The effect of vitamin D supplementation on depressive symptoms in adults: A systematic review and meta-analysis of randomized controlled trials

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#adult #humans #depression #dietary-supplements #randomized-controlled-trials-as-topic

The effect of vitamin D supplementation on depressive symptoms in adults: A systematic review and meta-analysis of randomized controlled trials

Mikola et al., 2023 | Crit Rev Food Sci Nutr | Meta Analysis

Citation

Mikola Tuomas, Marx Wolfgang, ... Ruusunen Anu. The effect of vitamin D supplementation on depressive symptoms in adults: A systematic review and meta-analysis of randomized controlled trials. Crit Rev Food Sci Nutr. 2023-Nov;63(33):11784-11801. doi:10.1080/10408398.2022.2096560

Abstract

Neurosteroid and immunological actions of vitamin D may regulate depression-linked physiology. Meta-analyses investigating the effect of vitamin D on depression have been inconsistent. This meta-analysis investigated the efficacy of vitamin D in reducing depressive symptoms among adults in randomized placebo-controlled trials (RCT). General and clinical populations, and studies of ill individuals with systemic diseases were included. Light therapy, co-supplementation (except calcium) and bipolar disorder were exclusionary. Databases Medline, PsycINFO, CINAHL and The Cochrane Library were searched to identify relevant articles in English published before April 2022. Cochrane risk-of-bias tool (RoB 2) and GRADE were used to appraise studies. Forty-one RCTs (n = 53,235) were included. Analyses based on random-effects models were performed with the Comprehensive Meta-analysis Software. Results for main outcome (n = 53,235) revealed a positive effect of vitamin D on depressive symptoms (Hedges' g = -0.317, 95% CI [-0.405, -0.230], p < 0.001, I2 = 88.16%; GRADE: very low certainty). RoB assessment was concerning in most studies. Notwithstanding high heterogeneity, vitamin D supplementation ≥ 2,000 IU/day appears to reduce depressive symptoms. Future research should investigate possible benefits of augmenting standard treatments with vitamin D in clinical depression. PROSPERO registration number: CRD42020149760. Funding: Finnish Medical Foundation, grant 4120 and Juho Vainio Foundation, grant 202100353.

Key Findings

Funding: Finnish Medical Foundation, grant 4120 and Juho Vainio Foundation, grant 202100353.

Outcomes Measured

  • depression

Population

Field Value
Population systemic diseases were included
Sample Size 53235
Age Range See abstract
Condition depression

MeSH Terms

  • Adult
  • Humans
  • Depression
  • Dietary Supplements
  • Randomized Controlled Trials as Topic
  • Vitamin D
  • Vitamins

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Meta-Analysis, Systematic Review, Journal Article
  • Vertical: vitamin-d

Provenance

Source extracted via PubMed E-utilities API on 2026-04-09