The Efficacy of Multivitamin, Vitamin A, Vitamin B, Vitamin C, and Vitamin D Supplements in the Prevention and Management of COVID-19 and Long-COVID: An Updated Systematic Review and Meta-Analysis of Randomized Clinical Trials

source extracted confidence: high 2026-04-09
#humans #dietary-supplements #covid-19 #vitamins #vitamin-d

The Efficacy of Multivitamin, Vitamin A, Vitamin B, Vitamin C, and Vitamin D Supplements in the Prevention and Management of COVID-19 and Long-COVID: An Updated Systematic Review and Meta-Analysis of Randomized Clinical Trials

Sinopoli et al., 2024 | Nutrients | Meta Analysis

Citation

Sinopoli Alessandra, Sciurti Antonio, ... Baccolini Valentina. The Efficacy of Multivitamin, Vitamin A, Vitamin B, Vitamin C, and Vitamin D Supplements in the Prevention and Management of COVID-19 and Long-COVID: An Updated Systematic Review and Meta-Analysis of Randomized Clinical Trials. Nutrients. 2024-Apr-29;16(9). doi:10.3390/nu16091345

Abstract

This review aims to evaluate the efficacy of any vitamin administration(s) in preventing and managing COVID-19 and/or long-COVID. Databases were searched up to May 2023 to identify randomized clinical trials comparing data on the effects of vitamin supplementation(s) versus placebo or standard of care on the two conditions of interest. Inverse-variance random-effects meta-analyses were conducted to estimate pooled risk ratios (RRs) and 95% confidence intervals (CIs) for all-cause mortality between supplemented and non-supplemented individuals. Overall, 37 articles were included: two regarded COVID-19 and long-COVID prevention and 35 records the COVID-19 management. The effects of vitamin D in preventing COVID-19 and long-COVID were contrasting. Similarly, no conclusion could be drawn on the efficacy of multivitamins, vitamin A, and vitamin B in COVID-19 management. A few positive findings were reported in some vitamin C trials but results were inconsistent in most outcomes, excluding all-cause mortality (RR = 0.84; 95% CI: 0.72-0.97). Vitamin D results were mixed in most aspects, including mortality, in which benefits were observed in regular administrations only (RR = 0.67; 95% CI: 0.49-0.91). Despite some benefits, results were mostly contradictory. Variety in recruitment and treatment protocols might explain this heterogeneity. Better-designed studies are needed to clarify these vitamins' potential effects against SARS-CoV-2.

Key Findings

Better-designed studies are needed to clarify these vitamins' potential effects against SARS-CoV-2.

Outcomes Measured

  • Requires manual extraction

Population

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

MeSH Terms

  • Humans
  • Dietary Supplements
  • COVID-19
  • Vitamins
  • Vitamin D
  • Randomized Controlled Trials as Topic
  • Ascorbic Acid
  • SARS-CoV-2
  • Vitamin A
  • COVID-19 Drug Treatment
  • Vitamin B Complex

Evidence Classification

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

Provenance

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