed significantly less reduction in whole-body BMD than those with lower GRS, whereas the genetic associations were not significant in the low-fat diet group. We also found a significant interaction between dietary fat intake and the GRS on 6-mo change in femur neck BMD (P-interaction=0.02); however, the interaction became nonsignificant at 2 y. Our data indicate that dietary fat intake may modify the effect of vitamin D-related genetic variation on changes in BMD. Overweight or obese patients predisposed to sufficient vitamin D may benefit more in maintaining BMD along with weight loss by eating a low-fat diet. This trial was registered at clinicaltrials.gov as NCT03258203.

Food cravings and body weight: a conditioning response.

To provide current information on interventions that alter food cravings. Specifically, dietary, physical activity, pharmacologic, and bariatric surgery interventions are examined. Lastly, the effects of social determinants and current controversies on food cravings are outlined. Dietary, pharmacologic, and bariatric surgery weight loss interventions decrease food cravings. Physical activity interventions also decrease cravings. There is potential to see differential responses in food cravings in different demographic and socioeconomic groups, but more research is needed. Food cravings influence body weight. Food craving reductions are because of reductions in the frequency of consuming craved foods, independent of energy content, but further research is warranted. Most findings continue to support the conditioning model of food cravings.

An international multi-centre cohort study of weight loss in overweight cats: Differences in outcome in different geographical locations.

IntroductionFeline obesity is a worldwide concern which has recently been formally classified as a disease by the veterinary community. Management involves invoking controlled weight loss by feeding a purpose-formulated food in restricted quantities and altering physical activity. Most weight loss studies conducted in cats have been undertaken in research cat colonies from single geographic locations. The aim of this multi-centre cohort study was to determine the efficacy of a short-term dietary weight loss intervention in overweight pet cats across a range of geographical locations globally.Materials and methodsA 3-month (median 13 weeks, inter-quartile range [IQR] 12–15 weeks) weight loss programme was conducted at 188 veterinary practices in 22 countries, and involving 730 cats, 413 of which completed the programme and had complete data available. All were fed commercially available dry or wet weight loss diets, and median energy intake was 53 kcal/kg BW0.711/day. The Royal Canin Ethics Committee approved the study, and owners gave informed consent. Owners completed behavioural questionnaires assessing begging, physical activity and quality of life (QOL). Linear mixed models were used to assess the respective influence of time, age, and initial body condition score (BCS) on weight loss and behavioural observations.ResultsAt baseline, median age was 72 months (range 12–200 months) and median BCS was 8 (range 7–9). In all, 402/413 cats (97%) lost weight (mean 10.6±6.3%) during the programme at a rate of 0.8 ±0.50%/week. Based upon owner questionnaires, activity and QOL improved (both P<0.001), while begging behaviour decreased (P<0.001) during weight loss. The main factor influencing percentage weight loss was geographical location (P<0.001), with cats in North America losing less weight (median 7.2%, IQR: 4.4–10.4%) than those in both Europe (10.7%, 6-8-15.4%) and South America (10.0%, 6.2–15.4%). Differences in weight loss were also observed amongst countries (P<0.001), with cats in Argentina, Germany, and Italy losing more weight than cats in the USA, and cats in Germany also losing more weight than cats in Portugal.Discussion/conclusionMost of the overweight cats enrolled in this international multi-centre study successfully lost weight. The reason for the differences in percentage weight loss amongst geographical locations requires further study.

Gut Microbiota Metabolites, Amino Acid Metabolites, and Improvements in Diabetes-Related Traits—The POUNDS Lost Trial

Gut microbiota alterations may be related to insulin resistance, diabetes, and the impaired amino acid metabolism. We investigated whether changes in gut microbiota metabolite of trimethylamine N-oxide (TMAO) and its precursors (choline and L-carnitine) were associated with improvements of diabetes-related traits and diabetes-risk-related amino acids in a weight-loss diet intervention. This study included 504 obese adults who were randomly assigned to 1 of 4 energy-reduced diets varying in the macronutrient composition. We calculated changes (Δ) in TMAO, choline, and L-carnitine from baseline to 6 months after the diet intervention. Greater decreases in choline and L-carnitine were significantly (p &amp;lt;0.05) associated with greater improvements in fasting insulin levels and the Homeostatic Model Assessment of Insulin Resistance of insulin resistance (HOMA-IR) at 6 months. Particularly, the reduction of choline was predictive of long-term (2-year) improvements in fasting glucose (p=0.007), insulin (p=0.002), and HOMA-IR (p &amp;lt;0.001). We found significant interactions between dietary fat intake and ΔTMAO for changes in fasting glucose, insulin, and HOMA-IR (Pinteraction &amp;lt;0.05); among participants who consumed a high-fat diet, greater increase in TMAO was related to less improvements of the outcomes. In addition, ΔL-carnitine and Δcholine were also significantly related to changes in amino acids (including branched-chain and aromatic amino acids). However, the associations of ΔTMAO, Δcholine, and ΔL-carnitine with the diabetes-related traits were independent of the changes in amino acids. In conclusion, weight-loss-diet-induced changes in TMAO, choline, and L-carnitine were significantly associated with the improvements in glycemia and insulin sensitivity, regardless concurrent changes in diabetes-risk related amino acids. Dietary fat intake may modify the associations of changes in TMAO with the improvements of diabetes-related traits. Disclosure Y. Heianza: None. D. Sun: None. G. Bray: Advisory Panel; Self; Herbalife International of America, Inc., Novo Nordisk A/S. L. Qi: None.

GSH levels affect weight loss in individuals with metabolic syndrome and obesity following dietary therapy

This study examined the effects of redox status markers on metabolic syndrome (MetS) and obesity before and after dietary intervention and exercise for weight loss. A total of 103 adults suffering from MetS and obesity participated in this study and followed a personalized diet plan for 6 months. Body weight, body fat (BF) percentage (BF%), respiratory quotient (RQ) and the redox status markers, reduced glutathione (GSH), thiobarbituric acid reactive substances (TBARS) and protein carbonyls (CARB), were measured twice in each individual, before and after intervention. Dietary intervention resulted in weight loss, a reduction in BF% and a decrease in RQ. The GSH levels were significantly decreased following intervention, while the levels of TBARS and CARB were not affected. Based on the initial GSH levels, the patients were divided into 2 groups as follows: The high GSH group (GSH, >3.5 µmol/g Hb) and the low GSH group (GSH <3.5 µmol/g Hb). Greater weight and BF loss were observed in patients with high GSH levels. It was observed that patients with MetS and obesity with high GSH values responded better to the dietary therapy, exhibiting more significant changes in weight and BF%. This finding underscores the importance of identifying redox status markers, particularly GSH, in obese patients with MetS. Knowing the levels of GSH may aid in developing a better design of an individualized dietary plan for individuals who wish to lose weight.

HDL cholesterol efflux capacity and cholesteryl ester transfer are associated with body mass, but are not changed by diet-induced weight loss: A randomized trial in abdominally obese men

Background and aimsObesity is associated with a lower HDL-mediated cholesterol efflux from macrophages and a higher CETP (cholesteryl ester transfer protein) activity, but effects of weight loss are not clear. In addition, associations with visceral and subcutaneous adipose tissue are not known. We therefore investigated effects of diet-induced weight loss on HDL-mediated cholesterol efflux and cholesterol ester (CE) transfer in abdominally obese men. Differences between normal-weight and abdominally obese men were also examined. MethodsTwenty-five apparently healthy, normal-weight men (waist circumference: <94 cm) and 52 abdominally obese men (waist circumference: 102–110 cm) were included. Abdominally obese subjects were randomly allocated to a dietary weight-loss intervention group or a no–weight loss control group. Individuals from the intervention group followed a very-low-calorie diet for 6 weeks to obtain a waist circumference below 102 cm, followed by a 2-week weight-stable period. Cholesterol efflux was measured in BODIPY-labeled murine J774 macrophages. CE transfer was measured by quantifying the transfer of CE from radiolabeled exogenous HDL to apoB-containing lipoproteins. ResultsCholesterol efflux capacity was 9 percentage point (pp) lower in abdominally obese than in normal-weight men (p≤0.001), while CE transfer was 5 pp higher (p≤0.01). Diet-induced weight-loss of 10.3 kg did not change cholesterol efflux and CE transfer. In addition, stepwise regression analysis did not suggest that the different fat depots are differently related to efflux capacity and CE transfer. ConclusionsAfter a 2-week weight-stable period, dietary weight loss of 10 kg did not improve ABCA1-mediated cholesterol efflux and CE transfer in abdominally obese men.

A one-year resistance training program following weight loss has no significant impact on body composition and energy expenditure in postmenopausal women living with overweight and obesity

Resistance training (RT) has been shown to decrease fat mass (FM), and increase fat-free mass (FFM), which can be a useful for weight loss maintenance. ObjectiveTo examine the effects of a 1-year RT intervention on weight loss maintenance following a 6-month dietary weight loss intervention. DesignFollowing a 6-month dietary weight loss intervention (−6% ± 5.8; 5.05 kg ± 4.45), 70 postmenopausal women living with overweight or obesity were randomized to a control group (n = 34) or a RT group (n = 36) (3×/week first 6 months, 2×/week last 6 months, 70–80% of 1-repetition maximum). Body composition (DXA), abdominal visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT) (CT scan), resting energy expenditure (EE) (indirect calorimetry), physical activity EE and total daily EE were measured (doubly-labelled water). ResultsA total of 54 participants completed the study (control group n = 29; RT group n = 25) and compliance to the RT program was on average 64%. Significant regains were noted for body weight 0.98 (3.71) kg vs. 1.33 (3.94) kg and FM regain 1.32 (2.69) kg vs. 0.81 (3.26) kg in control and RT groups after the 1-year weight maintenance phase. No group differences were noted. Resting EE and total daily EE did not change after the weight maintenance phase, and no differences were observed between groups. Both groups had significantly greater than predicted decrease in resting EE after the 6-month dietary intervention and at the end of the 1-year weight-loss maintenance phase. ConclusionsOur results suggest that a 1-year RT intervention following a 6-month dietary weight loss intervention does not improve weight loss maintenance, body composition or EE in post-menopausal women living with overweight or obesity.

A circadian rhythm-related MTNR1B genetic variant modulates the effect of weight-loss diets on changes in adiposity and body composition: the POUNDS Lost trial.

A common variant of the melatonin receptor 1B (MTNR1B) gene has been related to increased signaling of melatonin, a hormone previously associated with body fatness mainly through effects on energy metabolism. We examined whether the MTNR1B variant affects changes of body fatness and composition in response to a dietary weight loss intervention. The MTNR1B rs10830963 variant was genotyped for 722 overweight and obese individuals, who were randomly assigned to one of four diets varying in macronutrient composition. Anthropometric and body composition measurements (DXA scan) were collected at baseline and at 6 and 24 months of follow-up. Statistically significant interactions were observed between the MTNR1B genotype and low-/high-fat diet on changes in weight, body mass index (BMI), waist circumference (WC) and total body fat (p interaction = 0.01, 0.02, 0.002 and 0.04, respectively), at 6months of dietary intervention. In the low-fat diet group, increasing number of the sleep disruption-related G allele was significantly associated with a decrease in weight (p = 0.004), BMI (p = 0.005) and WC (p = 0.001). In the high-fat diet group, carrying the G allele was positively associated with changes in body fat (p = 0.03). At 2years, the associations remained statistically significant for changes in body weight (p = 0.02), BMI (p = 0.02) and WC (p = 0.048) in the low-fat diet group, although the gene-diet interaction became less significant. The results suggest that carriers of the G allele of the MTNR1B rs10830963 may have a greater improvement in body adiposity and fat distribution when eating a low-fat diet.

Changes in Gut Microbiota-Related Metabolites and Long-term Successful Weight Loss in Response to Weight-Loss Diets: The POUNDS Lost Trial.

OBJECTIVEAdiposity 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 METHODSThis 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).RESULTSIndividuals 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.CONCLUSIONSOverweight 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.

FEASIBILITY OF WEIGHTED VEST USE DURING A DIETARY WEIGHT LOSS INTERVENTION AND EFFECTS ON BODY COMPOSITION AND PHYSICAL FUNCTION IN OLDER ADULTS

While intentional weight loss in older adults with obesity yields clinically important health benefits there is a need to minimize the negative effects of weight loss on concomitant loss of muscle mass and strength. Data show wearing weighted vests during exercise improves lean mass and lower extremity strength, however the efficacy of wearing a weighted vest during a period of weight loss to mitigate muscle and strength loss is not known. This study examined the feasibility of daily weighted vest use during a dietary weight loss intervention, and examined effects of vest use on body composition and physical function in well-functioning older adults with obesity. Randomized, controlled pilot study. Wake Forest Baptist Medical Center in Winston-Salem, NC. 37 older (age=65-79 yrs), obese (BMI=30-40 kg/ m2) sedentary men and women. 22-week behavioral diet intervention (targeting 10% weight loss, 1100-1300 kcals/day) with (Diet+Vest; n=20) or without (Diet; n=17) weighted vest use (goal of 10 hours/ day with weight added weekly according to individual loss of body mass). Body composition by dual-energy x-ray absorptiometry and measures of physical function, mobility, and muscle strength/power. Average weighted vest use was 6.7±2.2 hours/day and the vest-wear goal of 10 hrs/day was achieved for 67±22% of total intervention days. Five participants reported adverse events from wearing the vest (all back pain or soreness). Both groups lost a similar amount of weight (Diet= -11.2±4.4 kg; Diet+Vest = -11.0±6.3 kg; p<0.001), with no differences between groups (p=0.25). Fat mass, lean mass, and % body fat decreased significantly (p<0.0001), with no differences between groups. Compared to Diet+Vest, the Diet intervention resulted in greater decreases in leg power (p<0.02), with no other between group differences in physical function. This pilot study showed that vest use during dietary weight loss is feasible and safe in well-functioning older adults with obesity. Larger studies are needed to definitively determine whether external replacement of lost weight during caloric restriction may preserve lower extremity muscle strength and power.

Dietary Weight-Loss Interventions Might Lower Early All-Cause Mortality

Obesity is associated with adverse health outcomes (e.g., early death, diabetes, heart disease), but whether dietary weight-loss interventions lower

Genetic variation of habitual coffee consumption and glycemic changes in response to weight-loss diet intervention: the Preventing Overweight Using Novel Dietary Strategies (POUNDS LOST) trial

Background: Coffee consumption has been associated with glucose metabolism and risk of type 2 diabetes.Objective: We examined whether the genetic variation determining habitual coffee consumption affected glycemic changes in response to weight-loss dietary intervention.Design: A genetic risk score (GRS) was calculated based on 8 habitual coffee consumption-associated single nucleotide polymorphisms. We used general linear models to test changes in glycemic traits in groups randomly assigned to high- and low-fat diets according to tertiles of the GRS.Results: We observed significant interactions between the GRS and low compared with high dietary fat intake on 6-mo changes in fasting insulin and homeostasis model assessment of insulin resistance (HOMA-IR) (P-interaction = 0.023 and 0.022, respectively), adjusting for age, sex, race, physical activity, smoking, alcohol, seasonal variation, and baseline values of the respective outcomes. Participants with a higher GRS of habitual coffee consumption showed a greater reduction in fasting insulin and a marginally greater decrease in HOMA-IR in the low-fat diet intervention group.Conclusions: Our data suggest that participants with genetically determined high coffee consumption may benefit more by eating a low-fat diet in improving fasting insulin and HOMA-IR in a short term. This trial was registered at clinicaltrials.gov as NCT00072995 and NCT03258203.