Updated systematic review and meta-analysis of the effects of n-3 long-chain polyunsaturated fatty acids on depressed mood
Abstract
BACKGROUND: The debate over a role for n-3 long-chain polyunsaturated fatty acids (n-3 PUFAs) in depressed mood continues.
OBJECTIVE: The objective was to update a previous systematic review and meta-analysis of published randomized controlled trials investigating the effects of n-3 PUFAs on depressed mood and to explore potential sources of heterogeneity.
DESIGN: Eight databases were searched for trials that randomly assigned participants to receive n-3 PUFAs/fish, measured depressed mood, used human participants, and included a comparison group up to April 2009.
RESULTS: Thirty-five randomized controlled trials were identified; 17 were not included in the previous review. The pooled standardized difference in mean outcome of the 29 trials that provided data to allow pooling (fixed-effects model) was 0.10 SD (95% CI: 0.02, 0.17) in those who received n-3 PUFAs compared with placebo, with strong evidence of heterogeneity (I(2) = 65%, P < 0.01). The presence of funnel plot asymmetry suggested that publication bias was a likely source of this heterogeneity. Depressive symptom severity and participant diagnosis also explained some of the observed heterogeneity. Greater effects of n-3 PUFAs were found in individuals with more-severe depressive symptoms. In trials that enrolled individuals with a diagnosed depressive disorder, the combined mean difference was 0.41 (95% CI: 0.26, 0.55), although evidence of heterogeneity was also found (I(2) = 71%). In trials that enrolled…
How strong is the evidence?
Evidence Hub reads this as a meta-analysis, done in people. Its evidence level is 1 of 5 (Highest · pooled evidence). Pooled evidence from several studies sits at the top of the evidence pyramid.
Read the paper
Related studies
- Promising Sources of Plant-Derived Polyunsaturated Fatty Acids: A Narrative Review
- Effects of omega-3 polyunsaturated fatty acid intake in patients with chronic kidney disease: Systematic review and meta-analysis of randomized controlled trials
- Effect of omega-3 fatty acids on cognition: an updated systematic review of randomized clinical trials
- The role of omega-3 polyunsaturated fatty acid supplementation in the management of type 2 diabetes mellitus: A narrative review
- Paucity of evidence for a relationship between long-chain omega-3 fatty acid intake and chronic obstructive pulmonary disease: a systematic review
- Omega-3 fatty acid nanocarriers: Characterization and potential applications
Go deeper in Evidence Hub
Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.