(P07-043-25) Healthy Diets Are Associated With Lower Depression, Anxiety, and Stress in Low- and Middle-Income Countries: A Meta-Analysis From a Systematic Evidence and Gap Map

Objectives: To examine the association between healthy diets and mental health (MH) in low- and middle-income countries (LMIC), because less is known about the interplay between diet and MH in LMIC compared to high income countries.

Methods: We used a systematic Evidence and Gap Map (EGM) of peer-reviewed, English language studies (published 2000-2024; n»3055) to select studies for meta-analysis. We pooled effects from studies linking ‘healthy’ dietary patterns to depression, anxiety, and stress. Measures of ‘Healthy’ diets included adherence and adequacy, dietary patterns, diet diversity and diet quality indices. Random effects models with a Fisher r-to-z transformed correlation coefficient (Coeff.) were fitted for each MH group (depression, anxiety, and stress). We examined heterogeneity among studies, influential outliers and risk of bias.

Results: Eighty-four studies from the EGM examined healthy diets and depression (n=71), anxiety (n=44), stress (n=27). Most studies were cross-sectional (n=71), used factor analysis to ascertain dietary patterns (n=27), followed by diet indices (e.g., MedDiet; n=23), dietary quality (n=19), dietary diversity (n=15), and adherence measures (n=2). Most studies were from upper middle-income countries (n=69), and Asia (n=70). We found that healthy diets were consistently associated with less depression (Coeff. -0.14 (95% CI: -0.16 to -0.11), despite high heterogeneity (Coeff. ranging from -0.70 to 0.10). Healthy diets were associated with lower anxiety (Coeff -0.12, 95% CI: -0.15 to -0.09), and lower stress (Coeff -0.12, 95% CI: -0.15 to -0.08; Coeff. range of studies: -0.43 to 0.08). Even though results were heterogeneous, they were not considered influential to the overall results. There was no observed publication bias or small study bias.

Conclusions: These first-ever pooled estimates highlight evidence gaps in low-income countries outside of Asia.  They can inform intervention gaps such as multiple marginalizations that heighten health risks, and furthermore encourage multisectoral policies and programs that improve both diet quality and mental health.

Funding Sources: Innovative Methods and Metrics for Agriculture and Nutrition Actions program funded by FCDO and BMGF