Higher fruit and vegetable intake was associated with modest reductions in depressive symptoms over 5 to 11 years, according to a recent study. Findings for fruit intake were less conclusive.

Researchers conducted a longitudinal study to evaluate associations between fruit and vegetable intake and depressive symptoms in middle-aged and older adults. The study included 3,483 twins aged 45 to 90 years from cohorts in Australia, Denmark, Sweden, and the U.S., as part of the Interplay of Genes and Environment across Multiple Studies (IGEMS) consortium. Dietary intake was categorized as low, moderate, or high using food frequency questionnaires. Depressive symptoms were assessed using validated tools, and harmonized scores were analyzed on continuous scales over 5 to 11 years. The researchers employed linear mixed-effects models and ICE FALCON methodology to examine familial confounding.

At baseline, participants reported daily fruit and vegetable intakes of 1.0 servings (SD 0.8) and 1.2 servings (SD 0.8), respectively. High vegetable intake was associated with a reduction in depressive symptoms compared with low intake (β = −0.006; 95% CI −0.011 to −0.002; p = 0.002). Moderate vegetable intake also showed a protective effect (β = −0.005; 95% CI −0.009 to −0.001; p = 0.014). High fruit intake was linked to lower depressive symptoms (β = −0.007; 95% CI −0.014 to <−0.001; p = 0.040), but findings were less robust. Including potatoes in sensitivity analyses nullified vegetable-related associations, potentially due to preparation methods.

Co-twin analysis indicated no familial confounding for the vegetable-depression relationship. However, findings for fruit intake remained inconclusive. The study noted dietary intakes in high categories were below World Health Organization recommendations and that all cohorts were from high-income countries.

The findings, published in Scientific Reports, underscore the need for standardized dietary assessments and clinical evaluations of depression in future studies.