The effect of zinc supplementation on brain derived neurotrophic factor: A meta-analysis

source extracted confidence: high 2026-04-09
#brain #brain-derived-neurotrophic-factor #dietary-supplements #humans #zinc

The effect of zinc supplementation on brain derived neurotrophic factor: A meta-analysis

Jafari et al., 2021 | J Trace Elem Med Biol | Meta Analysis

Citation

Jafari Fatemeh, Mohammadi Hamed, Amani Reza. The effect of zinc supplementation on brain derived neurotrophic factor: A meta-analysis. J Trace Elem Med Biol. 2021-Jul;66:126753. doi:10.1016/j.jtemb.2021.126753

Abstract

BACKGROUND: Zinc in one of the most abundant trace minerals in human body which is involved in numerous biological pathways and has variety of roles in the nervous system. It has been assumed that zinc exerts its role in nervous system through increasing brain derived neurotrophic factor (BDNF) concentrations. OBJECTIVES: Present meta-analysis was aimed to review the effect of zinc supplementation on serum concentrations of BDNF. METHODS AND MATERIALS: Four electronic databases (Pubmed, Scopus, Web of Science, Embase) were searched for identifying studies that examined BDNF levels prior and after zinc supplementation up to May 2020. According to the Cochrane guideline, a meta-analysis was performed to pool the effect size estimate (Hedges' test) of serum BDNF across studies. Risk of publication bias was assessed using a funnel plot and Egger's test. RESULTS: Five studies were eligible and 238 participants were included. These studies enrolled subjects with premenstrual syndrome, diabetic retinopathy, major depression disorder, overweight/obese and obese with mild to moderate depressive disorders. Zinc supplementation failed to increase blood BDNF concentrations with effect size of 0.30 (95 % CI: -0.08, 0.67, P = 0.119). Funnel plot did not suggest publication bias. CONCLUSION: Zinc supplementation may not significantly increase BDNF levels. However, the small number of included articles and significant heterogeneity between them can increase the risk of a false negative result; therefore, the results should be interpreted with caution.

Key Findings

Five studies were eligible and 238 participants were included. These studies enrolled subjects with premenstrual syndrome, diabetic retinopathy, major depression disorder, overweight/obese and obese with mild to moderate depressive disorders. Zinc supplementation failed to increase blood BDNF concentrations with effect size of 0.30 (95 % CI: -0.08, 0.67, P = 0.119). Funnel plot did not suggest publication bias.

Outcomes Measured

  • depression

Population

Field Value
Population premenstrual syndrome
Sample Size 238
Age Range See abstract
Condition depression

MeSH Terms

  • Brain
  • Brain-Derived Neurotrophic Factor
  • Dietary Supplements
  • Humans
  • Zinc

Evidence Classification

  • Level: Meta Analysis
  • Publication Types: Journal Article, Meta-Analysis, Review
  • Vertical: zinc

Provenance

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