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.

Attitudes to Three Weight Maintenance Strategies: A Qualitative Study.

Weight loss maintenance can be difficult and ultimately unsuccessful, due to psychological, behavioural, social, and physiological influences. The present study investigated three strategies with the potential to improve weight maintenance success: daily weighing, missing an occasional meal, habitually changing high energy foods. The principal aim was to gain an understanding of attitudes to these strategies in participants who had recent experience of weight loss attempts, with or without maintenance. This was a qualitative study involving semi-structured interviews, with 20 participants aged 18-67 (twelve females), analysed using thematic analysis. Most participants disliked daily weighing and missing an occasional meal for long-term maintenance and were concerned about potential negative effects on mental health. All participants had experience of habitual changes to high energy foods and regarded this strategy as obvious and straightforward. Replacement of high energy foods was favoured over elimination. Participants preferred strategies that felt flexible, "normal" and intuitive and disliked those that were thought to have a negative impact on mental health. Further investigation is needed on whether concerns regarding mental health are well founded and, if not, how the strategies can be made more acceptable and useful.

Associations of quantity and quality of carbohydrate sources with subjective appetite sensations during 3-year weight-loss maintenance: Results from the PREVIEW intervention study.

BACKGROUND & AIMS: The association of quantity and quality of carbohydrate sources with appetite during long-term weight-loss maintenance (WLM) after intentional weight loss (WL) is unclear. We aimed to investigate longitudinal associations of quantity and quality of carbohydrate sources with changes in subjective appetite sensations during WLM. METHODS: This secondary analysis evaluated longitudinal data from the 3-year WLM phase of the PREVIEW study, a 2 × 2 factorial (diet-physical activity arms), multi-center, randomized trial. 1279 individuals with overweight or obesity and prediabetes (25-70 years; BMI≥25 kg m-2) were included. Individuals were merged into 1 group to assess longitudinal associations of yearly changes in appetite sensations. Quantity and quality of carbohydrate sources including total carbohydrate, glycemic index (GI), glycemic load (GL), and total dietary fiber were assessed via 4-day food diaries at 4 timepoints (26, 52, 104, and 156 weeks) during WLM. Visual analog scales were used to assess appetite sensations in the previous week. RESULTS: During WLM, participants consumed on average 160.6 (25th, 75th percentiles 131.1, 195.8) g·day-1 of total carbohydrate, with GI 53.8 (48.7, 58.8) and GL 85.3 (67.2, 108.9) g day-1, and 22.3 (17.6, 27.3) g·day-1 of dietary fiber. In the available-case analysis, multivariable-adjusted linear mixed models with repeated measures showed that each 30-g increment in total carbohydrate was associated with increases in hunger (1.36 mm year-1, 95% CI 0.77, 1.95, P < 0.001), desire to eat (1.10 mm year-1, 0.59, 1.60, P < 0.001), desire to eat something sweet (0.99 mm year-1, 0.30, 1.68, P = 0.005), and weight regain (0.20%·year-1, 0.03, 0.36, P = 0.022). Increasing GI was associated with weight regain, but not associated with increases in appetite sensations. Each 20-unit increment in GL was associated with increases in hunger (0.92 mm year-1, 0.33, 1.51, P = 0.002), desire to eat (1.12 mm year-1, 0.62, 1.62, P < 0.001), desire to eat something sweet (1.13 mm year-1, 0.44, 1.81, P < 0.001), and weight regain (0.35%·year-1, 0.18, 0.52, P < 0.001). Surprisingly, dietary fiber was also associated with increases in desire to eat, after adjustment for carbohydrate or GL. CONCLUSIONS: In participants with moderate carbohydrate and dietary fiber intake, and low to moderate GI, we found that higher total carbohydrate, GL, and total fiber, but not GI, were associated with increases in subjective desire to eat or hunger over 3 years. This study was registered as ClinicalTrials.gov, NCT01777893.

Changes in Circulating Metabolites during Weight Loss and Weight Loss Maintenance in Relation to Cardiometabolic Risk.

(1) Background: There is a substantial lack of knowledge of the biochemical mechanisms by which weight loss and weight regain exert their beneficial and adverse effects, respectively, on cardiometabolic outcomes. We examined associations between changes in circulating metabolites and changes in cardiometabolic risk factors during diet-induced weight loss and weight loss maintenance. (2) Methods: This prospective analysis of data from the Satiety Innovation (SATIN) study involved adults living with overweight and obesity (mean age=47.5). One hundred sixty-two subjects achieving ≥8% weight loss during an initial 8-week low-calorie diet (LCD) were included in a 12-week weight loss maintenance period. Circulating metabolites (m=123) were profiled using a targeted multiplatform approach. Data were analyzed using multivariate linear regression models. (3) Results: Decreases in the concentrations of several phosphatidylcholines (PCs), sphingomyelins (SMs), and valine were consistently associated with decreases in total (TChol) and low-density lipoprotein cholesterol (LDL-C) levels during the LCD. Increases in PCs and SMs were significantly associated with increases in TChol and LDL-C during the weight loss maintenance period. Decreases and increases in PCs during LCD and maintenance period, respectively, were associated with decreases in the levels of triglycerides. (4) Conclusions: The results of this study suggest that decreases in circulating PCs and SMs during weight loss and the subsequent weight loss maintenance period may decrease the cardiovascular risk through impacting TChol and LDL-C.

Reverse-translational identification of a cerebellar satiation network.

The brain is the seat of body weight homeostasis. However, our inability to control the increasing prevalence of obesity highlights a need to look beyond canonical feeding pathways to broaden our understanding of body weight control1-3. Here we used a reverse-translational approach to identify and anatomically, molecularly and functionally characterize a neural ensemble that promotes satiation. Unbiased, task-based functional magnetic resonance imaging revealed marked differences in cerebellar responses to food in people with a genetic disorder characterized by insatiable appetite. Transcriptomic analyses in mice revealed molecularly and topographically -distinct neurons in the anterior deep cerebellar nuclei (aDCN) that are activated by feeding or nutrient infusion in the gut. Selective activation of aDCN neurons substantially decreased food intake by reducing meal size without compensatory changes to metabolic rate. We found that aDCN activity terminates food intake by increasing striatal dopamine levels and attenuating the phasic dopamine response to subsequent food consumption. Our study defines a conserved satiation centre that may represent a novel therapeutic target for the management of excessive eating, and underscores the utility of a 'bedside-to-bench' approach for the identification of neural circuits that influence behaviour.

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.

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.

Weight and waist-to-hip ratio change pattern during the first five years of survival: data from a longitudinal observational Chinese breast cancer cohort.

BACKGROUND: Body weight management was an important component in breast cancer survivorship care. The present study described the change patterns of body weight and waist-to-hip ratio (WHR) during the first 5 years of survival, and investigated potential factors associated with very substantial changes. PATIENTS AND METHODS: Based on a longitudinal cohort with 1462 Chinese women with breast cancer, anthropometric measurements including body weight, height, waist and hip circumferences were measured by trained interviewers following standard protocol at four time-points: baseline at study entry, 18-, 36- and 60-months follow up assessments (termed as T0, T1, T2 and T3, respectively). Body height was measured at baseline and body weight at cancer diagnosis were retrieved from medical record. RESULTS: Compared to weight at breast cancer diagnosis, the median weight change was - 0.5 kg, 0 kg, + 0.5 kg, and + 1 kg at T0, T1, T2 and T3, respectively. During the first 5 years of survival, the proportion of women who were obese have slightly increased. At 60-months after diagnosis, only 14.3% of women had weight gain by > 5 kg; and the percentage of women who had weight gain by > 10% was 10.7%. Nearly half of patients had abdominal obesity at study entry, and this proportion were gradually increased to nearly 70% at 60-months follow-up. Multivariate analysis indicated that older age, and frequent sports participation during the first 5 years of survival were related to lower risk of very substantial weight gain (> 10%) at 60-month follow-up; patients aged 40-49 years, having ≥2 comorbidities and ER negative were associated with less likelihood of very substantial WHR substantial increase (> 10%) at 60-month follow-up. CONCLUSION: Weight gain was modest in Chinese breast cancer survivors during the first 5 years of survival, while central adiposity has become a contemporary public health issue. The incorporation of healthy weight and abdominal circumference patient education and management has a potential to improve cancer survivorship.

Weight management and determinants of weight change in patients with coronary artery disease.

OBJECTIVE: To study the effects of a comprehensive secondary prevention programme on weight loss and to identify determinants of weight change in patients with coronary artery disease (CAD). METHODS: We performed a secondary analysis focusing on the subgroup of overweight CAD patients (BMI ≥27 kg/m2) in the Randomised Evaluation of Secondary Prevention by Outpatient Nurse SpEcialists-2 (RESPONSE-2) multicentre randomised trial. We evaluated weight change from baseline to 12-month follow-up; multivariable logistic regression with backward elimination was used to identify determinants of weight change. RESULTS: Intervention patients (n=280) lost significantly more weight than control patients (n=257) (-2.4±7.1 kg vs -0.2±4.6 kg; p<0.001). Individual weight change varied widely, with weight gain (≥1.0 kg) occurring in 36% of interventions versus 41% controls (p=0.21). In the intervention group, weight loss of ≥5% was associated with higher age (OR 2.94), lower educational level (OR 1.91), non-smoking status (OR 2.92), motivation to start with weight loss directly after the baseline visit (OR 2.31) and weight loss programme participation (OR 3.33), whereas weight gain (≥1 kg) was associated with smoking cessation ≤6 months before or during hospitalisation (OR 3.21), non-Caucasian ethnicity (OR 2.77), smoking at baseline (OR 2.70), lower age (<65 years) (OR 1.47) and weight loss programme participation (OR 0.59). CONCLUSION: The comprehensive secondary prevention programme was, on average, effective in achieving weight loss. However, wide variation was observed. As weight gain was observed in over one in three participants in both groups, prevention of weight gain may be as important as attempts to lose weight. TRIAL REGISTRATION NUMBER: NTR3937.

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.

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.

Effects of food stimuli on event-related potentials of restrained eating subgroups during task switching.

Executive functions are thought to affect problematic eating behaviors in restrained eaters. While neurophysiological features of inhibitory control among restrained eaters in particular have been extensively investigated, considerably less is known about its influence on cognitive flexibility. The present study investigated the behavioral and neural correlates of food-related cognitive flexibility with event-related potentials (ERPs) associated in a task-switching paradigm among successful restrained eaters (SREs, n = 30) and unsuccessful restrained eaters (UREs, n = 32). Behavioral results revealed smaller switch reaction times among SREs than among UREs in both food-stimuli and neutral-stimuli tasks. ERP analyses indicated that neutral-switch trials, especially in UREs, displayed larger N2 amplitudes. In addition, SREs displayed larger P3 amplitudes in frontal, frontal-central, and central than UREs. P3 amplitude increased significantly during food-stimuli tasks compared to that during neutral-stimuli tasks. These results indicate that SREs possess better efficiency in enhanced cognitive transformation during the processing of target monitoring and conflict resolution. This is the first study to provide evidence for differences between SREs and UREs during task switching using ERP measures and reliance on different food-related processing strategies among SREs compared to UREs.

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.

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.

Combined analysis of gestational diabetes and maternal weight status from pre-pregnancy through post-delivery in future development of type 2 diabetes.

We examined the associations of gestational diabetes mellitus (GDM) and women's weight status from pre-pregnancy through post-delivery with the risk of developing dysglycaemia [impaired fasting glucose, impaired glucose tolerance, and type 2 diabetes (T2D)] 4-6 years post-delivery. Using Poisson regression with confounder adjustments, we assessed associations of standard categorisations of prospectively ascertained pre-pregnancy overweight and obesity (OWOB), gestational weight gain (GWG) and substantial post-delivery weight retention (PDWR) with post-delivery dysglycaemia (n = 692). Women with GDM had a higher risk of later T2D [relative risk (95% CI) 12.07 (4.55, 32.02)] and dysglycaemia [3.02 (2.19, 4.16)] compared with non-GDM women. Independent of GDM, women with pre-pregnancy OWOB also had a higher risk of post-delivery dysglycaemia. Women with GDM who were OWOB pre-pregnancy and had subsequent PDWR (≥ 5 kg) had 2.38 times (1.29, 4.41) the risk of post-delivery dysglycaemia compared with pre-pregnancy lean GDM women without PDWR. No consistent associations were observed between GWG and later dysglycaemia risk. In conclusion, women with GDM have a higher risk of T2D 4-6 years after the index pregnancy. Pre-pregnancy OWOB and PDWR exacerbate the risk of post-delivery dysglycaemia. Weight management during preconception and post-delivery represent early windows of opportunity for improving long-term health, especially in those with GDM.

Pediatric weight management, dietary restraint, dieting, and eating disorder risk: a systematic review.

CONTEXT: Whether dietary restraint and dieting are risk factors associated with eating disorders has not been explored in the context of pediatric weight management. OBJECTIVE: To review associations between dietary pediatric weight management, dietary restraint, dieting, and eating disorder risk. DATA SOURCES, SELECTION, AND EXTRACTION: Four databases - MEDLINE, EMBASE, Cochrane Library, and PsycINFO - were searched to May 2020 to identify pediatric weight management interventions with a dietary component for children and adolescents with overweight or obesity. The review was limited to studies reporting dietary restraint and/or dieting at preintervention, postintervention, and/or follow-up. Screening and quality assessment were conducted in duplicate, and data extraction was completed by 1 reviewer and cross-checked for accuracy. Data extracted included study characteristics, dietary restraint/dieting, and eating disorder-related outcomes (including disordered eating, body image, self-esteem, depression, and anxiety). RESULTS: A total of 26 papers, representing 23 studies, were included. Of these, 20 studies reported on dietary restraint, which increased (10 postintervention, 6 follow-up) or remained unchanged (7 postintervention, 5 follow-up), and 5 studies reported on dieting, which increased (1 study), remained unchanged (2 studies) or decreased (2 studies) postintervention. All studies that reported on other eating disorder risk factors (eg, binge eating, body dissatisfaction, and depression) and weight-related outcomes found improvement or no change postintervention or at follow-up. CONCLUSION: The results of this review suggest that current measures of dietary restraint and dieting are not associated with eating disorder risk within the context of pediatric weight management; however, long-term data is limited. In addition, those current measures may not be suitable risk markers. Concerns about dietary restraint and dieting leading to eating disorders should not prevent access to quality care for young people with obesity. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. 2017 CRD42017069488.

The impact of early body-weight variability on long-term weight maintenance: exploratory results from the NoHoW weight-loss maintenance intervention.

BACKGROUND: Weight-loss programmes often achieve short-term success though subsequent weight regain is common. The ability to identify predictive factors of regain early in the weight maintenance phase is crucial. OBJECTIVE: To investigate the associations between short-term weight variability and long-term weight outcomes in individuals engaged in a weight-loss maintenance intervention. METHODS: The study was a secondary analysis from The NoHoW trial, an 18-month weight maintenance intervention in individuals who recently lost ≥5% body weight. Eligible participants (n = 715, 64% women, BMI = 29.2 (SD 5.0) kg/m2, age = 45.8 (SD 11.5) years) provided body-weight data by smart scale (Fitbit Aria 2) over 18 months. Variability in body weight was calculated by linear and non-linear methods over the first 6, 9 and 12 weeks. These estimates were used to predict percentage weight change at 6, 12, and 18 months using both crude and adjusted multiple linear regression models. RESULTS: Greater non-linear weight variability over the first 6, 9 and 12 weeks was associated with increased subsequent weight in all comparisons; as was greater linear weight variability measured over 12 weeks (up to AdjR2 = 4.7%). Following adjustment, 6-week weight variability did not predict weight change in any model, though greater 9-week weight variability by non-linear methods was associated with increased body-weight change at 12 (∆AdjR2 = 1.2%) and 18 months (∆AdjR2 = 1.3%) and by linear methods at 18 months (∆AdjR2 = 1.1%). Greater non-linear weight variability measured over 12 weeks was associated with increased weight at 12 (∆AdjR2 = 1.4%) and 18 (∆AdjR2 = 2.2%) months; and 12-week linear variability was associated with increased weight at 12 (∆AdjR2 = 2.1%) and 18 (∆AdjR2 = 3.6%) months. CONCLUSION: Body-weight variability over the first 9 and 12 weeks of a weight-loss maintenance intervention weakly predicted increased weight at 12 and 18 months. These results suggest a potentially important role in continuously measuring body weight and estimating weight variability.

Relationship between Sleep and Hedonic Appetite in Shift Workers.

Short and/or poor sleep are established behavioral factors which can contribute to excess food intake, and emerging evidence suggests that disturbed circadian rhythms may also impact food intake regulation. Together, disturbed sleep and circadian rhythms may help explain the excess risk for obesity seen in shift workers. To date, however, the details of how shift work may impact food intake regulation are still not fully defined. Here we examined the relationship between sleep characteristics and hedonic control of appetite in shift workers. A total of 63 shift workers (mean (M) age: 36.7 years, standard deviation (SD): 12.0; 59% women) completed an online survey comprising self-reported measures of body weight regulation, sleep (Pittsburgh Sleep Quality Index, Sleep Hygiene Index), and hedonic control of appetite (Food Craving Inventory, Power of Food Scale). Seventy-one percent reported some weight change since starting shift work, and 84% of those reported weight gain (M = +11.3 kg, SD = 9.1). Worse sleep quality and shorter sleep duration were associated with more food cravings, and worse sleep quality and hygiene were associated with higher appetitive drive to consume palatable food (greater hedonic drive). This preliminary study suggests hedonic pathways are potentially contributing to weight gain in shift workers with disturbed sleep.