Effects of time-restricted feeding on body weight, body composition, and cardiometabolic health: a systematic review and meta-analysis.

Abstract

Obesity is a major global public health challenge. Animal studies suggests promising effects of time-restricted feeding (TRF) regimens for obesity management, however, human studies with TRF have yet to be synthesised. Therefore, this systematic review and meta-analysis aimed to investigate the effects of TRF on body weight (BW), body composition and cardiometabolic health parameters in humans. Studies were searched from MEDLINE, Web of Science and Cochrane Library. Nineteen studies (11 randomised controlled trials [RCTs], 3 non-RCTs and 5 uncontrolled before-and-after studies) were included in the systematic review (n= 583 participants), and twelve (9 RCTs and 3 non-RCTs) in a random-effects meta-analysis (n= 443 participants). Compared to control groups, TRF significantly reduced BW (mean difference (MD), -1.17kg, 95% confidence interval (CI): -1.62, -0.71; p < 0.00001) and fat mass (MD: -1.57kg, 95%CI: -1.69, -1.45; p < 0.00001), while preserving fat-free mass (MD: 0.39kg, 95%CI -0.48, 1.27; p = 0.38). TRF also reduced fasting insulin levels, with larger reductions in overweight/obese individuals (MD: -2.95µU/mL, 95%CI: -4.95, -0.95; p = 0.004) than in lean individuals (MD: -0.67µU/mL, 95%CI: -1.01, -0.32; p = 0.0002). No between-group differences in fasting glucose were found. TRF is effective at reducing BW, fat mass and insulin levels, especially in overweight/obese individuals. However, further large-scale trials are warranted to confirm these results.