Weight Maintenance Period Research Articles

Weight loss, weight maintenance, and adaptive thermogenesis

Diet-induced weight loss is accompanied by adaptive thermogenesis, ie, a disproportional or greater than expected reduction of resting metabolic rate (RMR). The aim of this study was to investigate whether adaptive thermogenesis is sustained during weight maintenance after weight loss. Subjects were 22 men and 69 women [mean ± SD age: 40 ± 9 y; body mass index (BMI; in kg/m(2)): 31.9 ± 3.0]. They followed a very-low-energy diet for 8 wk, followed by a 44-wk period of weight maintenance. Body composition was assessed with a 3-compartment model based on body weight, total body water (deuterium dilution), and body volume. RMR was measured (RMRm) with a ventilated hood. In addition, RMR was predicted (RMRp) on the basis of the measured body composition: RMRp (MJ/d) = 0.024 × fat mass (kg) + 0.102 × fat-free mass (kg) + 0.85. Measurements took place before the diet and 8, 20, and 52 wk after the start of the diet. The ratio of RMRm to RMRp decreased from 1.004 ± 0.077 before the diet to 0.963 ± 0.073 after the diet (P < 0.001), and the decrease was sustained after 20 wk (0.983 ± 0.063; P < 0.01) and 52 wk (0.984 ± 0.068; P < 0.01). RMRm/RMRp was correlated with the weight loss after 8 wk (P < 0.01), 20 wk (P < 0.05), and 52 wk (P < 0.05). Weight loss results in adaptive thermogenesis, and there is no indication for a change in adaptive thermogenesis up to 1 y, when weight loss is maintained. This trial was registered at clinicaltrials.gov as NCT01015508.

Benefit of a low-fat over high-fat diet on vascular health during alternate day fasting

Background:Alternate day fasting (ADF) with a low-fat (LF) diet improves brachial artery flow-mediated dilation (FMD). Whether these beneficial effects can be reproduced with a high-fat (HF) diet remains unclear.Objective:This study compared the effects of ADF-HF to ADF-LF regimens on FMD. The role that adipokines have in mediating this effect was also investigated.Methods:Thirty-two obese subjects were randomized to an ADF-HF (45% fat) or ADF-LF diet (25% fat), consisting of two phases: (1) a 2-week baseline weight maintenance period and (2) an 8-week ADF weight loss period. Food was provided throughout the study.Results:Body weight was reduced (P<0.0001) in the ADF-HF (4.4±1.0 kg) and ADF-LF group (3.7±0.7 kg). FMD decreased (P<0.05) by ADF-HF relative to baseline (7±1 to 5±2%) and increased (P<0.05) by ADF-LF (5±1 to 7±2%). Blood pressure remained unchanged in both groups. Adiponectin increased (P<0.05) in the ADF-HF (43±7%) and ADF-LF group (51±7%). Leptin and resistin decreased (P<0.05) in the ADF-HF (32±5% 23±5%) and ADF-LF group (30±3% 27±4%). Increases in adiponectin were associated with augmented FMD in the ADF-LF group only (r=0.34, P=0.03).Conclusion:Thus, improvements in FMD with ADF may only occur with LF diets and not with HF diets, and adipokines may not have a significant role in mediating this effect.

Abstract 161: Alternate Day Fasting With a High Fat and Low Fat Diet: Is Brachial Artery Flow Mediated Dilation Mediated by Adipokine Physiology?

Background Calorie restriction (CR) with variable macronutrient distributions has yielded inconsistent effects on brachial artery flow mediated dilation (FMD) related to weight loss and adipocyte physiology. Alternate day fasting (ADF) is a modified form of CR that has already elicited favorable changes in body weight and adipokine levels in both high fat (ADF-HF) and low fat (ADF-LF) background diets. However, the degree to which adipokines mediate vascular biology mechanisms on an ADF regimen is still unclear. This study examined if beneficial changes in body weight and adipokines influences endothelial function in ADF-HF and ADF-LF diets. Methods Thirty-two obese subjects were randomized to an ADF-HF (45% fat) or ADF-LF diet (25% fat), which consisted of two phases: 1) a 2-week baseline weight maintenance period, and 2) an 8-week ADF weight loss period. All food was provided to subjects. Results Body weight was reduced (P &lt; 0.0001) by ADF-HF (5 ± 1%) and by ADF-LF (4 ± 1%). Fat mass decreased (P &lt; 0.0001) by ADF-HF (5 ± 1 kg) and ADF-LF (4 ± 1 kg). Fat free mass remained unchanged. Waist circumference decreased (P &lt; 0.001) by ADF-HF (7 ± 1 cm) and ADF-LF (7 ± 1 cm). FMD decreased (P &lt; 0.05) in ADF-HF (2 ± 2%) and increased (P &lt; 0.05) in ADF-LF (2 ± 2%). Adiponectin increased (P &lt; 0.05) in ADF-HF (43 ± 7%) and in ADF-LF (51 ± 7%). Leptin decreased (P &lt; 0.05) in ADF-HF (32 ± 5%) and in ADF-LF (30 ± 3%). Resistin decreased (P &lt; 0.05) in ADF-HF (23 ± 5%) and ADF-LF (27 ± 4%). Increases in adiponectin were associated with augmented FMD post-treatment in the ADF-LF group only (r = 0.34, P = 0.03). Leptin and resistin were not correlated with changes in FMD. Conclusion Thus, an ADF-LF diet produces more favorable increases in FMD which are correlated with increased adiponectin as compared to the ADF-HF diet. These findings are important in terms of developing future behavioral modifications in energy restriction and macronutrient distribution that will improve vascular health.

Dietary protein intake, energy deficit, and nitrogen balance in normal‐weight adults: a randomized controlled trial

Consuming protein at levels higher than the recommended dietary allowance (RDA) may be metabolically advantageous for overweight and obese individuals attempting weight loss. However, the dose‐response characteristics that define the optimal level of dietary protein necessary to sustain measures of metabolic homeostasis during short‐term energy deficit (ED) in normal‐weight adults remain unclear. Thirty‐two men and 7 women participated in a 31‐day randomized trial providing diets containing protein at either the RDA (0.8 g·kg−1·d−1), 2X‐RDA (1.6 g·kg−1·d−1), or 3X‐RDA (2.4 g·kg−1·d−1). A weight maintenance (WM, days 1–10) period was followed by 21 days of ED (days 11–31); energy intake was restricted to 60% of daily requirements. Nitrogen balance (NBAL) was assessed during WM (day 9) and throughout ED on days 14, 17, 24, and 30. Independent of protein, NBAL (mgN·kg−1·d−1) was lower (P &lt; 0.05) at the start of ED (day 14, −40 ± 5) compared to WM (day 9, −10 ± 5). NBAL remained negative at the conclusion of ED (day 30) for RDA (−39 ± 8). However, NBAL increased (P &lt; 0.05) rapidly and was maintained at levels comparable to WM beginning on day 17 for 2X‐RDA (0 ± 8), yet failed to achieve WM levels until day 30 (−7 ± 10) for 3X‐RDA. These data confirm that high protein diets conserve NBAL during short‐term ED, but suggest no beneficial effect of protein at levels beyond 2X‐RDA, as 3X‐RDA failed to further enhance nitrogen adaptation.Supported by USAMRMC and USDA ARS

Energy intake modulates intramuscular mTORC1 signaling and ubiquitin‐mediated proteolysis during energy deficit independent of dietary protein variations

Effects of variations in habitual and acute dietary protein consumption on intracellular regulators of human skeletal muscle mass during energy deficit (ED) were investigated. Using a randomized‐block design, 32 men and 7 women consumed diets providing protein at 0.8, 1.6, or 2.4 g·kg−1·d−1 for 31 days. A 10‐day weight maintenance (WM) period preceded 21 days of ED, during which energy intake was reduced to 60% of daily requirements. Phosphorylation of mTORC1 associated signaling proteins, protein ubiquitylation (Ub), and NFκB expression were assessed in vastus lateralis muscle samples obtained after an overnight fast (FAST) and again 120 min after consuming a mixed meal (480 kcal, 20 g protein; FED) on days 10 and 31. Independent of dietary protein level and feeding state, Ub was 25% higher (P&lt; 0.05) for ED versus WM. Energy state and feeding altered p70S6K1 phosphorylation, as FED‐ED levels were 26% lower than FED‐WM (energy‐by‐feeding, P&lt; 0.05). Overall, Akt and rpS6 phosphorylation were higher (P&lt; 0.05), and NFκB and Ub were lower (P&lt; 0.05), for FED versus FAST. These data suggest that ED may upregulate intramuscular ubiquitin‐mediated proteolysis, and attenuate p70S6K1 sensitivity to feeding, although energy consumption, independent of habitual protein intake, may confer skeletal muscle protection through concomitant stimulation of mTORC1 signaling and inhibition of Ub during ED.Supported by USAMRMC, EMU CHHS SSSA, and USDA ARS

Alternate day fasting with a high fat diet: Impact on body weight, body composition, and coronary heart disease risk profile in obese adults

BackgroundAlternate day fasting (ADF) with a low‐fat (LF) diet is effective for weight loss and cardio‐protection. However, the applicability of these findings is questionable as most Americans consume a high‐fat (HF) diet. This study examined if these beneficial changes in weight and coronary heart disease (CHD) risk can be reproduced if a HF diet is used in place of a LF diet during ADF.MethodsThirty‐two obese subjects were randomized to an ADF‐HF (45% fat) or ADF‐LF diet (25% fat), which consisted of two phases: 1) a 2‐week baseline weight maintenance period, and 2) an 8‐week ADF weight loss period. All food was provided to subjects.ResultsBody weight was reduced (P &lt; 0.0001) by ADF‐HF (5 ± 1%) and by ADF‐LF (4 ± 1%). Fat mass decreased (P &lt; 0.0001) by ADF‐HF (5 ± 1 kg) and ADF‐LF (4 ± 1 kg). Fat free mass remained unchanged. Waist circumference decreased (P &lt; 0.001) by ADF‐HF (7 ( 1 cm) and ADF‐LF (7 ( 1 cm). LDL cholesterol and triacylglycerol concentrations were reduced (P &lt; 0.01) by both interventions (ADF‐HF: 18 ( 5%, 14 ( 5%; ADF‐LF: 24 ( 3%, 14 ( 4%). The proportion of small LDL particles decreased (P &lt; 0.05) in the ADF‐HF and ADF‐LF groups by 8 ( 3% and 10 ( 4%.ConclusionThus, an ADF‐HF diet produces similar reductions in weight and CHD risk as an ADF‐LF diet. These findings are important in terms of diet tolerability and long‐term adherence to ADF diets.

Abstract P410: Alternate Day Fasting with a High Fat Diet: Impact on Body Weight, Body Composition, and Coronary Heart Disease Risk Profile in Obese Adults

Background: Alternate day fasting (ADF) with a low-fat (LF) diet is effective for weight loss and cardio-protection. However, the applicability of these findings is questionable as most Americans consume a high-fat (HF) diet. This study examined if these beneficial changes in weight and coronary heart disease (CHD) risk can be reproduced if a HF diet is used in place of a LF diet during ADF. Methods: Thirty-two obese subjects were randomized to an ADF-HF (45% fat) or ADF-LF diet (25% fat), which consisted of two phases: 1) a 2-week baseline weight maintenance period, and 2) an 8-week ADF weight loss period. All food was provided to subjects. Results: Body weight was reduced (P &lt; 0.0001) by ADF-HF (5 ± 1%) and by ADF-LF (4 ± 1%). Fat mass decreased (P &lt; 0.0001) by ADF-HF (5 ± 1 kg) and ADF-LF (4 ± 1 kg). Fat free mass remained unchanged. Waist circumference decreased (P &lt; 0.001) by ADF-HF (7 ± 1 cm) and ADF-LF (7 ± 1 cm). LDL cholesterol and triacylglycerol concentrations were reduced (P &lt; 0.01) by both interventions (ADF-HF: 18 ± 5%, 14 ± 5%; ADF-LF: 24 ± 3%, 14 ± 4%). The proportion of small LDL particles decreased (P &lt; 0.05) in the ADF-HF and ADF-LF groups by 8 ± 3% and 10 ± 4%. Conclusion: Thus, an ADF-HF diet produces similar reductions in weight and CHD risk as an ADF-LF diet. These findings are important in terms of diet tolerability and long-term adherence to ADF diets.

Physiological Response of Adipocytes to Weight Loss and Maintenance

BackgroundMetabolic processes in adipose tissue are dysregulated in obese subjects and, in response to weight loss, either normalize or change in favor of weight regain.ObjectiveTo determine changes in adipocyte glucose and fatty acid metabolism in relation to changes in adipocyte size during weight loss and maintenance.MethodsTwenty-eight healthy subjects (12 males), age 20–50 y, and BMI 28–35 kg/m2, followed a very low energy diet for 2 months, followed by a 10-month period of weight maintenance. Body weight, body composition (deuterium dilution and BodPod), protein levels (Western blot) and adipocyte size were assessed prior to and after weight loss and after the 10-month follow-up.ResultsA 10% weight loss resulted in a 16% decrease in adipocyte size. A marker for glycolysis decreased (AldoC) during weight loss in association with adipocyte shrinking, and remained decreased during follow-up in association with weight maintenance. A marker for fatty acid transport increased (FABP4) during weight loss and remained increased during follow-up. Markers for mitochondrial beta-oxidation (HADHsc) and lipolysis (ATGL) were only increased after the 10-month follow-up. During weight loss HADHsc and ATGL were coordinately regulated, which became weaker during follow-up due to adipocyte size-related changes in HADHsc expression. AldoC was the major denominator of adipocyte size and body weight, whereas changes in ATGL during weight loss contributed to body weight during follow-up. Upregulation of ATGL and HADHsc occured in the absence of a negative energy balance and was triggered by adipocyte shrinkage or indicated preadipocyte differentiation.ConclusionMarkers for adipocyte glucose and fatty acid metabolism are changed in response to weight loss in line with normalization from a dysregulated obese status to an improved metabolic status.Trial RegistrationClinicalTrials.gov NCT01015508

Cell volume: Role in obesity and its maintenance minireview

Keeping volume within certain limits is a prerequisite for cell integrity and proper function. The defense against excess cell swelling is accomplished also by a reduction of the intracellular osmolarity by synthesis of osmotically less active macromolecules from their specific subunits (proteosynthesis and lipogenesis). At the same time proteolysis and lipolysis is inhibited. Conversely, cell shrinkage stimulates lipolysis, degradation of proteins to amino acids, degradation of glycogen to glucosephosphate and simultaneously protein, lipid and glycogen synthesis is inibited. The degradation products are osmotically more active than the macromolecules and their breakdown generates cellular osmolarity resulting in water entry into cells. Recently new interesting view of chronic changes of the cell volume and its role in model of body weight loss and regain in obesity is considered; secretion profile of adipocytes is related to their size. Decrease of body weight is constituted by the drop of fat in adipocytes, they consequently shrink. Surrounding extracellular matrix has to adjust to traction forces. To ascertain a sufficient supply of glucose and fat for re-storage, adipocytes change their pattern of secreted adipokines altering the total body metabolism and promoting energy intake. Shrunken adipocytes show insulin resistance, whereas glucose uptake is facilitated in osmotically swollen adipocytes. Compensating mechanism in patients on very-low calorie diet during weight maintenance period includes increase in water content of adipose tissue correlating with increase of insulin sensitivity. Consideration of participation these mechanisms might bring new insight into understanding of obesity pathophysiology and treatment.

TFAP2B-Dietary Protein and Glycemic Index Interactions and Weight Maintenance after Weight Loss in the DiOGenes Trial

Background:TFAP2B rs987237 is associated with obesity and has shown interaction with the dietary fat-to-carbohydrate ratio, which has an effect on weight loss. We investigated interactions between rs987237 and protein-to-carbohydrate ratio or glycemic index (GI) in relation to weight maintenance after weight loss. Methods: This study included 742 obese individuals from 8 European countries who participated in the Diet, Obesity, and Genes (DiOGenes) trial, lost ≥8% of their initial body weight during an 8-week low-calorie diet and were randomized to one of 5 ad libitum diets with a fixed energy percentage from fat: either low-protein/low-GI, low-protein/high-GI, high-protein/low-GI, or high-protein/high-GI diets, or a control diet for a 6-month weight maintenance period. Using linear regression analyses and additive genetic models, we investigated main and dietary interaction effects of TFAP2B rs987237 in relation to weight maintenance. Results: In total, 468 completers of the trial were genotyped for rs987237. High-protein diets were beneficial for weight maintenance in the AA genotype group (67% of participants), but in the AG and GG groups no differences were observed for low- or high-protein diets. On the high-protein diet, carriers of the obesity risk allele (G allele) regained 1.84 kg (95% CI: 0.02; 3.67, p = 0.047) more body weight per risk allele than individuals on a low-protein diet. There was no interaction effect between rs987237 and GI on weight maintenance. Conclusion:TFAP2B rs987237 and dietary protein/carbohydrate interacted to modify weight maintenance. Considering the carbohydrate proportion of the diet, the interaction was different from the previously reported rs987237-fat-to-carbohydrate ratio interaction for weight loss. Thus, TFAP2B-macronutrient interactions might diverge depending on the nutritional state.

Intermittent fasting combined with calorie restriction is effective for weight loss and cardio-protection in obese women

BackgroundIntermittent fasting (IF; severe restriction 1 d/week) facilitates weight loss and improves coronary heart disease (CHD) risk indicators. The degree to which weight loss can be enhanced if IF is combined with calorie restriction (CR) and liquid meals, remains unknown.ObjectiveThis study examined the effects of IF plus CR (with or without a liquid diet) on body weight, body composition, and CHD risk.MethodsObese women (n = 54) were randomized to either the IFCR-liquid (IFCR-L) or IFCR-food based (IFCR-F) diet. The trial had two phases: 1) 2-week weight maintenance period, and 2) 8-week weight loss period.ResultsBody weight decreased more (P = 0.04) in the IFCR-L group (3.9 ± 1.4 kg) versus the IFCR-F group (2.5 ± 0.6 kg). Fat mass decreased similarly (P < 0.0001) in the IFCR-L and IFCR-F groups (2.8 ± 1.2 kg and 1.9 ± 0.7 kg, respectively). Visceral fat was reduced (P < 0.001) by IFCR-L (0.7 ± 0.5 kg) and IFCR-F (0.3 ± 0.5 kg) diets. Reductions in total and LDL cholesterol levels were greater (P = 0.04) in the IFCR-L (19 ± 10%; 20 ± 9%, respectively) versus the IFCR-F group (8 ± 3%; 7 ± 4%, respectively). LDL peak particle size increased (P < 0.01), while heart rate, glucose, insulin, and homocysteine decreased (P < 0.05), in the IFCR-L group only.ConclusionThese findings suggest that IF combined with CR and liquid meals is an effective strategy to help obese women lose weight and lower CHD risk.

Alternate day fasting (ADF) with a high-fat diet produces similar weight loss and cardio-protection as ADF with a low-fat diet

Alternate day fasting (ADF) with a low-fat (LF) diet is effective for weight loss and cardio-protection. However, the applicability of these findings is questionable as the majority of Americans consume a high-fat (HF) diet. ObjectiveThe goal of this study was to determine if these beneficial changes in body weight and coronary heart disease (CHD) risk can be reproduced if an HF background diet is used in place of an LF diet during ADF. MethodsThirty-two obese subjects were randomized to an ADF-HF (45% fat) or ADF-LF diet (25% fat), which consisted of two phases: 1) a 2-week baseline weight maintenance period, and 2) an 8-week ADF weight loss period. All food was provided during the study. ResultsBody weight was reduced (P<0.0001) by ADF-HF (4.8%±1.1%) and by ADF-LF (4.2%±0.8%). Fat mass decreased (P<0.0001) by ADF-HF (5.4±1.5kg) and ADF-LF (4.2±0.6kg). Fat free mass remained unchanged. Waist circumference decreased (P<0.001) by ADF-HF (7.2±1.5cm) and ADF-LF (7.3±0.9cm). LDL cholesterol and triacylglycerol concentrations were reduced (P<0.001) by both interventions (ADF-HF: 18.3%±4.6%, 13.7%±4.8%; and ADF-LF: 24.8%±2.6%, 14.3%±4.4%). HDL cholesterol, blood pressure, and heart rate remained unchanged. There were no between-group differences for any parameter. ConclusionThese findings suggest that an ADF-HF diet is equally as effective as an ADF-LF diet in helping obese subjects lose weight and improve CHD risk factors.

Acute nutrient consumption attenuates intramuscular 26S proteasome activity during energy deficit

The effects of dietary protein and feeding during energy deficit (ED) on cellular regulators of muscle proteolysis are not well documented. This study examined intramuscular caspase‐3 and 26S proteasome responses to feeding during sustained ED in adults consuming varying levels of dietary protein. Using a randomized*block design, 32 men and 7 women were assigned to either standard (0.8 g·kg−1·d−1; n =13), moderate (1.6 g·kg−1·d−1; n =14), or high (2.4 g·kg−1·d−1; n =12) protein diets for 31 days. A 10 day weight maintenance period was followed by 21 days of ED, during which energy intake was restricted to 60% of total daily energy expenditure. Enzyme activities were assessed using fluorescence‐based assays and muscle samples obtained on days 10 and 31 following an overnight fast (FAST) and 120 min after consuming a mixed meal (480 kcals, 20 g protein; FED). The activity of the 26S proteasome's β1, β2, and β5 subunits were 28%, 14% and 22% lower (P &lt; 0.05), respectively, for FED relative to FAST regardless of energy status and dietary protein. Caspase‐3 activity remained steady in response to feeding and was not influenced by energy and protein manipulations. These data demonstrate that feeding attenuates ubiquitin‐mediated proteolysis, suggesting a novel cellular mechanism for preservation of muscle mass independent of habitual dietary protein intake and decrements in energy balance. Supported by USAMRMC, USDA ARS GFHNRC and EMU CHHS FRF

A high protein diet upregulates whole‐body protein turnover during energy deficit

The effects of dietary protein level on whole‐body protein turnover (WBPTO) during energy deficit (ED) are not well described. Using a randomized‐block design, 24 males and five females (21 ± 3 yr) participated in a controlled trial. Volunteers consumed either standard (SP; 0.8 g·kg−1·d−1), moderate (MP; 1.6 g·kg−1·d−1), or high (HP; 2.4 g·kg−1·d−1) protein diets for 31 days. A weight maintenance (WM, days 1–10) period was followed by 21 days of ED (days 11–31), during which energy intake was restricted to 60% of total daily energy expenditure. Whole‐body protein breakdown, synthesis, and oxidation were determined at rest during WM (day 10) and ED (day 31) using primed, continuous [13C]‐leucine infusions. Volunteers lost (P &lt; 0.05) 3.3 ± 0.9 kg body mass in response to ED regardless of dietary protein level. Protein breakdown decreased (P &lt; 0.05) in response to ED for SP and MP diets, but did not change for HP. Synthesis decreased (P &lt; 0.05) following ED regardless of dietary protein level. Protein oxidation (μmol·kg−1·h−1) increased linearly between SP (9.7 ± 0.5), MP (11.8 ± 0.5), and HP (13.9 ± 0.5) diets during WM, with increased oxidation observed only for HP (16 ± 0.7) during ED (diet‐by‐energy interaction, P &lt; 0.05). These data demonstrate that the level of dietary protein intake modulates WBPTO during sustained ED, as consumption of a high protein diet upregulates WBPTO during ED.

Psychobehavioural Factors Are More Strongly Associated with Successful Weight Management Than Predetermined Satiety Effect or Other Characteristics of Diet

This study aimed to investigate factors associated with weight management, especially whether satiety value of food as a part of a weight-maintenance diet would affect self-regulation of food intake and weight management. Altogether 82 obese subjects completed the study consisting of weight-loss and weight-maintenance (WM) periods. During the WM, subjects were randomized into higher- and lower-satiety food groups. No differences were observed in the changes in body weight, energy intake, or eating behaviour between the groups, even despite the different macronutrient compositions of the diets. However, when regarding all study subjects, success in WM was most strongly associated with a greater increase in the flexible control of eating and experience of greater easiness of WM and control of food intake and a greater decrease in uncontrollable eating and psychological distress. Psychobehavioural factors seem to be more strongly associated with successful weight management than the predetermined satiety effect or other characteristics of the diet.

Effects of Weight Loss and Long-Term Weight Maintenance With Diets Varying in Protein and Glycemic Index on Cardiovascular Risk Factors

Background— We sought to separately examine the effects of either weight loss or diets varying in protein content and glycemic index without further changes in body weight on cardiovascular risk factors within the Diet, Obesity, and Genes study (DiOGenes). Methods and Results— DiOGenes is a pan-European controlled dietary intervention study in 932 overweight adults who first lost body weight on an 8-week low-calorie diet and were then randomized to 1 of 5 ad libitum diets for 26 weeks. The diets were either high or low protein or high or low glycemic index in 4 combinations or control. Weight loss (−11.23 kg; 95% confidence interval, −11.54 to −10.92; P &lt;0.001) reduced high-sensitivity C-reactive protein (−1.15 mg/L; 95% confidence interval, −1.30 to −0.41; P &lt;0.001), low- and high-density lipoprotein cholesterol, triglycerides, and blood pressure. During the 26-week weight maintenance period in the intention-to-treat analysis, the further decrease of high-sensitivity C-reactive protein blood levels was −0.46 mg/L greater (95% confidence interval, −0.79 to −0.13) in the groups assigned to low-glycemic-index diets than in those on high-glycemic-index diets ( P &lt;0.001). Groups on low-protein diets achieved a −0.25 mg/L greater reduction in high-sensitivity C-reactive protein (95% confidence interval, −0.59 to −0.17) than those on high-protein diets ( P &lt;0.001), whereas lipid profiles and blood pressure were not differently affected. Conclusions— This large-scale intervention study clearly separates weight loss from dietary composition–related effects. Low-glycemic-index carbohydrates and, to a lesser extent, low-protein intake may specifically reduce low-grade inflammation and associated comorbidities in overweight/obese adults. Clinical Trial Registration— http://www.clinicaltrials.gov . Unique identifier: NCT00390637.

Blood profiling of proteins and steroids during weight maintenance with manipulation of dietary protein level and glycaemic index

Weight regain after weight loss is common. In the Diogenes dietary intervention study, a high-protein and low-glycaemic index (GI) diet improved weight maintenance. The objective of the present study was to identify (1) blood profiles associated with continued weight loss and weight regain (2) blood biomarkers of dietary protein and GI levels during the weight-maintenance phase. Blood samples were collected at baseline, after 8 weeks of low-energy diet-induced weight loss and after a 6-month dietary intervention period from female continued weight losers (n 48) and weight regainers (n 48), evenly selected from four dietary groups that varied in protein and GI levels. The blood concentrations of twenty-nine proteins and three steroid hormones were measured. The changes in analytes during weight maintenance largely correlated negatively with the changes during weight loss, with some differences between continued weight losers and weight regainers. Increases in leptin (LEP) and C-reactive protein (CRP) were significantly associated with weight regain (P<0·001 and P=0·005, respectively), and these relationships were influenced by the diet. Consuming a high-protein and high-GI diet dissociated the positive relationship between the change in LEP concentration and weight regain. CRP increased during the weight-maintenance period only in weight regainers with a high-protein diet (P<0·001). In addition, testosterone, luteinising hormone, angiotensinogen, plasminogen activator inhibitor-1, resistin, retinol-binding protein 4, insulin, glucagon, haptoglobin and growth hormone were also affected by the dietary intervention. The blood profile reflects not only the weight change during the maintenance period, but also the macronutrient composition of the dietary intervention, especially the protein level.

Predictors of weight loss maintenance and attrition during a 6‐month dietary intervention period: results from the DiOGenes study

There is a need to develop tools to predict individual weight loss maintenance and attrition prognosis. We aimed to identify predictors of weight loss maintenance outcome and attrition in subjects from eight European countries in the DiOGenes project. A total of 932 overweight/obese subjects (body mass index: 27-42 kg m(-2) ) were enrolled in an 8-week low-calorie diet (LCD). The 776 subjects (83%) who achieved at least 8% reduction in their initial body weight were randomized into five dietary arms varying in protein content and glycemic index for a 6-month weight maintenance period. Baseline characteristics, weight loss at weeks 1, 3 and 8 of LCD were assessed as predictors of weight loss maintenance and attrition using multivariate regression and correlation models. The multivariate model showed that the 6-month weight loss maintenance was predicted by: 7.889 - 0.343 × weight loss at week 3 + 1.505 × weight loss at week 8 + 2.422 × gender (0 = male and 1 = female gender) (R(2) = 51%, P = 0.0001). A greater weight loss at week 8 was associated with a lower attrition during the subsequent 6-month dietary intervention period (OR = 0.92, 95% CI: 0.88-0.97, P = 0.001). Furthermore, the men showed an increased likelihood for attrition during the dietary intervention period (OR = 1.54, 95% CI: 1.07-2.20, P = 0.02). A greater weight loss during 8 weeks of LCD and female gender predict better 6-month weight maintenance of weight loss, whereas the baseline characteristics did not predict outcome. Attrition could be strongly predicted by gender and weight loss during LCD.

The Effects of Weight LossVersusWeight Loss Maintenance on Sympathetic Nervous System Activity and Metabolic Syndrome Components

Sympathetic nervous system (SNS) overactivity participates in both the pathogenesis and adverse clinical complications of metabolic syndrome (MetS) obesity. We conducted a prospective lifestyle intervention trial to compare the effects of active weight loss and extended weight loss maintenance on SNS function and MetS components. Untreated subjects (14 males, four females; mean age, 53 ± 1 yr; body mass index, 30.9 ± 0.9 kg/m(2)) who fulfilled Adult Treatment Panel III criteria were randomized to 12-wk hypocaloric diet alone (n = 8) or together with aerobic exercise training (n = 10). This was followed by a 4-month weight maintenance period. Measurements of muscle sympathetic nerve activity (MSNA) by microneurography, whole-body norepinephrine kinetics, substrate oxidation by indirect calorimetry, baroreflex sensitivity, plasma renin activity (PRA), and MetS components were performed. Body weight decreased by 9.3 ± 0.8% at wk 12 (P < 0.001), and this was maintained. During active weight loss, norepinephrine spillover rate decreased by 23 ± 16% (P = 0.004), MSNA by 25 ± 3 bursts per 100 heartbeats (P < 0.001), and PRA by 0.25 ± 0.09 ng/ml · h (P = 0.007), whereas baroreflex sensitivity increased by 5.2 ± 2.2 msec/mm Hg (P = 0.005). After weight maintenance, beneficial effects of weight loss on norepinephrine spillover rate were preserved, whereas PRA and MSNA rebounded (by 0.24 ± 0.11 ng/ml · h, P = 0.02; and 20 ± 5 bursts/100 heartbeats, P = 0.0003), and baroreflex sensitivity was attenuated. Divergent effects of successful weight loss maintenance on whole-body norepinephrine spillover rate and MSNA suggest organ-specific differentiation in SNS adaptation to weight loss under conditions of negative vs. stable energy balance.

No long-term weight maintenance effects of gelatin in a supra-sustained protein diet

In the short-term, gelatin showed stronger hunger suppression and less energy intake compared with other proteins. This study investigated if a supra-sustained gelatin–milk protein (GMP) diet improves weight maintenance (WM) compared with a sustained milk protein (SMP) diet and supra-sustained milk protein (SSMP) diet during a 4-months WM period after 8-week weight loss (WL) in sixty-five healthy subjects (28.6 ± 3.4 kg/m 2; 44 ± 10 years). Absolute protein intake was kept constant (sustained) throughout per subject. Diets were: protein(P)/fat(F)/carbohydrate(C): 15/40/45% of energy (En%) (SMP) and 30/25/45 En% (SSMP or GMP) for weeks 9–16. Diets on weeks 17–24: P/F/C: 30/35/35 En% (SMP) and 60/5/35 En% (SSMP or GMP). From weeks 8 to 16, and weeks 16 to 24, changes in BMI were similar between the GMP (− 0.4 ± 0.6 and 0.3 ± 0.7 kg/m 2 respectively), and the SMP (− 0.7 ± 0.9 and 0.1 ± 0.7 kg/m 2 respectively) and SSMP (− 0.6 ± 0.6 and 0.3 ± 0.6 kg/m 2 respectively) diets. Sparing of fat free mass (FFM): increases/decreases in FFM%/fat-mass% from weeks 8 to 16 were similar between the GMP and both control diets, and maintained from weeks 16 to 24. In conclusion, all 3 diets resulted in a successful WM period, while a GMP diet does not improve body weight maintenance and related variables after weight loss compared with a SMP and SSMP diet.