Time-Restricted Eating Without Calorie Counting for Weight Loss in a Racially Diverse Population : A Randomized Controlled Trial.
Level 2 - randomized trial
Individual randomized controlled trial
PubMed 37364268 · doi:10.7326/M23-0052
What was done
In a 12-month randomized controlled trial at the University of Illinois Chicago, 90 adults with obesity (mean age 40 years; 33% Black, 46% Hispanic) were randomized to 8-hour time-restricted eating without calorie counting (eating window noon to 8:00 p.m.), calorie restriction (25% daily energy restriction), or a control group eating over 10 or more hours per day. Participants were not blinded. The study assessed changes in body weight, metabolic markers, and energy intake at 12 months.
What was found
Seventy-seven participants completed the study. Mean energy intake reduction was -425 kcal/d (SD, 531) for time-restricted eating and -405 kcal/d (SD, 712) for calorie restriction. Compared with control, 12-month weight loss was -4.61 kg (95% CI, -7.37 to -1.85 kg; P ≤ 0.01; -4.87%) in the time-restricted eating group and -5.42 kg (95% CI, -9.13 to -1.71 kg; P ≤ 0.01; -5.30%) in the calorie restriction group. The difference between time-restricted eating and calorie restriction was not statistically significant (0.81 kg [95% CI, -3.07 to 4.69 kg; P = 0.68]; 0.43% [95% CI, -3.48% to 4.34%]). Specific numeric outcomes for metabolic markers were not provided in the abstract.
Why it matters
This 12-month trial demonstrates that an 8-hour time-restricted eating window without calorie counting achieves weight loss comparable to standard daily calorie restriction in a racially diverse cohort.
Limits
The trial was not blinded, was not powered to detect relatively large differences between active interventions, lacked adjustment for multiple comparisons, had a modest sample size (90 enrolled, 77 completers), and did not report quantitative metabolic marker results in the abstract.
Cited by
- supports In free-living conditions, people practicing time-restricted eating spontaneously decrease their caloric intake by 200 to 500 calories depending on the feeding window length.