Study of Time-restricted Eating on Weight Loss. (TREAT)

Study of Time-restricted Eating on Weight Loss. A Randomized Controlled Trial of the Effects of Time-restricted Eating on Weight Loss in Obese Subjects.

This is a randomized controlled trial studying the effects of time-restricted eating (TRE) on weight loss in obese humans. Obesity is the number one risk factor for type 2 Diabetes Mellitus (T2DM), and numerous studies demonstrate that weight loss is an effective strategy to prevent T2DM and improve the metabolic health of people diagnosed with T2DM. Unfortunately, classical calorie restriction diets often fail to produce long-term weight loss due to low compliance, reduced resting metabolic rate (RMR), and other factors. Therefore, novel dieting techniques must be explored in order to successfully treat obesity and prevent T2DM. Studies in mice provide compelling evidence that feeding/fasting cycles can be altered to produce beneficial effects on weight loss and metabolic health markers in the absence of calorie restriction. Limited research in human subjects suggests that this feeding paradigm may translate to human health as well, however, more research needs to be done in order to confirm this hypothesis. This study will determine if TRE can lead to weight loss in obese human subjects. Secondary outcomes include changes in body composition, HOMA-IR, hormonal and biochemical serum markers, RMR, and total energy expenditure (TEE).

This is a randomized controlled trial. Participants will randomly assigned to one of two diet interventions for the duration of the 12-week study.

Participants in this group will be instructed to fast every day from 8pm until 12pm the following day. From 12pm until 8pm, participants can eat and drink whatever they want. During fasting hours, participants can drink water and black coffee.

Participants in this group will be instructed to eat three daily meals during specified eating times. Their first meal will be between 7am-11am. Second meal between 11am and 3pm, and third meal between 4pm-10pm. Participants will be encouraged to eat small snacks if needed so that they can eat their next meal during the specified window.

Research team will prescribe an eating plan for the participant to follow for the 12 week study. The eating plan will consist of eating during a specified 8 hour window and fasting for the remaining 16 hours of the day.

Research team will prescribe an eating plan for the participant to follow for the 12 week study.The eating plan will consist of eating three structured meals each day during three specified meal windows.

Will measure participants total energy expenditure during the week leading up to the study start and during the final week of the study

Inclusion Criteria: BMI between 30-40 kg/m2 Participants must regularly consume breakfast (at least 5 days per week) Must speak, read, and comprehend English Access to reliable internet and/or wifi Must have a valid email address and phone number Must have a cellular phone with data plan Exclusion Criteria: HIV or immunocompromised Current or past cancer diagnosis Pregnant, breastfeeding, or planned pregnancy in next 6 months Beginning or ending hormonal contraception in next 6 months Current diagnosis of type or type 2 diabetes Currently taking glucose-lowering drugs, statins, or oral steroids History of gastric bypass surgery or any other weight-loss surgery History of anorexia or bulimia Frequent travel across time zones or unusual work hours Unable to fast for prolonged periods due to medical condition Unable to stand for several minutes without aid Cannot lie down on cushioned table for 30 minutes No internal metal artifacts that would alter body composition Unable to travel to UCSF for in-person testing Requires translator services

Lowe DA, Wu N, Rohdin-Bibby L, Moore AH, Kelly N, Liu YE, Philip E, Vittinghoff E, Heymsfield SB, Olgin JE, Shepherd JA, Weiss EJ. Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters in Women and Men With Overweight and Obesity: The TREAT Randomized Clinical Trial. JAMA Intern Med. 2020 Nov 1;180(11):1491-1499. doi: 10.1001/jamainternmed.2020.4153. Erratum In: JAMA Intern Med. 2020 Nov 1;180(11):1555. JAMA Intern Med. 2021 Jun 1;181(6):883.