IMPORTANCEIt is unclear how effective intermittent fasting is for losing weight and body fat, and the effects may depend on the timing of the eating window. This randomized trial compared time-restricted eating (TRE) with eating over a period of 12 or more hours while matching weight-loss counseling across groups.OBJECTIVE To determine whether practicing TRE by eating early in the day (eTRE) is more effective for weight loss, fat loss, and cardiometabolic health than eating over a period of 12 or more hours. DESIGN, SETTING, AND PARTICIPANTSThe study was a 14-week, parallel-arm, randomized clinical trial conducted between August 2018 and April 2020. Participants were adults aged 25 to 75 years with obesity and who received weight-loss treatment through the Weight Loss Medicine Clinic at the University of Alabama at Birmingham Hospital.INTERVENTIONS All participants received weight-loss treatment (energy restriction [ER]) and were randomized to eTRE plus ER (8-hour eating window from 7:00 to 15:00) or control eating (CON) plus ER (Ն12-hour window). MAIN OUTCOMES AND MEASURESThe co-primary outcomes were weight loss and fat loss. Secondary outcomes included blood pressure, heart rate, glucose levels, insulin levels, and plasma lipid levels.RESULTS Ninety participants were enrolled (mean [SD] body mass index, 39.6 [6.7]; age, 43 [11] years; 72 [80%] female). The eTRE+ER group adhered 6.0 (0.8) days per week. The eTRE+ER intervention was more effective for losing weight (−2.3 kg; 95% CI, −3.7 to −0.9 kg; P = .002) but did not affect body fat (−1.4 kg; 95% CI, −2.9 to 0.2 kg; P = .09) or the ratio of fat loss to weight loss (−4.2%; 95% CI, −14.9 to 6.5%; P = .43). The effects of eTRE+ER were equivalent to reducing calorie intake by an additional 214 kcal/d. The eTRE+ER intervention also improved diastolic blood pressure (−4 mm Hg; 95% CI, −8 to 0 mm Hg; P = .04) and mood disturbances, including fatigue-inertia, vigor-activity, and depression-dejection. All other cardiometabolic risk factors, food intake, physical activity, and sleep outcomes were similar between groups. In a secondary analysis of 59 completers, eTRE+ER was also more effective for losing body fat and trunk fat than CON+ER. CONCLUSIONS AND RELEVANCEIn this randomized clinical trial, eTRE was more effective for losing weight and improving diastolic blood pressure and mood than eating over a window of 12 or more hours at 14 weeks.TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT03459703

SummaryObjectiveThe increase in technology and online social networks (OSNs) may present healthcare providers with an innovative modality for delivering weight management programmes that could have an impact on health care at the population level. The objective of this study was to evaluate the feasibility and efficacy of using an OSN to deliver a weight loss programme to inform future, large‐scale trials.MethodsSeventy individuals (age = 47 ± 12.4, minority = 24.3%) with obesity (BMI = 36.2 ± 4.0) completed a 6‐month weight loss intervention and were randomized to either a conference call or OSN delivery group. Weight loss was achieved by reducing energy intake by 500–700 kcal·d−1 below estimated total daily energy expenditure and progressing physical activity to 300 min/week. Behavioural weight loss strategies were delivered weekly throughout the intervention.ResultsConference call and OSN groups produced clinically meaningful weight loss of ≥5% from baseline to 6 months (phone = −6.3 ± 6.4%, OSN = −5.8 ± 6.7%). There was no significant difference in weight change between groups (p = 0.765).ConclusionThe phone and OSN groups met the American Heart Association/American College of Cardiology/The Obesity Society's Guidelines by reducing baseline weight by 5–10% within 6 months. OSNs appear to be a viable delivery platform for weight loss interventions; however, larger scale adequately powered trials are needed.

Introduction Currently, no systematic review/meta-analysis has examined studies that used online social networks (OSN) as a primary intervention platform. Therefore the purpose if this review was to evaluate the effectiveness of weight management interventions delivered through OSN. Methods PubMed, Embase, PsycINFO, Web of Science, and Scopus were searched (January 1990-November 2015) for studies with data on the effect OSNs on weight loss. Only primary source articles that utilized OSN as the main platform for delivery of weight management/healthy lifestyle interventions, were published in English language peer-reviewed journals, and reported outcome data on weight were eligible for inclusion in this systematic review. Five articles were included in this review. Results One-hundred percent of the studies (n=5) reported a reduction in baseline weight. Three of the five studies (60%) reported significant decreases in body weight when OSN was paired with health educator support. Only one study reported a clinical significant weight loss of ≥5%. Conclusion Using OSN for weight management is in its early stages of development and while these few studies show promise, more research is needed to acquire information about optimizing these interventions to increase their efficacy.

Summary Poor adherence is a barrier to successful weight control. Intermittent energy restriction (IER) provides an alternative approach to those for whom daily energy restriction is not ideal. This study assessed changes in weight, body composition, and macronutrient intake for an IER and a continuous energy restriction (CONT) approach within a multicomponent weight management intervention. We randomized 35 adults with overweight/obesity (BMI = 31.2 ± 2.4 kg/m2) to CONT or IER for 24 weeks (12‐week weight loss intervention and 12 weeks of weight loss maintenance). Diets were delivered within a multimodal weight management program including weekly group meetings with a registered dietitian, increased physical activity, and a comprehensive lifestyle change program. Retention and adherence were similar for CONT and IER. Weight, BMI, fat mass, percentage body fat, waist circumference, hip circumference, blood pressure, and heart rate all decreased after 24 weeks (all, P < .01), but there were no main effects of group (all, P > .27). Weight loss was clinically relevant in both CONT (11.38 ± 7.9%) and IER (9.37 ± 9.7%), and the proportion of each group achieving 5% weight loss was 82 and 61% (P = .16), respectively. Participant satisfaction was high in both groups. The results from this study (a) support the feasibility of IER as an alternative for weight loss and weight loss maintenance, (b) indicate that IER is an effective alternative to CONT for weight control and improvements in body composition, and (c) emphasize the importance of intensive lifestyle interventions with ongoing support for effective behaviour modification.