This is a 52-week randomized, parallel-arm clinical trial designed to assess the effects of early time restricted eating (E-TRE) vs late TRE (L-TRE) vs daily caloric restriction (DCR) within the context of a guidelines-based behavioral weight loss program. 162 adults (age 18-65) with obesity (BMI 27-45 kg/m2) will be recruited from the community and randomized 1:1:1 to E-TRE (eating within an 8-hour window starting 1-2 hours after waking), L-TRE (eating within an 8-hour window starting 5-6 hours after waking) or DCR (caloric restriction of 25% from baseline energy requirements). The primary outcome is change in body weight at 26 weeks. Secondary outcomes include body composition, insulin sensitivity, blood pressure, glucose variability, physical activity, and sleep.
The goal of this clinical trial is to learn about time restricted eating as a weight loss intervention in adults with obesity. The main questions it aims to answer are:~How does the timing of the eating window (early vs late time restricted eating) affect weight loss and changes in metabolic risk factors?~How does time restricted eating compare to standard of care (daily caloric restriction) for weight loss and changes in metabolic risk factors?~Participants will be randomly assigned to either early time restricted eating, late time restricted eating, or daily caloric restriction.~They will be asked to follow the assigned dietary strategy for 1 year and will receive a group-based program for instruction and support.~They will be asked at several times during the year to have their weight and body composition measured, provide blood samples, track their food, and wear monitors for physical activity and sleep.