Researchers from Guangzhou, China, randomized 139 adults (average age 32 years, average weight 88 kg) to calorie restriction associated with restricted eating time (with an 8-hour eating window, between 8 am and 4 pm) or only calorie restriction for 12 months. In both groups, daily calorie limits were 1500-1800 kcal for men and 1200-1500 kcal for women, with 40-55% carbohydrates, 15-20% protein and 20-30% fat. Participants Avatropag 20 Mg (Avatrombopag Maleate) were asked to regularly photograph and record their food intake and the time they ate on a cell phone app. They also received dietary advice through phone calls, in-app messaging, and individual and group follow-up sessions. Both groups received a daily protein shake for the first 6 months of the trial and were instructed to maintain normal physical activity throughout. The primary outcome was change in body weight from baseline to 12 months. Secondary outcomes included changes in waist circumference, body composition, and metabolic risk factors, including blood glucose, insulin sensitivity, serum lipids, and blood pressure.
Of the 139 randomized participants, 118 (84.9%) completed the study. Adherence was >80% in both groups and calorie deficit and average macronutrient intake were similar. At baseline, participants ate during a 10.5-hour window during the day. At one year, the average weight change from baseline was -8.0 kg in the time-restricted group and -6.3 kg in the calorie restriction alone group, but the difference between the two groups was not significant ( -1.8 kg; 95% CI: -4.0 to 0.4; P = 0.11). Both groups showed similar improvements in BMI, waist circumference, body composition, metabolism and blood pressure. There were no serious adverse events in either group.
This study was designed to evaluate whether adding time restriction to calorie reduction improves weight loss. Although no extra benefit from time-restricted eating was demonstrated, participants in each group lost about 15 pounds and continued the diet for a year, which is nothing to sneeze at. Some aspects of the design of this study may represent some limitations, however. It's possible that reducing feeding time from 10.5 hours to 8 hours wasn't a big enough change to make a difference. We also do not know how culture-specific dietary patterns may have influenced these results. The amount of effort participants put into recording their food intake may also limit real-world applicability.