The Effect of Time-Restricted Eating on Sleep: A Systematic Review and Meta-analysis

CONTEXT: The bidirectional relationship between sleep and the circadian clock has prompted many studies investigating the effects of time-restricted eating (TRE) on sleep, although with inconsistent results. OBJECTIVE: This systematic review and meta-analysis aimed to comprehensively evaluate the effects of TRE on sleep. DATA SOURCES: The PubMed, Embase, and Cochrane Library databases were searched for relevant studies investigating the effects of TRE on sleep, published up to February 5, 2024. DATA EXTRACTION: Changes in sleep duration, Pittsburgh Sleep Quality Index (PSQI), wake-up time, and sleep-onset time from baseline were extracted and analyzed using R language (2021; R Core Team, Vienna, Austria). DATA ANALYSIS: The quality of the studies was assessed using a methodological index for a nonrandomized studies checklist and the Cochrane Risk of Bias 2 tool. Thirteen studies comprising 638 participants who fulfilled the inclusion criteria were included. Meta-analysis based on single-arm studies and TRE arms revealed that the TRE intervention significantly increased sleep duration (mean change [MC]: 0.13; 95% CI: 0.01-0.25; P = .03) and decreased the PSQI (pooled MC: -0.47; 95% CI: -0.80 to -0.15; P < .01, I2 = 0%, P = .43). Participants with early TRE exhibited low PSQI scores after the intervention (pooled mean difference: -0.77; 95% CI: -1.29 to -0.24; P < .01). However, meta-analysis based on controlled trials revealed no differences in sleep duration or PSQI scores. Pooled results revealed that TRE had no significant effect on sleep-onset or wake-up time. CONCLUSION: Current evidence suggests that TRE may have a modest effect on sleep; however, further studies are required to verify this hypothesis.