Research

Mixed

Whole-of-dietary interventions significantly reduce symptoms of depression compared to control conditions, with a small-to-moderate effect size (Hedges' g = 0.275).

Improving your overall diet quality, whether by focusing on nutrients, reducing fat, or managing weight, can help reduce depressive symptoms. This is supported by a large body of research involving tens of thousands of people. You don't need a perfect diet, but making whole-of-diet changes is more effective than focusing on single nutrients.

GoodSupportsHIGH confidence
dietary interventions significantly reduced depressive symptoms (g = 0.275, 95% CI = 0.10 to 0.45, p = .002).
Joseph Firth et al. · Psychosomatic Medicine · 2019

Why this rating

Meta-analysis of 16 RCTs with over 45,000 participants provides high-level evidence, though heterogeneity exists.

Source

The Effects of Dietary Improvement on Symptoms of Depression and Anxiety: A Meta-Analysis of Randomized Controlled Trials

Joseph Firth et al. · Psychosomatic Medicine · 2019

DOI 10.1097/psy.0000000000000673

Meta-analysis · 16 studiesCited 542×
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DOI resolved against Crossref · corpus check 2026-06-10

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