Zinc supplementation and immune factors in adults: a systematic review and meta-analysis of randomized clinical trials

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#adult #biomarkers #c-reactive-protein #dietary-supplements #humans

Zinc supplementation and immune factors in adults: a systematic review and meta-analysis of randomized clinical trials

Jafari et al., 2022 | Crit Rev Food Sci Nutr | Meta Analysis

Citation

Jafari Alireza, Noormohammadi Zeinab, ... Daneshzad Elnaz. Zinc supplementation and immune factors in adults: a systematic review and meta-analysis of randomized clinical trials. Crit Rev Food Sci Nutr. 2022;62(11):3023-3041. doi:10.1080/10408398.2020.1862048

Abstract

PURPOSE: This systematic review and meta-analysis aimed to investigate the effect of zinc supplementation on immune factors in randomized controlled trials. METHODS: A comprehensive search was done in PubMed, Scopus, Web of Science, Embase, and Cochrane databases up to December 2020. We used standard and weighted mean differences and 95% confidence intervals for net changes in selected parameters of immune responses. Subgroup analysis was used to find heterogeneity. RESULT: Overall, 35 RCTs comprising 1995 participants were eligible for this meta-analysis. There was a significant reduction of circulating CRP (WMD: -32.4; 95% CI: -44.45 to -19.62, p < 0.001), hs-CRP (WMD: -0.95; 95% CI: -1.01 to -0.89, p < 0.001), Neutrophil levels (SMD: -0.46; 95% CI: -0.90 to -0.01, p = 0.043), following zinc supplementation. CD4 level also increased significantly, (WMD: 1.79; 95% CI: 0.57 to 3, p = 0.004). Zinc supplementation had no significant effect on WBC (SMD: -0.66; 95% CI: -1.67 to 0.36, p = 0.204), lymphocyte (WMD: 1.86; 95% CI: -0.86 to 4.58, p = 0.181), monocyte levels (SMD: -0.16; 95% CI: -0.07 to 0.39, p = 0.167), CD3 (SMD: 0.37; 95% CI: -0.49 to 1.22, p = 0.399). CONCLUSION: Zinc supplementation decreased the CRP, hs-CRP and TNF-α, IL-6, neutrophil and increased CD3 and CD4 level significantly.

Key Findings

Zinc supplementation decreased the CRP, hs-CRP and TNF-α, IL-6, neutrophil and increased CD3 and CD4 level significantly.

Outcomes Measured

  • C-reactive protein

Population

Field Value
Population See abstract
Sample Size 1995
Age Range See abstract
Condition See abstract

MeSH Terms

  • Adult
  • Biomarkers
  • C-Reactive Protein
  • Dietary Supplements
  • Humans
  • Immunologic Factors
  • Inflammation
  • Randomized Controlled Trials as Topic
  • Zinc

Evidence Classification

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

Provenance

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