Nutritional interventions and sleep quality in obese individuals: a systematic review and meta-analysis of randomized...

Poor sleep is closely associated with obesity and contributes to hormonal dysregulation and weight gain. This meta-analysis aimed to evaluate the effects of nutritional interventions on the sleep quality of individuals with obesity, focusing on strategies, such as calorie restriction, high-protein diets, and plant-based supplementation.

A systematic literature search was conducted on PubMed, Embase, Web of Science, and the Cochrane Library, covering publications from inception up to January 2025. Randomized controlled trials (RCTs) assessing nutritional interventions and sleep quality were also included. The risk of bias (ROB) was assessed using Cochrane's ROB 2 tool, and a meta-analysis was performed using the Comprehensive Meta-Analysis software. The results were reported as odds ratios (ORs) with 95% confidence intervals (CIs), and heterogeneity was evaluated using the I² statistic.

Eleven RCTs involving 637 participants demonstrated that compared with the controls, the nutritional intervention significantly improved sleep quality (OR = 2.52, 95% CI [1.57, 4.03], P = 0.000). Specific interventions, such as saffron supplementation (OR = 11.10, P = 0.000), showed varying degrees of effectiveness. Long-term interventions (≥ 16 weeks) yielded consistent benefits, whereas moderate heterogeneity was observed (I² = 67.43%, P = 0.027).

Nutritional interventions, especially those that include calorie restriction, high-protein diets, and plant-based supplementation, have the potential to improve sleep quality in adults with obesity. Long-term interventions (≥ 16 weeks) may offer the most effective benefits.