Meal Timing and Anthropometric and Metabolic Outcomes: A Systematic Review and Meta-Analysis

Area of Science:

• Metabolic Health
• Nutritional Science
• Weight Management

Background:

• Meal timing strategies like time-restricted eating (TRE) are explored for weight loss and metabolic health benefits.
• Long-term efficacy of these strategies, particularly in chronic disease management, remains largely unknown.

Purpose of the Study:

• To evaluate the association between meal timing strategies and anthropometric and metabolic indicators.
• Assess interventions lasting at least 12 weeks.

Main Methods:

• Systematic search of Medline, Embase, CINAHL, and Cochrane CENTRAL up to October 2023.
• Inclusion of randomized clinical trials (RCTs) in adults evaluating within-day meal timing patterns for ≥12 weeks.
• Meta-analysis using random-effects models, with study quality assessed by Risk of Bias 2.0.

Main Results:

• Twenty-nine RCTs with 2485 participants were included.
• Time-restricted eating (TRE) showed a statistically significant weight reduction (-1.37 kg).
• Lower meal frequency and earlier caloric distribution also correlated with greater weight change (-1.85 kg and -1.75 kg, respectively).

Conclusions:

• TRE, reduced meal frequency, and earlier caloric distribution may modestly reduce weight compared to standard care.
• Effect sizes were small, and clinical significance is uncertain due to high heterogeneity and risk of bias.
• Further high-quality research with larger sample sizes and longer follow-up is recommended.