Early time-restricted eating with energy restriction has a better effect on body fat mass, diastolic blood pressure, metabolic age and fasting glucose compared to late time-restricted eating with energy restriction and/or energy restriction alone: A 3-month randomized clinical trial.
Level 2 - randomized trial
Individual randomized controlled trial with active comparator arms
PubMed 40250088 · doi:10.1016/j.clnu.2025.04.001
What was done
A 3-month trial evaluated the effects of 8-h early time-restricted eating plus energy restriction (eTRE + ER, n = 37), 8-h late time-restricted eating plus energy restriction (lTRE + ER, n = 37), and 12-h energy restriction alone (ER, n = 34) in 108 adults with overweight and obesity. Participants were allocated according to personal chronotype. Energy restriction targets were set based on individual resting metabolic rate. Anthropometric and cardiometabolic risk factors were measured at baseline, 1, 2, and 3 months; sleep quality and quality of life were assessed at baseline and 3 months. Data were analyzed using a per-protocol approach in 93 completers (34 eTRE + ER, 28 lTRE + ER, 31 ER).
What was found
Total body mass loss after 3 months did not significantly differ between groups (p = 0.319): -5.0 kg (95% CI, -5.7 to -4.3) for eTRE + ER, -4.4 kg (95% CI, -5.2 to -3.6) for lTRE + ER, and -4.3 kg (95% CI, -5.0 to -3.6) for ER alone. Between-group comparisons showed: - eTRE + ER vs. lTRE + ER: greater reduction in fat mass (-1.2%, 95% CI, -2.1 to -0.2; p = 0.013) and fasting blood glucose (-0.35 mmol/L, 95% CI, -0.63 to -0.06; p = 0.012). - eTRE + ER vs. ER alone: greater reduction in fat mass (-1.1%, 95% CI, -2.0 to -0.1; p = 0.022), metabolic age (-3 years, 95% CI, -5 to 0; p = 0.028), and diastolic blood pressure (-4 mmHg, 95% CI, -8 to 0; p = 0.033). - No significant between-group differences were detected for other measured anthropometric, biochemical, and quality-of-life parameters.
Why it matters
Aligning an 8-hour daily eating window earlier in the day may offer small cardiometabolic advantages—such as improved glucose regulation, lower diastolic blood pressure, and greater relative fat loss—over late eating windows or calorie restriction alone, even when total weight loss remains identical.
Limits
The study used a per-protocol analysis rather than intention-to-treat, dropping the 15 participants (14%) who did not complete the protocol. Allocation was based on personal chronotype rather than pure simple randomization, introducing potential confounding. The duration was relatively short (3 months) and sample size was modest.
Cited by
- supports Eating earlier in the day is associated with better overall cardiometabolic health.