Sleep problems are prevalent during adolescence, and modifying dietary factors may contribute to better sleep outcomes in adolescents. This systematic review and meta-analysis aimed to evaluate the impact of modifiable dietary factors on sleep health among adolescents.A systematic search of records from six databases including MEDLINE, PubMed, Embase, Scopus, CINAHL, and the CENTRAL from inception up to November 2023, identified 33 peer-reviewed publications that assessed the relationship between modifiable dietary factors and sleep outcomes in adolescents aged 12-18 years. The NIH Quality Assessment Tools were used to assess the quality of the included studies. Meta-analysis was performed on a sub-group of studies (n = 6) to ascertain the effect of dietary factors on sleep health.Although the included studies were predominantly cross-sectional and exhibited heterogeneity, relying mainly on self-reported measures, it was observed that consumption of healthy foods was consistently linked with improved sleep outcomes among adolescents, whereas higher intake of fat-rich or sugar-rich foods and red meats or processed food was associated with poorer sleep features. The meta-analysis further substantiated that adolescents with higher caffeine intake faced increased odds of sleep problems (OR = 1.67, 95% CI: 1.28-2.17), while alcohol consumption was significantly associated with insomnia (OR = 1.17, 95% CI: 1.07-1.27).Overall, despite high heterogeneity among studies, this systematic review underscores the promising role of healthy dietary factors in enhancing both the quality and quantity of sleep in adolescents. The meta-analysis results also highlight that reducing caffeine and alcohol intake holds potential for supporting better sleep in this population. However, further validation through intervention studies is warranted.Copyright © 2024 Elsevier B.V. All rights reserved.