Exploratory analysis of reflective, reactive, and homeostatic eating behaviour traits on weight change during the 18-month NoHoW weight maintenance trial

Behaviour change interventions for weight management have found varied effect sizes and frequent weight re-gain after weight loss. There is interest in exploring whether differences in eating behaviour can be used to develop tailored weight management programs. This secondary analysis of an 18-month weight maintenance randomised controlled trial (RCT) aimed to investigate the association between individual variability in weight maintenance success and change in eating behaviour traits (EBT). Data was analysed from the NoHoW trial (Scott et al., 2019), which was designed to measure processes of change after weight loss of ≥5% body weight in the previous year. The sample included 1627 participants (mean age = 44.0 years, SD = 11.9, mean body mass index (BMI) = 29.7 kg/m2, SD = 5.4, gender = 68.7% women/31.3% men). Measurements of weight (kg) and 7 EBTs belonging to domains of reflective, reactive, or homeostatic eating were taken at 4 time points up to 18-months. Increases in measures of 'reactive eating' (binge eating, p < .001), decreases in 'reflective eating' (restraint, p < .001) and changes in 'homeostatic eating' (unlimited permission to eat, p < .001 and reliance on hunger and satiety cues, p < .05) were significantly and independently associated with concomitant weight change. Differences in EBT change were observed between participants who lost, maintained, or re-gained weight for all EBTs (p < .001) except for one subscale of intuitive eating (eating for physical reasons, p = .715). Participants who lost weight (n = 322) exhibited lower levels of reactive eating and higher levels of reflective eating than participants who re-gained weight (n = 668). EBT domains can identify individuals who need greater support to progress in weight management interventions. Increasing reflective eating and reducing reactive eating may enhance weight management success.

Effects of sustained weight loss on outcomes associated with obesity comorbidities and healthcare resource utilization

Objective

Determine the impact of long-term non-surgical weight loss maintenance on clinical relevance for osteoarthritis, cancer, opioid use, and depression/anxiety and healthcare resource utilization.

Methods

A cohort of adults receiving primary care within Geisinger Health System between 2001–2017 was retrospectively studied. Patients with ≥3 weight measurements in the two-year index period and obesity at baseline (BMI ≥30 kg/m²) were categorized: Obesity Maintainers (reference group) maintained weight within +/-3%; Weight Loss Rebounders lost ≥5% body weight in year one, regaining ≥20% of weight loss in year two; Weight Loss Maintainers lost ≥5% body weight in year one, maintaining ≥80% of weight loss. Association with development of osteoarthritis, cancer, opioid use, and depression/anxiety, was assessed; healthcare resource utilization was quantified. Magnitude of weight loss among maintainers was evaluated for impact on health outcomes.

Results

In total, 63,567 patients were analyzed including 67% Obesity Maintainers, 19% Weight Loss Rebounders, and 14% Weight Loss Maintainers; median follow-up was 9.7 years. Time until osteoarthritis onset was delayed for Weight Loss Maintainers compared to Obesity Maintainers (Logrank test p <0.0001). Female Weight Loss Maintainers had a 19% and 24% lower risk of developing any cancer (p = 0.0022) or obesity-related cancer (p = 0.0021), respectively. No significant trends were observed for opioid use. Weight loss Rebounders and Maintainers had increased risk (14% and 25%) of future treatment for anxiety/depression (both <0.0001). Weight loss maintenance of >15% weight loss was associated with the greatest decrease in incident osteoarthritis. Healthcare resource utilization was significantly higher for Weight Loss Rebounders and Maintainers compared to Obesity Maintainers. Increased weight loss among Weight Loss Maintainers trended with lower overall healthcare resource utilization, except for hospitalizations.

Conclusions

In people with obesity, sustained weight loss was associated with greater clinical benefits than regained short-term weight loss and obesity maintenance. Higher weight loss magnitudes were associated with delayed onset of osteoarthritis and led to decreased healthcare utilization.

Cost-effectiveness of bariatric surgery and non-surgical weight management programmes for adults with severe obesity: a decision analysis model

OBJECTIVES

To determine the most cost-effective weight management programmes (WMPs) for adults, in England with severe obesity (BMI ≥ 35 kg/m2), who are more at risk of obesity related diseases.

METHODS

An economic evaluation of five different WMPs: 1) low intensity (WMP1); 2) very low calorie diets (VLCD) added to WMP1; 3) moderate intensity (WMP2); 4) high intensity (Look AHEAD); and 5) Roux-en-Y gastric bypass (RYGB) surgery, all compared to a baseline scenario representing no WMP. We also compare a VLCD added to WMP1 vs. WMP1 alone. A microsimulation decision analysis model was used to extrapolate the impact of changes in BMI, obtained from a systematic review and meta-analysis of randomised controlled trials (RCTs) of WMPs and bariatric surgery, on long-term risks of obesity related disease, costs, quality adjusted life years (QALYs) and incremental cost-effectiveness ratios (ICERs) measured as incremental cost per QALY gained over a 30-year time horizon from a UK National Health Service (NHS) perspective. Sensitivity analyses explored the impact of long-term weight regain assumptions on results.

RESULTS

RYGB was the most costly intervention but also generated the lowest incidence of obesity related disease and hence the highest QALY gains. Base case ICERs for WMP1, a VLCD added to WMP1, WMP2, Look AHEAD, and RYGB compared to no WMP were £557, £6628, £1540, £23,725 and £10,126 per QALY gained respectively. Adding a VLCD to WMP1 generated an ICER of over £121,000 per QALY compared to WMP1 alone. Sensitivity analysis found that all ICERs were sensitive to the modelled base case, five year post intervention cessation, weight regain assumption.

CONCLUSIONS

RYGB surgery was the most effective and cost-effective use of scarce NHS funding resources. However, where fixed healthcare budgets or patient preferences exclude surgery as an option, a standard 12 week behavioural WMP (WMP1) was the next most cost-effective intervention.

The gravitostat protects diet-induced obese rats against fat accumulation and weight gain

The gravitostat is a novel homeostatic body weight-regulating mechanism, mostly studied in mice, and recently confirmed in obese humans. In the present study, we explored the effect of weight loading on metabolic outcomes, meal patterns and parameters linked to energy expenditure in both obese and lean rats. Diet-induced obese (DIO) and lean rats were implanted with capsules weighing either 15% of biological body weight (load) or empty capsules (1.3% of body weight; controls). Loading protected against fat accumulation more markedly in the DIO group. In line with this, the obesity-related impairment in insulin sensitivity was notably ameliorated in DIO rats upon loading, as revealed by the reduction in serum insulin levels and homeostatic model assessment for insulin resistance index scores. Although 24-hour caloric intake was reduced in both groups, this effect was greater in loaded DIO rats than in loaded lean peers. During days 10-16, after recovery from surgery, loading: (i) decreased meal size in both groups (only during the light phase in DIO rats) but this was compensated in lean rats by an increase in meal frequency; (ii) reduced dark phase locomotor activity only in lean rats; and (iii) reduced mean caloric efficiency in DIO rats. Muscle weight was unaffected by loading in either group. Dietary-obese rats are therefore more responsive than lean rats to loading.

Sitting Time, Type, and Context Among Long-Term Weight-Loss Maintainers

OBJECTIVE

This study aimed to investigate sitting time, the home sedentary environment, and physical activity among weight-loss maintainers in WW (formerly Weight Watchers).

METHODS

Participants were 4,305 weight-loss maintainers who had maintained ≥9.1 kg of weight loss (24.7 kg on average) for 3.3 years and had an average current BMI of 27.6 kg/m² . A control group of weight-stable individuals with obesity (n = 619) had an average BMI of 38.9 kg/m² . The Multicontext Sitting Time Questionnaire and Paffenbarger physical activity questionnaire were administered.

RESULTS

Weight-loss maintainers versus controls spent 3 hours less per day sitting during the week (10.9 vs. 13.9; η p 2 = 0.039; P = 0.0001) and weekends (9.7 vs. 12.6; η p 2 = 0.038). Weight-loss maintainers versus controls spent 1 hour less per day in non-work-related sitting using a computer or video games during the week (1.4 vs. 2.3; η p 2 = 0.03; P = 0.0001) and weekends (1.5 vs. 2.5; η p 2 = 0.03; P = 0.0001). Weight-loss maintainers versus controls had similar numbers of sedentary-promoting devices (15.8 vs. 14.8) and expended significantly more calories per week in physical activity (1,835 vs. 785; η p 2 = 0.036; P = 0.0001).

CONCLUSIONS

Weight-loss maintainers reported less time sitting than weight-stable individuals with obesity. Future research should test the efficacy of targeting sitting time to help promote long-term weight-loss maintenance.

Describing the Weight-Reduced State: Physiology, Behavior, and Interventions

Although many persons with obesity can lose weight by lifestyle (diet and physical activity) therapy, successful long-term weight loss is difficult to achieve, and most people who lose weight regain their lost weight over time. The neurohormonal, physiological, and behavioral factors that promote weight recidivism are unclear and complex. The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop in June 2019, titled "The Physiology of the Weight-Reduced State," to explore the mechanisms and integrative physiology of adaptations in appetite, energy expenditure, and thermogenesis that occur in the weight-reduced state and that may oppose weight-loss maintenance. The proceedings from the first session of this workshop are presented here. Drs. Michael Rosenbaum, Kevin Hall, and Rudolph Leibel discussed the physiological factors that contribute to weight regain; Dr. Michael Lowe discussed the biobehavioral issues involved in weight-loss maintenance; Dr. John Jakicic discussed the influence of physical activity on long-term weight-loss maintenance; and Dr. Louis Aronne discussed the ability of drug therapy to maintain weight loss.

Physiology of Energy Intake in the Weight-Reduced State

Physiological adaptations to intentional weight loss can facilitate weight regain. This review summarizes emerging findings on hypothalamic and brainstem circuitry in the regulation of body weight and identifies promising areas for research to improve therapeutic interventions for sustainable weight loss. There is good evidence that body weight is actively regulated in a homeostatic fashion similar to other physiological parameters. However, the defended level of body weight is not fixed but rather depends on environmental conditions and genetic background in an allostatic fashion. In an environment with plenty of easily available energy-dense food and low levels of physical activity, prone individuals develop obesity. In a majority of individuals with obesity, body weight is strongly defended through counterregulatory mechanisms, such as hunger and hypometabolism, making weight loss challenging. Among the options for treatment or prevention of obesity, those directly changing the defended body weight would appear to be the most effective ones. There is strong evidence that the mediobasal hypothalamus is a master sensor of the metabolic state and an integrator of effector actions responsible for the defense of adequate body weight. However, other brain areas, such as the brainstem and limbic system, are also increasingly implicated in body weight defense mechanisms and may thus be additional targets for successful therapies.

Physiology of the Weight-Reduced State: A Report from a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

Preventing regain of lost weight is the most difficult challenge in the treatment of obesity. The National Institute of Diabetes and Digestive and Kidney Diseases convened a workshop, "The Physiology of the Weight-Reduced State," on June 3 to 4, 2019, in order to explore the physiologic mechanisms of appetitive and metabolic adaptation that take place in the weight-reduced state and counter an individual's efforts to maintain reduced weight following weight loss.

Protein-Rich Diets for Weight Loss Maintenance

PURPOSE OF REVIEW

High-protein diets in the management of obesity have been around for many years and have been rigorously tested for their ability to induce weight loss. Comparably less is known about their effects on the maintenance of lost weight.

RECENT FINDINGS

Several small and a few large randomized trials have evaluated the efficacy of high-protein diets (20-35% of calories from protein; 1.2-1.9 g/kg∙day) compared with normal-protein diets (10-20% of calories from protein; 0.8-1.3 g/kg∙day), consumed mostly ad libitum during weight loss maintenance, i.e., after clinically significant weight loss. Most of these studies indicate that weight regain in the short term (3-12 months) is lower by 1-2 kg with high-protein diets than low-protein diets. This effect is attenuated with longer periods of observation, likely because of decreasing dietary compliance. In line with findings during the active weight loss phase, studies assessing the efficacy of protein-rich diets to improve weight loss maintenance report beneficial effects in the short term, which nevertheless dissipate over time.

The Weight Optimization Revamping Lifestyle using the Dietary Guidelines (WORLD) Study: Sustained Weight Loss Over 12 Months

OBJECTIVE

This study aimed to compare two energy-restricted, nutrient-dense diets at the upper or lower ends of the dietary fat recommendation range (lower fat [20% energy from fat] versus moderate fat [35%]) on weight loss using behavioral theory-based nutrition education.

METHODS

A total of 101 premenopausal women with overweight or obesity were randomized to an energy-restricted lower-fat or moderate-fat diet for 1 year. Interventions included 28 behavioral theory-based nutrition education sessions plus weekly exercise sessions.

RESULTS

Both treatment groups experienced weight loss (-5.0 kg for lower fat and -4.3 kg for moderate fat; P < 0.0001), but there was no difference in weight loss or fat intake between groups. Total and low-density lipoprotein cholesterol decreased (-3. 4 mg/dL and -3.8 mg/dL; P < 0.05), and high-density lipoprotein cholesterol increased (1.9 mg/dL; P < 0.05) in both groups at 12 months. Diet quality, assessed by the Healthy Eating Index, increased significantly at 4 months versus baseline (70.8 [0.9] vs. 77.8 [1.0]) and was maintained through 12 months. Higher Healthy Eating Index scores were associated with greater weight loss at 4 months (r = -0.2; P < 0.05).

CONCLUSIONS

In the context of a well-resourced, free-living weight-loss intervention, total fat intake did not change; however, theory-based nutrition education underpinned by food-based recommendations resulted in caloric deficits, improvements in diet quality, and weight loss that was sustained for 1 year.

Stabilization of BMIz Score is Associated with a Decrease in Visceral Fat in Children with Obesity

BMIz-score (BMIz) is commonly used to assess childhood obesity. Whether change in BMIz score predicts change in visceral fat remains unclear. The objective of the work was to study changes in visceral fat, cardiovascular fitness (CVF), and metabolic health over 6 months in children with stable/decreased-BMIz vs. increased-BMIz. Ninety children with obesity, referred for lifestyle intervention were studied (mean age 11±3.1 years, 50% girls, 22% Hispanic). Assessment included abdominal and total fat by dual X-ray absorptiometry (DXA), sub-maximal VO2 for CVF, anthropometrics, and fasting insulin, glucose, HDL-C, triglycerides, AST and ALT at 0 and 6 months. Sixty-three children (70%) showed a stable/decrease in BMIz over 6 months. There was no significant change in total body fat between groups (-1.3±2.9% in BMIz-stable/down vs. - 0.6 ± 2.6% BMIz-up, p=0.459); however, BMIz-stable/down group showed a decrease in visceral fat compared to the BMIz-up group (-258±650 g vs.+137±528 g, p=0.009). BMIz-stable/down group also demonstrated increased CVF (+1.2 ml/kg/min, p<0.001), not seen in the BMIz-up group. Neither group had significant changes in metabolic markers. Preventing BMIz increase in obese children predicts a significant decrease in visceral fat even if total body fat is unchanged. This is often associated with increased fitness. Thus, increasing fitness level and keeping BMI stable are strategic initial goals for obese children.

Frequency and Consistency of Self-Weighing to Promote Weight-Loss Maintenance

OBJECTIVE

This study aimed to investigate the roles of frequency and consistency of self-weighing in promoting weight-loss maintenance.

METHODS

Participants were 74 adults who completed a 3-month internet-based weight-loss program followed by a 9-month no-intervention maintenance period. Frequency of self-weighing was defined as the number of days that participants self-weighed during the maintenance period via a study-provided smart scale. Consistency was defined as the number of weeks that participants self-weighed at a certain frequency, with multiple minimum thresholds examined. Hierarchical regression analyses were used to assess associations among frequency, consistency, and weight change during the maintenance period.

RESULTS

Greater consistency was significantly associated with less weight regain when defined as the number of weeks that participants self-weighed on ≥6 d/wk or 7 d/wk (P values < 0.05). Contrary to hypotheses, frequency was not associated with weight change (P = 0.141), and there was not a significant interaction between frequency and consistency.

CONCLUSIONS

Results demonstrate that consistency of self-weighing may be more important than total frequency for preventing weight regain after the end of a weight-loss program. Further, results suggest that a high level of consistency (self-weighing for ≥6 d/wk or 7 d/wk) may be necessary to promote successful weight-loss maintenance.

The association between weight maintenance and session-by-session diet adherence, weight loss and weight-loss satisfaction

OBJECTIVE

The aim of this study was to assess the association between weight-loss maintenance and weight-loss satisfaction, adherence to diet and weight loss, all measured session-by-session during the weight-loss phase of cognitive behavioral therapy.

METHODS

The present exploratory study examined a subgroup of fifty-eight patients who participated in a randomized controlled trial and who lost at least the 10% of their baseline weight. Patients were grouped into weight-loss 'Maintainers' (i.e., those who maintained a weight loss of ≥ 10% of baseline body weight at 6 months after the weight-loss phase) and 'Regainers' (i.e., those who did not maintain > 10% weight loss at 6 months after the weight-loss phase). Body weight, adherence to diet and weight-loss satisfaction were measured session-by-session during the weight-loss phase.

RESULTS

Thirteen patients (22.4%) were classified as 'Regainers', and 45 (77.6%) as 'Maintainers'. Compared to 'Maintainers', 'Regainers' had a lower adherence to diet after the initial 11 weeks, and a progressively declining weight loss and weight-loss satisfaction from week 15 or 19 of the weight-loss phase. 11-week dietary adherence and 15-week weight loss were significantly associated with weight maintenance. Similar results were obtained using the amount of weight change as dependent variable.

CONCLUSIONS

Adherence to diet, weight loss and weight-loss satisfaction, measured during the late weight-loss phase, are associated with weight-loss maintenance.

LEVEL OF EVIDENCE

Level III, evidence obtained from well-designed cohort or case-control analytical studies.

Behavioral and Psychological Strategies of Long-Term Weight Loss Maintainers in a Widely Available Weight Management Program

OBJECTIVE

The study's purpose was to use validated questionnaires to identify novel behavioral and psychological strategies among weight loss maintainers (WLMs) in a commercial weight management program.

METHODS

Participants were 4,786 WLMs in WW (formerly Weight Watchers, New York, New York) who had maintained weight loss  ≥ 9.1 kg (24.7 kg/23.8% weight loss on average) for 3.3 years and had a current mean BMI of 27.6 kg/m² . A control group of 528 weight-stable individuals with obesity had a mean BMI of 38.9 kg/m² and weight change  < 2.3 kg over the previous 5 years.

RESULTS

WLMs versus Controls practiced more frequent healthy dietary choices (3.3 vs. 1.9; η p 2  = 0.37), self-monitoring (2.6 vs. 0.7; η p 2  = 0.30), and psychological coping (2.5 vs. 1.1; η p 2  = 0.25) strategies. WLMs also reported more willingness to ignore food cravings (4.4 vs. 3.5; η p 2  = 0.16) and had greater habit strength for healthy eating (5.3 vs. 3.2;  η p 2  = 0.21). Standard canonical coefficients indicated that dietary (0.52), self-monitoring (0.40), and psychological (0.14) strategies as well as habit strength for healthy eating (0.15) contributed independently and most (49.5% of variance) to discriminating groups.

CONCLUSIONS

In a widely available weight management program, more frequent practice of healthy dietary, self-monitoring, and psychological coping strategies as well as development of greater habit strength for healthy eating differentiated long-term WLMs from weight-stable individuals with obesity.

Weight Gain Over 6 Years in Young Adults: The Study of Novel Approaches to Weight Gain Prevention Randomized Trial

OBJECTIVE

The study objective was to determine whether two self-regulation interventions that reduced 3-year weight gain in young adults remain effective at 6 years.

METHODS

A randomized trial was conducted in two academic settings in 599 young adults, aged 18 to 35 years, with normal weight or overweight; 504 (84%) reconsented for a 6-year extension (Study of Novel Approaches to Weight Gain Prevention-Extended [SNAP-E]) with ongoing intervention and assessments. Weight gain over 6 years was compared for all assigned to Control, Large Changes (LC; lose 5-10 pounds initially), and Small Changes (SC; make small daily changes in intake and activity).

RESULTS

Weight change from baseline to 6 years did not differ significantly among the three groups (Control = 3.9 kg, SC = 4.1 kg, and LC = 2.8 kg). However, there was a significant age-by-treatment interaction (P = 0.002). Among those < 25 years old, weight gain from baseline to 6 years averaged 7.3 kg in the Control group and was reduced by almost 50% in LC and SC. LC also significantly reduced mean weight gain (area under the curve) over 6 years compared with Control or SC.

CONCLUSIONS

Although the interventions did not reduce weight gain at 6 years for the full cohort, they were effective in those < 25 years old. Future efforts should focus on young adults aged 18 to 24.9 and test more intensive interventions with more diverse participants.

Long-term Weight Loss Maintenance in the Continuation of a Randomized Diabetes Prevention Translational Study: The Healthy Living Partnerships to Prevent Diabetes (HELP PD) Continuation Trial

OBJECTIVE

HELP PD was a clinical trial of 301 adults with prediabetes. Participants were randomized to enhanced usual care (EUC) or to a lifestyle weight loss (LWL) intervention led by community health workers that consisted of a 6-month intensive phase (phase 1) and 18 months of maintenance (phase 2). At 24 months, participants were asked to enroll in phase 3 to assess whether continued group maintenance (GM) sessions would maintain improvements realized in phases 1 and 2 compared with self-directed maintenance (SM) or EUC.

RESEARCH DESIGN AND METHODS

In phase 3, LWL participants were randomly assigned to GM or SM. EUC participants remained in the EUC arm and, along with participants in SM, received monthly newsletters. All participants received semiannual dietitian sessions. Anthropometrics and biomarkers were assessed every 6 months. Mixed-effects models were used to assess changes in outcomes over time.

RESULTS

Eighty-two of the 151 intervention participants (54%) agreed to participate in phase 3; 41 were randomized to GM and 41 to SM. Of the 150 EUC participants, 107 (71%) continued. Ninety percent of clinic visits were completed. Over 48 months of additional follow-up, outcomes remained relatively stable in the EUC participants; the GM group was able to maintain body weight, BMI, and waist circumference; and these measures all increased significantly (P < 0.001) in the SM group.

CONCLUSIONS

Participants in the GM arm maintained weight loss achieved in phases 1 and 2, while those in the SM arm regained weight. Because group session attendance by the participants in the GM arm was low, it is unclear what intervention components led to successful weight maintenance.

Do the holidays impact weight and self-weighing behaviour among adults engaged in a behavioural weight loss intervention?

We examined the U.S. holiday period impact on weight gain, self-weighing, and treatment success among adults in a weight loss intervention (N=171). Using electronic scales, body weight and self-weighing frequency were compared by time period [i.e., pre-holiday, holiday (November 15-January 1), post-holiday]. Self-weighing was less frequent during holiday period (p<.01), and longer intervention engagement was associated with weight gain (p<.0001) during this time. Enrollment during holiday period was associated with 2.3% 12-month weight loss. Holiday period enrollment might be beneficial for preventing holiday weight gain and facilitating successful intervention outcomes.

Deconstructing Weight Management Interventions for Young Adults: Looking Inside the Black Box of the EARLY Consortium Trials

OBJECTIVE

The goal of the present study was to deconstruct the 17 treatment arms used in the Early Adult Reduction of weight through LifestYle (EARLY) weight management trials.

METHODS

Intervention materials were coded to reflect behavioral domains and behavior change techniques (BCTs) within those domains planned for each treatment arm. The analytical hierarchy process was employed to determine an emphasis profile of domains in each intervention.

RESULTS

The intervention arms used BCTs from all of the 16 domains, with an average of 29.3 BCTs per intervention arm. All 12 of the interventions included BCTs from the six domains of Goals and Planning, Feedback and Monitoring, Social Support, Shaping Knowledge, Natural Consequences, and Comparison of Outcomes; 11 of the 12 interventions shared 15 BCTs in common across those six domains.

CONCLUSIONS

Weight management interventions are complex. The shared set of BCTs used in the EARLY trials may represent a core intervention that could be studied to determine the required emphases of BCTs and whether additional BCTs add to or detract from efficacy. Deconstructing interventions will aid in reproducibility and understanding of active ingredients.

Compensation for cold-induced thermogenesis during weight loss maintenance and regain

Prevalence of obesity is exacerbated by low rates of successful long-term weight loss maintenance (WLM). In part, relapse from WLM to obesity is due to a reduction in energy expenditure (EE) that persists throughout WLM and relapse. Thus, interventions that increase EE might facilitate WLM. In obese mice that were calorically restricted to reduce body weight by ~20%, we manipulated EE throughout WLM and early relapse using intermittent cold exposure (ICE; 4°C, 90 min/day, 5 days/wk, within the last 3 h of the light cycle). EE, energy intake, and spontaneous physical activity were measured during the obese, WLM, and relapse phases. During WLM and relapse, the ICE group expended more energy during the light cycle because of cold exposure but expended less energy in the dark cycle, which led to no overall difference in total daily EE. The compensation in EE appeared to be mediated by activity, whereby the ICE group was more active during the light cycle because of cold exposure but less active during the dark cycle, which led to no overall effect on total daily activity during WLM and relapse. In brown adipose tissue of relapsing mice, the ICE group had greater mRNA expression of Dio2 and protein expression of UCP1 but lower mRNA expression of Prdm16. In summary, these findings indicate that despite robust increases in EE during cold exposures, ICE is unable to alter total daily EE during WLM or early relapse, likely due to compensatory behaviors in activity.

Accuracy of Self-Report Versus Objective Smart-Scale Weights During a 12-Week Weight Management Intervention

OBJECTIVE

Greater frequency of self-weighing has been associated with greater weight loss in weight management interventions, but little is known regarding the accuracy of self-reported weight data.

METHODS

Agreement between objective smart-scale and self-reported weight data was assessed in 74 adults (age = 50.7 years; BMI = 31.2 kg/m² ) enrolled in a 12-week, Internet-based weight management program. Participants were asked to self-weight daily using a study-provided smart scale and to self-report weights via the study website.

RESULTS

There was strong agreement between smart-scale and self-reported weight values (intraclass correlation = 0.982) but only moderate agreement regarding frequency of self-weighing assessed via each method (κ = 0.491; P < 0.0001). Greater self-weighing frequency was associated with greater weight loss across measures (all P < 0.001). Compared with days when participants did both, weights were 0.66 kg higher on days when participants self-weighed via the smart scale but did not self-report weight (8% of days) and 0.58 kg higher on days when they self-reported weight but did not self-weigh via the smart scale (4% of days; all P < 0.0001).

CONCLUSIONS

Results suggest that self-reported weight values are similar to smart-scale measurements; however, either method alone may underestimate self-weighing frequency. Furthermore, missing self-weighing data should not be treated as ignorable because weights may be higher than those observed on nonmissing days.

Long and Short of It: Early Response Predicts Longer-Term Outcomes in Pediatric Weight Management

OBJECTIVE

This study aimed to examine whether 1-month BMI improvement is predictive of superior 6- and 12-month BMI changes in a national sample of youth in pediatric weight management treatment.

METHODS

Participants were 4- to 18-year-olds from the Pediatric Obesity Weight Evaluation Registry, a prospective study collecting data from 31 pediatric weight management programs across the United States. Response at 1 month was defined as ≥ 3% BMI reduction; success at 6 and 12 months was defined as ≥ 5% BMI reduction from baseline. Analyses used linear and logistic regression with robust variance estimation.

RESULTS

Primary analyses were completed with 687 participants (mean age 12.2 years). One-month responders demonstrated significant improvements in BMI compared with nonresponders at 6 months (BMI, -2.05 vs. 0.05; %BMI, -5.81 vs. 0.23; P < 0.001 for all) and 12 months (BMI, -1.87 vs. 0.30; %BMI, -5.04 vs. 1.06; P < 0.001 for all). The odds of success for 1-month responders were 9.64 (95% CI: 5.85-15.87; P < 0.001) times that of nonresponders at 6 months and 5.24 (95% CI: 2.49-11.02; P < 0.001) times that of nonresponders at 12 months.

CONCLUSIONS

In treatment-seeking youth with obesity, early BMI reduction was significantly associated with greater long-term BMI reduction. Nonresponders may benefit from early treatment redirection or intensification.

Dietary and Lifestyle Factors Serve as Predictors of Successful Weight Loss Maintenance Postbariatric Surgery

Bariatric surgery is considered to be an effective treatment for the resolution of severe obesity; however, in more than half of the bariatric surgery patients, weight reacquisition occurs as early as 18 months postsurgery, compromising the surgery's beneficial effects. Maintaining weight loss after surgery poses a great challenge, necessitating the identification of predicting factors. In the present study, we explored the association between weight regain and dietary habits and behavioral lifestyle practices in patients following bariatric surgery. Fifty patients who underwent bariatric surgery with ≥18-month postoperative period of follow-up were included. They were classified into two groups: weight maintainers (n = 29) were patients who regained <15% of their weight, and weight regainers (n = 21) were patients who regained ≥15% of their weight compared to their lowest postoperative weight. The mean age of the study participants was 41.4 ± 8.9 years, and twenty-eight patients (56%) of the total, were females. A detailed analysis of dietary and lifestyle habits was performed by questionnaire-based interviews. Significant weight regain was noted in the regainers compared to the maintainers (19.6 ± 8.4 kg vs. 4.5 ± 3.5 kg, respectively, P ≤ 0.001), which was attributed to their following of unhealthy dietary habits and behavioral lifestyle practices. The dietary and behavioral lifestyle practices adopted by the maintainers were higher fiber consumption and water intake, monitored pace of eating, evasion of emotional binge, and distracted eating and following of self-assessment behaviors. Additionally, regular nutritional follow-ups and compliance with postoperative dietary counseling significantly helped to improve weight maintenance. In conclusion, the effectiveness of weight loss postbariatric surgery was compromised by weight regain due to unhealthy dietary and behavioral lifestyle practices stemming from a lack of nutritional guidance and knowledge. The implementation of comprehensive nutritional counseling and advice on behavioral changes before and after surgery will help achieve optimal weight results.

An Integrated Understanding of the Molecular Mechanisms of How Adipose Tissue Metabolism Affects Long-term Body Weight Maintenance

Lifestyle-based weight loss interventions frequently demonstrate long-term inefficiency and weight regain. Identification of underlying mechanisms and predictors to identify subjects who will benefit from lifestyle-based weight loss strategies is urgently required. We analyzed 143 adults of the randomized Maintain trial (Maintain-Adults) after intended weight loss to identify mechanisms contributing to the regulation of body weight maintenance. Unbiased RNA sequencing of adipose and skeletal muscle biopsies revealed fatty acid metabolism as a key pathway modified by weight loss. Variability of key enzymes of this pathway, estimates of substrate oxidation, and specific serum acylcarnitine (AC) species, representing a systemic snapshot of in vivo substrate flux, predicted body weight maintenance (defined as continuous or dichotomized [< or ≥3% weight regain] variable) 18 months after intended weight loss in the entire cohort. Key results were confirmed in a similar randomized controlled trial in 137 children and adolescents (Maintain-Children), which investigated the same paradigm in a pediatric cohort. These data suggest that adaption of lipid utilization in response to negative energy balance contributes to subsequent weight maintenance. Particularly a functional role for circulating ACs, which have been suggested to reflect intracellular substrate utilization, as mediators between peripheral energy stores and control of long-term energy homeostasis was indicated.

Dietary, physical activity, and weight management interventions among active-duty military personnel: a systematic review

BACKGROUND

Research has been conducted to assess the effectiveness of weight management, dietary and physical activity interventions in military settings. However, a recent and comprehensive overview is lacking. The aim of this systematic review is to examine the evidence and describe key components of effective interventions in terms of improving body composition, dietary behaviors, and physical activity among active-duty military personnel.

METHODS

PubMed, PsycInfo, and CINAHL were searched on the 17th of November 2017 to identify interventions that promoted diet and/or physical activity among active-duty military personnel. Studies were included if they assessed outcomes related to anthropometric measurements, dietary behaviors, or fitness/physical activity levels. There were no restrictions regarding publication date, follow-up duration, and sex. After screening, a total of 136 studies were eligible. Of these studies, 38 included an educational and/or behavioral change component, and 98 had only physical or fitness training as part of basic military training. Only studies that included an educational and/or behavioral change component were assessed for quality using the Effective Public Health Practice Project tool and included in the qualitative synthesis of the results.

RESULTS

Based on consistent evidence from studies that were rated as moderate or strong, there is good evidence that military weight management interventions are effective in improving body composition for durations of up to 12 months. Effective interventions are more likely to be high intensity (have a greater number of sessions), are more often delivered by specialists, and use theoretical base/behavioral change techniques and a standardized guideline. Dietary interventions can potentially reduce total fat and saturated fat intake. Dietary interventions that target the kitchen staff and/or increase the availability of healthy food are more likely to be effective in the short term. The results regarding military physical fitness interventions were inconclusive.

CONCLUSION

Despite limitations such as the diversity and heterogeneity of the included interventions, outcome measurements, and follow-up duration, this systematic review found good evidence that weight management interventions are effective, especially in terms of weight loss. More studies are needed to acquire solid evidence for effectiveness for durations longer than 12 months and to identify key components of the effective dietary and physical activity educational and/or behavioral change interventions, especially in countries outside Europe and the US.

Student midwives' intention to deliver weight management interventions: A theory of planned behaviour & self-determination theory approach

OBJECTIVES

Overweight and obesity during pregnancy is a risk to the health of mother and child. Midwives can modify this key risk factor by providing weight management interventions to women before and during pregnancy. This study investigated social cognitive determinants of pre-clinical student midwives' intention to provide weight management intervention in preconception and antenatal clinical contexts. Social cognitive determinants from the theory of planned behaviour (attitudes, subjective norms, perceived behavioural control) and self-determination theory (autonomous motivation) were used to predict pre-clinical students' intentions once they enter practice.

METHOD

The sample was 183 female pre-clinical student midwives from 17 Australian universities (age range = 18-54 years). Participants received a cross-sectional questionnaire that measured demographic items, attitudes, subjective norms, perceived behavioural control and autonomous motivation towards providing weight management intervention at two different stages of pregnancy - preconception and antenatal.

RESULTS

Attitudes, subjective norms, and perceived behavioural control accounted for 56% of intention to provide weight management interventions to women planning pregnancy; however, the addition of autonomous motivation was non-significant. In contrast, attitudes and subjective norms (but not perceived behavioural control) accounted for 39% of intention to provide weight management interventions to women during pregnancy. Furthermore, the addition of autonomous motivation to the model was significant and accounted for an additional 3.1% of variance being explained.

IMPLICATIONS AND CONCLUSIONS

Curriculum changes that support and increase pre-clinical student midwives' intention should focus on these specific correlates of intention in order to foster long term changes in clinical practice. Changes to the education and training of midwives should be carefully considered to understand their impact on these important determinants of intention to engage in this critical clinical skill.

A Review of the Evidence Surrounding the Effects of Breakfast Consumption on Mechanisms of Weight Management

The recommendation to eat breakfast has received scrutiny due to insufficient causal evidence for improvements in weight management. Despite the limited number of randomized controlled trials examining the effects of breakfast consumption compared with skipping breakfast on weight loss, an increasing number of studies target the hormonal and behavioral mechanisms underlying weight management. This review provides a comprehensive examination of the intervention-based clinical trials that test whether breakfast consumption improves appetite control and satiety as well as energy expenditure compared with skipping breakfast. Several factors were considered when interpreting the body of evidence. These include, but were not limited to, the following: the composition of breakfast, with a specific focus on dietary protein; meal size and form; and habitual breakfast behaviors. The evidence within this review shows positive to neutral support for the inclusion of breakfast for improvements in appetite control, satiety, and postprandial energy expenditure. The protein content, energy content, and form of the meal (i.e., beverages compared with foods) are key modulating factors for ingestive behavior and energy expenditure mechanisms. Specifically, breakfast meals containing a larger amount of protein (≥30 g protein/meal) and energy (≥350 kcal/meal) and provided as solid foods increased the magnitude of the appetite and satiety response compared with breakfast skipping. Longer-term randomized controlled trials including the measurement of ingestive behavior and weight management are needed to identify the role of breakfast for health promotion.

Personality Traits Associated with Weight Maintenance among Successful Weight Losers

Objective The influence of personality traits on successful weight loss has been studied previously with conflicting findings. Much less is known about the influence of personality traits on weight maintenance after weight loss. The aims of this study were to assess how personality traits were associated with motivational factors, dietary habits, self-weighing frequency, need for support, and difficulties encountered during the weight loss process in formerly successful weight maintainers. MethodsThis study was based upon findings from the Finnish Weight Control Registry, including 158 (100 women and 58 men, age 18-60 years) formerly obese participants with ≥10% weight loss and who maintained it ≥ 2 years. Data were collected through electronic forms and personality traits were assessed according to the Five Factor Model with the Finnish version of the Ten Item Personality Inventory. ResultsPersonality traits neuroticism, agreeableness, and conscientiousness were associated with motivational factors, self-weighing frequency, dietary habits, support, and difficulties during the weight loss process. Sex differences were observed. ConclusionsPersonality traits may be important in successful long-term weight maintenance after weight loss. Our results might not be generalizable in other populations because only Caucasians were included. The small sample size needs to be considered.

Physical activity and weight maintenance: the utility of wearable devices and mobile health technology in research and clinical settings

PURPOSE OF REVIEW

The integration of wearable devices and mobile health (mHealth) technology to facilitate behavior change has the potential to transform the efficacy of interventions and implementation programs for weight maintenance. The purpose of this review was to provide a comprehensive analysis of the overall utility of wearable devices for assessing and promoting weight maintenance in research and clinical settings.

RECENT FINDINGS

Recent intervention trials using wearable devices have been successful in increasing physical activity and decreasing or maintaining body weight, but complex study designs involving multiple behavioral strategies make it difficult to assess whether wearable devices can independently influence weight status. The daily feedback that wearable devices and mHealth technology provide may assist in motivating higher levels of physical activity achievement. However, the integration of wearable devices into the healthcare setting and implementation of mHealth programs still need to be tested.

SUMMARY

Recent studies add concrete implications for providers and researchers to better assess and promote physical activity in healthcare settings by identifying how wearable devices can be advantageous for physical activity and health promotion.

Effects of a combined dietary, exercise and behavioral intervention and sympathetic system on body weight maintenance after intended weight loss: Results of a randomized controlled trial

BACKGROUND

Lifestyle based weight loss interventions are hampered by long-term inefficacy. Prediction of individuals successfully reducing body weight would be highly desirable. Although sympathetic activity is known to contribute to energy homeostasis, its predictive role in body weight maintenance has not yet been addressed.

OBJECTIVES

We investigated, whether weight regain could be modified by a weight maintenance intervention and analyzed the predictive role of weight loss-induced changes of the sympathetic system on long-term weight regain.

DESIGN

156 subjects (age > 18; BMI ≥ 27 kg/m²) participated in a 12-week weight reduction program. After weight loss (T0), 143 subjects (weight loss > 8%) were randomized to a 12-month lifestyle intervention or a control group. After 12 months (T12) no further intervention was performed until month 18 (T18). Weight regain at T18 (regain_BMI) was the primary outcome. Evaluation of systemic and tissue specific estimates of sympathetic system was a pre-defined secondary outcome.

RESULTS

BMI was reduced by 4.67 ± 1.47 kg/m² during the initial weight loss period. BMI maintained low in subjects of the intervention group until T12 (+0.07 ± 2.98 kg/m²; p = 0.58 compared to T0), while control subjects regained +0.98 ± 1.93 kg/m² (p < 0.001 compared to T0). The intervention group regained more weight than controls after ceasing the intervention (1.17 ± 1.34 vs. 0.57 ± 0.93 kg/m²) until T18. Consequently, BMI was not different at T18 (33.49 (32.64; 34.33) vs. 34.18 (33.61; 34.75) kg/m²; p=0.17). Weight loss-induced modification of urinary metanephrine excretion independently predicted regain_BMI (R² = 0.138; p < 0.05). The lifestyle intervention did not modify the course of urinary metanephrines after initial weight loss.

CONCLUSIONS

Our lifestyle intervention successfully maintained body weight during the intervention period. However, no long-term effect could be observed beyond the intervention period. Predictive sympathetic activity was not persistently modified by the intervention, which may partially explain the lack of long-term success of such interventions.

Neural Food Reward Processing in Successful and Unsuccessful Weight Maintenance

OBJECTIVE

Weight loss maintenance is one of the biggest challenges in behavioral weight loss programs. The present study aimed to examine metabolic influences on the mesolimbic reward system in people with successful and unsuccessful long-term weight loss maintenance.

METHODS

Thirty-three women with obesity at least 6 months after the completion of a diet were recruited: seventeen women were able to maintain their weight loss, whereas sixteen showed weight regain. Using functional magnetic resonance imaging in combination with the assessment of appetite-regulating hormones, neural reward processing during hunger and satiety was investigated. An incentive delay task was employed to investigate the expectation and receipt of both food-related and monetary reward.

RESULTS

Only participants with successful weight loss maintenance showed a satiety-induced attenuation of brain activation during the receipt of a food-related reward. Furthermore, in successful weight loss maintenance, the attenuation of active ghrelin levels was related to brain activation in response to food-related reward anticipation during satiety.

CONCLUSIONS

The findings suggest that an attenuated influence of satiety signaling on the neural processing of food-related reward contributes to unsuccessful weight loss maintenance. Thus, intact satiety signaling to the mesolimbic reward system may serve as a promising target for tackling weight cycling.

Nonnutritive Sweeteners in Weight Management and Chronic Disease: A Review

OBJECTIVE

The objective of this review was to critically review findings from recent studies evaluating the effects of nonnutritive sweeteners (NNSs) on metabolism, weight, and obesity-related chronic diseases. Biologic mechanisms that may explain NNS effects will also be addressed.

METHODS

A comprehensive review of the relevant scientific literature was conducted.

RESULTS

Most cross-sectional and prospective cohort studies report positive associations between NNS consumption, body weight, and health conditions, including type 2 diabetes, cardiovascular disease, and nonalcoholic fatty liver disease. Although findings in cellular and rodent models suggest that NNSs have harmful effects on metabolic health, most randomized controlled trials in humans demonstrate marginal benefits of NNS use on body weight, with little data available on other metabolic outcomes.

CONCLUSIONS

NNS consumption is associated with higher body weight and metabolic disease in observational studies. In contrast, randomized controlled trials demonstrate that NNSs may support weight loss, particularly when used alongside behavioral weight loss support. Additional long-term, well-controlled intervention studies in humans are needed to determine the effects of NNSs on weight, adiposity, and chronic disease under free-living conditions.

Significant improvement in cardiometabolic health in healthy nonobese individuals during caloric restriction-induced weight loss and weight loss maintenance

Calorie restriction (CR) triggers benefits for healthspan including decreased risk of cardiometabolic disease (CVD). In an ancillary study to CALERIE 2, a 24-mo 25% CR study, we assessed the cardiometabolic effects of CR in 53 healthy, nonobese (BMI: 22-28 kg/m2) men ( n = 17) and women ( n = 36). The aim of this study was to investigate whether CR can reduce risk factors for CVD and insulin resistance in nonobese humans and, moreover, to assess whether improvements are exclusive to a period of weight loss or continue during weight maintenance. According to the energy balance method, the 25% CR intervention ( n = 34) produced 16.5 ± 1.5% (mean ± SE) and 14.8 ± 1.5% CR after 12 and 24 mo (M12, M24), resulting in significant weight loss (M12 -9 ± 0.5 kg, M24 -9 ± 0.5 kg, P < 0.001). Weight was maintained in the group that continued their habitual diet ad libitum (AL, n = 19). In comparison to AL, 24 mo of CR decreased visceral (-0.5 ± 0.01 kg, P < 0.0001) and subcutaneous abdominal adipose tissue (-1.9 ± 0.2kg, P < 0.001) as well as intramyocellular lipid content (-0.11 ± 0.05%, P = 0.031). Furthermore, CR decreased blood pressure (SBP -8 ± 3 mmHg, P = 0.005; DBP -6 ± 2 mmHg, P < 0.001), total cholesterol (-13.6 ± 5.3 mg/dl, P = 0.001), and LDL-cholesterol (-12.9 ± 4.4 mg/dl, P = 0.005), and the 10-yr risk of CVD-disease was reduced by 30%. Homeostasis model assessment of insulin resistance (HOMA-IR) decreased during weight loss in the CR group (-0.46 ± 0.15, P = 0.003), but this decrease was not maintained during weight maintenance (-0.11 ± 0.15, P = 0.458). In conclusion, sustained CR in healthy, nonobese individuals is beneficial in improving risk factors for cardiovascular and metabolic disease such as visceral adipose tissue mass, ectopic lipid accumulation, blood pressure, and lipid profile, whereas improvements in insulin sensitivity were only transient.

An Examination of How People Who Have Lost Weight Communicatively Negotiate Interpersonal Challenges to Weight Management

The vast majority of Americans are overweight, and those who are able to lose weight typically regain at least the amount they lost. Some people are confronted with sabotage, criticism, and declines in social support during and following weight loss. However, how individuals negotiate these interpersonal barriers is not very well understood. Such an understanding could help individuals maintain their weight loss while minimizing the risk of adverse health or relational consequences. Thus, through a thematic analysis of 40 interviews of people who were identified as previously overweight or obese and a facework lens (Cupach & Metts, 1994; Goffman, 1967), this study examined how people were communicatively able to sustain their weight loss in the face of challenges from friends, family, and colleagues. The investigation found that altered weight management behaviors (particularly healthy eating) can threaten others' face and uncovered several communication strategies people used to prevent and mitigate face threat. To avoid face threat, participants proactively issued cognitive disclaimers about weight management or designated cheat days, accepted but did not consume food, avoided social situations involving food, or ate unhealthy food in smaller portions to assimilate with the in-group. To remediate face threat, participants provided personal choice and health excuses to save face and accomplish their dual goals of maintaining their weight management practices without compromising their relationships.

Partial Sleep Deprivation Reduces the Efficacy of Orexin-A to Stimulate Physical Activity and Energy Expenditure

OBJECTIVE

Sufficient sleep is required for weight maintenance. Sleep deprivation due to noise exposure stimulates weight gain by increasing hyperphagia and reducing energy expenditure (EE). Yet the mechanistic basis underlying the weight gain response is unclear. Orexin-A promotes arousal and negative energy balance, and orexin terminals project to the ventrolateral preoptic area (VLPO), which is involved in sleep-to-wake transitions. To determine whether sleep deprivation reduces orexin function in VLPO and to test the hypothesis that sleep deprivation would attenuate the orexin-A-stimulated increase in arousal, physical activity (PA), and EE.

METHODS

Electroencephalogram, electromyogram, distance traveled, and EE were determined in male Sprague-Dawley rats following orexin-A injections into VLPO both before and after acute (12-h) and chronic (8 h/d, 9 d) sleep deprivation by noise exposure.

RESULTS

Orexin-A in the VLPO significantly increased arousal, PA, total EE, and PA-related EE and reduced sleep and respiratory quotient before sleep deprivation. In contrast to after acute sleep deprivation in which orexin-A failed to stimulate EE during PA only, orexin-A failed to significantly increase arousal, PA, fat oxidation, total EE, and PA-related EE after chronic sleep deprivation.

CONCLUSIONS

Sleep deprivation may reduce sensitivity to endogenous stimuli that enhance EE due to PA and thus stimulate weight gain.

Cardiorespiratory benefits of group exercise among adults with serious mental illness

This study examined cardiorespiratory fitness (CRF) among adults with serious mental illness (SMI) participating in group exercise classes. Overweight and obese adults with SMI were randomized to either a control condition or a weight management condition with group exercise classes (n = 222). Submaximal bicycle ergometry was used to assess CRF at baseline, 6 and 18 months. Those with ≥ 66% participation in the exercise classes had a lower heart rate response at 6 and 18 month follow-up. Participation in group exercise classes was associated with improved short and long term cardiovascular fitness among adults with SMI.

Behavioral and Psychological Phenotyping of Physical Activity and Sedentary Behavior: Implications for Weight Management

OBJECTIVE

Risk for obesity is determined by a complex mix of genetics and lifetime exposures at multiple levels, from the metabolic milieu to psychosocial and environmental influences. These phenotypic differences underlie the variability in risk for obesity and response to weight management interventions, including differences in physical activity and sedentary behavior.

METHODS

As part of a broader effort focused on behavioral and psychological phenotyping in obesity research, the National Institutes of Health convened a multidisciplinary workshop to explore the state of the science in behavioral and psychological phenotyping in humans to explain individual differences in physical activity, both as a risk factor for obesity development and in response to activity-enhancing interventions.

RESULTS

Understanding the behavioral and psychological phenotypes that contribute to differences in physical activity and sedentary behavior could allow for improved treatment matching and inform new targets for tailored, innovative, and effective weight management interventions.

CONCLUSIONS

This summary provides the rationale for identifying psychological and behavioral phenotypes relevant to physical activity and identifies opportunities for future research to better understand, define, measure, and validate putative phenotypic factors and characterize emerging phenotypes that are empirically associated with initiation of physical activity, response to intervention, and sustained changes in physical activity.

Modifiable risk factors of maternal postpartum weight retention: an analysis of their combined impact and potential opportunities for prevention

BACKGROUND/OBJECTIVES

Pregnancy triggers a physiological change in weight status. Postpartum weight retention in the childbearing years can substantially alter a woman's weight gain trajectory, with several potential contributing factors identified. Most research has relied on women's recall of pre-pregnancy weight during pregnancy or later, and not considered risk factors in combination. Using measured pre-pregnancy weight, this study aimed to examine the associations of maternal postpartum weight retention with parity, pre-pregnancy BMI, excessive gestational weight gain (GWG), maternal serum vitamin D concentration and dietary Glycaemic Index in early and late pregnancy, and breastfeeding duration, including analysis of the combined impact of potentially modifiable risk factors.

SUBJECTS/METHODS

Prospective cohort study of 12 583 non-pregnant women aged 20-34 years in Southampton (UK) who were assessed prior to pregnancy, with those who subsequently became pregnant followed up in early and late gestation, and after delivery (n=2559 in the final sample). Linear regression models examined potential predictors of weight retention in adjusted individual and multivariate analyses, and as a risk factor score.

RESULTS

Compared with pre-pregnancy weight, 73% of women retained some weight at 6 months postpartum (mean (s.d.): 3.5 (6.2) kg). In the adjusted multivariate model, women who were primiparous, had a lower pre-pregnancy BMI, excessive GWG, a lower early pregnancy vitamin D concentration and breastfed for <6 months had greater weight retention 6 months postpartum (P<0.05 for all variables). For each additional modifiable risk factor (excessive GWG, low vitamin D concentration in early pregnancy and short breastfeeding duration; scale 0-3), women retained an additional 2.49 kg (95% CI: 2.16, 2.82; P<0.001).

CONCLUSIONS

Having a greater number of modifiable risk factors was associated with greater weight retention 6 months postpartum. Initiatives supporting women to target these risk factors in the years prior to, during and after pregnancy could impact on their weight gain trajectory and later risk of adverse weight-related outcomes.

Establishing energy requirements for body weight maintenance: validation of an intake-balance method

BACKGROUND

Experimentally establishing a group's body weight maintenance energy requirement is an important component of metabolism research. At present, the reference approach for measuring the metabolizable energy intake (MEI) from foods required for body weight maintenance in non-confined subjects is the doubly-labeled water (DLW)-total energy expenditure (TEE) method. In the current study, we evaluated an energy-intake weight balance method as an alternative to DLW that is more flexible and practical to apply in some settings.

METHODS

The hypothesis was tested that MEI from foods observed in a group of subjects maintaining a constant energy intake while keeping their weight within ±1 kg over 10 days is non-significantly different from DLW-measured TEE (TEEDLW). Six non-obese subjects evaluated as part of an earlier study completed the inpatient protocol that included a 3-day initial adjustment period.

RESULTS

The group body weight coefficient of variation (X ± SD) during the 10-day balance period was 0.38 ± 0.10% and the slope of the regression line for body weight versus protocol day was non-significant at 1.8 g/day (R2, 0.002, p = 0.98). MEI from foods observed during the 10-day balance period (2390 ± 543 kcal/day) was non-significantly different (p = 0.96) from TEE measured by DLW (2373 ± 713 kcal/day); the MEI/TEEDLW ratio was 1.03 ± 0.15 (range 0.87-1.27) and the correlation between MEI from foods and TEEDLW was highly significant (R2, 0.88, p = 0.005).

CONCLUSIONS

A carefully managed 10-day protocol that includes a constant MEI level from foods with weight stability (±1 kg) will provide a group's body weight maintenance energy requirement similar to that obtained with DLW. This approach opens the possibility of conducting affordable weight balance studies, shorter in duration than those previously reported, that are needed to answer a wide range of questions in clinical nutrition. Trial registration The study is registered at http://www.clinicaltrials.gov (NCT01672632; August 20, 2012).

Obesity and weight management at menopause

BACKGROUND

Many women report gaining weight as they transition through menopause. For most, the weight gain is modest and can be reduced with a conscious effort to limit energy intake and increase energy expenditure. However, many women who are already overweight and obese will gain more weight as they approach menopause.

OBJECTIVE

The aims of this paper are to explain the reasons for menopausal weight gain and to detail a method for achieving and sustaining a substantial weight loss.

DISCUSSION

Weight gain during menopause is predominantly due to a reduction in spontaneous activity. For women who are lean, advice about controlling energy intake and increasing physical activity may be all that is required to prevent weight gain. For women who are overweight and obese rapid weight loss is best achieved with the help of a very low energy diet. This must be followed by lifelong behaviour modification with or without the help of hunger-suppressing pharmacotherapy.

Before, after, & after-after: Clinical implications of weight loss recidivism

Weight recovery among obese patients who have lost weight through lifestyle modification or bariatric surgery is a common clinical challenge that often leads to patient stigmatization and unexpected health problems. A review of the literature describes how weight loss alters energy homeostasis to limit weight loss and restore lost fat mass in patients who have successfully lost weight.

Priorities and Preferences for Weight Management and Cardiovascular Risk Reduction in Primary Care

Implementing behavioral interventions for cardiovascular risk reduction and weight management is challenging in primary care. Primary care patients and providers were recruited for qualitative interviews to identify priorities and preferences for addressing weight management. Thematic analysis was used to identify relevant resources, barriers to lifestyle modification, health behavior change, and implementation of weight management strategies into care. Patients and providers prioritized increasing physical activity and healthy diets when managing chronic disease; and reported decreased patient motivation, knowledge, and limited organizational capacity and time among providers to deliver intensive interventions. Providers and patients disagreed regarding who owns accountability for weight management.

Long-Term Weight Maintenance Strategies Are Experienced as a Burden by Persons Who Have Lost Weight Compared to Persons with a lifetime Normal, Stable Weight

OBJECTIVE

To assess dietary intake, eating patterns, physical activity and eating behaviors, and to explore strategies and perceptions of the experience of weight maintenance in weight loss maintainers (weight loss maintenance (WLM) ≥ 10% weight loss maintained for ≥1 year) and in matched controls with a lifetime stable normal weight.

METHODS

Volunteers (32) were recruited by a snowball procedure in this cross-sectional, mixed-methods study. Diet, physical activity, and eating behaviors were assessed with validated questionnaires. Strategies and experiences were investigated during interviews. Descriptive coding, thematic analysis (qualitative data) as well as descriptive analysis and t-tests (quantitative data) were performed.

RESULTS

Both groups had similar energy and macronutrient consumption. Those in the WLM group reported higher levels of exercise and scored higher on several dimensions of eating disorders. Four themes - 'food choices,' 'quantities and portion control,' 'physical activity', and 'burden' - emerged from the qualitative data. Both groups used similar weight maintenance strategies, but those in the WLM group experienced a higher burden, expressing effortful control which contrasted with the control group's confidence in their internal cues.

CONCLUSION

Our results show an additional burden related with maintaining weight loss compared to keeping a stable normal weight. They provide evidence to devise interventions that will address the difficulty of regulating intake.

Macronutrient Content of the Diet: What Do We Know About Energy Balance and Weight Maintenance?

The 2013 AHA/ACC Clinical Guideline for the Management of Overweight and Obesity recommends a reduced energy diet for weight loss regardless of the macronutrient content. However, diet composition may affect the maintenance of weight loss. In general, a healthful dietary pattern with reduced portion sizes, low energy dense foods, and physical activity are successful for many. Certain populations, such as those with insulin resistance, may find reductions in carbohydrate and higher levels of unsaturated fats to be more effective and promote greater adherence. Of importance is that metabolic adaptations following weight loss also may impact weight loss maintenance and should be considered in the transition from weight loss to weight stabilization. Thus, weight loss and weight maintenance strategies are both important in an intervention for sustaining long-term behavior change.

Beneficial Effects of a Dietary Weight Loss Intervention on Human Gut Microbiome Diversity and Metabolism Are Not Sustained during Weight Maintenance

OBJECTIVE

In the present study, we examined the effect of a very low-calorie diet(VLCD)-based obesity program on human gut microbiome diversity and metabolism during weight loss and weight maintenance.

METHODS

Obese subjects underwent 3 months of VLCD followed by 3 months of weight maintenance. A lean and an obese control group were included. The microbiome was characterized by performing high-throughput dual-indexed 16S rDNA amplicon sequencing.

RESULTS

At baseline, a significant difference in the Firmicutes/Bacteroidetes ratio between the lean and obese individuals was observed (p = 0.047). The VLCD resulted in significant alterations in gut microbiome diversity from baseline to 3 months (p = 0.0053). Acinetobacter represented an indicator species for the observed effect (indicator value = 0.998, p = 0.006). Metabolic analyses revealed alterations of the bacterial riboflavin pathway from baseline to 3 months (pnom = 0.0078). These changes in diversity and bacterial metabolism induced by VLCD diminished during the weight maintenance phase, despite sustained reductions in body weight and sustained improvements of insulin sensitivity.

CONCLUSION

The present data show that a VLCD is able to beneficially alter both gut microbiome diversity and metabolism in obese humans, but that these changes are not sustained during weight maintenance. This finding might suggest that the microbiome should be targeted during obesity programs.

What is the Mechanism Behind Weight Loss Maintenance with Gastric Bypass?

Obesity is an epidemic on the rise. With the failure of non-surgical strategies, bariatric surgery has emerged as the most effective therapeutic option for the treatment of severe obesity. Among various surgical options, Roux-en-Y gastric bypass (RYGB) results in sustained weight loss and profound metabolic improvements. The traditional view that gastric bypass and bariatric surgery in general works primarily through restriction/malabsorption of nutrients has become obsolete. It is now increasingly recognised that its mechanisms of action are primarily physiologic, not mechanic. In fact, clinical and translational studies over the last decade have shown that a number of gastrointestinal mechanisms, including changes in gut hormones, neural signalling, intestinal flora, bile acid and lipid metabolism can play a significant role in the effects of this procedure on energy homeostasis. The clinical efficacy and mechanisms of action of RYGB provide a compelling evidence for the role of the gastrointestinal tract in the regulation of appetite and satiety, body weight and glucose metabolism. This review discusses the physiologic changes that occur after RYGB and that contribute to its mechanisms of action.

Middle-aged women's decisions about body weight management: needs assessment and testing of a knowledge translation tool

OBJECTIVE

This study aims to assess middle-aged women's needs when making body weight management decisions and to evaluate a knowledge translation tool for addressing their needs.

METHODS

A mixed-methods study used an interview-guided theory-based survey of professional women aged 40 to 65 years. The tool summarized evidence to address their needs and enabled women to monitor actions taken. Acceptability and usability were reported descriptively.

RESULTS

Sixty female participants had a mean body mass index of 28.0 kg/m(2) (range, 17.0-44.9 kg/m(2)), and half were premenopausal. Common options for losing (82%) or maintaining (18%) weight included increasing physical activity (60%), eating healthier (57%), and getting support (40%). Decision-making involved getting information on options (52%), soliciting others' decisions/advice (20%), and being self-motivated (20%). Preferred information sources included written information (97%), counseling (90%), and social networking websites (43%). Five professionals (dietitian, personal trainer, occupational therapist, and two physicians) had similar responses. Of 53 women sent the tool, 27 provided acceptability feedback. They rated it as good to excellent for information on menopause (96%), body weight changes (85%), and managing body weight (85%). Most would tell others about it (81%). After 4 weeks of use, 25 women reported that the wording made sense (96%) and that the tool had clear instructions (92%) and was easy to use across time (88%). The amount of information was rated as just right (64%), but the tool had limited space for responding (72%).

CONCLUSIONS

When making decisions about body weight management, women's needs were "getting information" and "getting support." The knowledge translation tool was acceptable and usable, but further evaluation is required.