Feasibility of Three Different 8h Time-Restricted Eating Schedules Over 4 Weeks in Spanish Adults With Overweight/Obesity: A Pilot Randomized Controlled Trial

Abstract

Abstract Objectives To investigate the feasibility and acceptability of three different 8h time-restricted eating (TRE) schedules (i.e., early TRE, late TRE, and self-selected TRE) over 4 weeks in adults with overweight/obesity from southern Spain. Methods A total of 22 adults with overweight/obesity and a baseline eating window ≥12h (13 women; 48 ± 10 years old; body mass index: 32.7 ± 5.8 kg/m2) were randomly assigned to one of the three 8h-TRE schedules: early TRE (first meal within the first 2h after waking up), late TRE (first meal 5–7h after waking up), and self-selected TRE (self-selected eating window). Feasibility and acceptability were assessed by adherence to the intervention, adverse events and validated questionnaires to assess sleep quality, depression, and anxiety. Results All participants completed the intervention. Adherence remained ≥95% in the late and self-selected TRE groups during the intervention, whereas it decreased from 94% (first week) to 68% (fourth week) in the early TRE group. Total adherence was not associated with baseline eating window (P = 0.644). The mean intervention eating window was 7.9 ± 0.5h, 7.1 ± 0.5h, and 7.4 ± 0.5h for the early, late, and self-selected TRE, respectively. Differences were noted between early and late TRE groups (P = 0.019). No serious adverse events were reported and no differences were observed in headache, nausea, acidity, diarrhea, thirstiness, hunger, cravings, tiredness, stress, irritability, and anxiety eating among TRE groups. After the intervention, the early TRE improved depression using two different validated questionnaires (P = 0.007 and P = 0.018), although no differences were observed across TRE groups (P = 0.863 and P = 0.197). A trend to significant improvement in sleep quality (P = 0.067) was observed in the early TRE group after the intervention, albeit no differences were noticed across TRE groups (P = 0.277). Conclusions These results suggest that early TRE may have lower feasibility and acceptability than late and self-selected TRE in adults with overweight/obesity from southern Spain. However, early TRE appears to enhance depression and sleep quality. Lastly, no serious adverse events were noted; hence, TRE seems a safe nutrition. Funding Sources N/A.