Vitamin C and Colds: Separating Fact from Fiction with a Meta-Analysis

Abstract

Objective: This meta-analysis evaluates the efficacy of vitamin C supplementation in reducing the incidence and duration of the common cold.

Context: Vitamin C has been proposed as a preventive and therapeutic agent for the common cold, but its effectiveness remains controversial, with mixed results from individual studies.

Methods Used: A systematic search of electronic databases was conducted to identify randomized controlled trials investigating the effect of vitamin C supplementation on the common cold. Data were extracted and pooled for meta-analysis.

Researchers' Summary of Findings: In the general population, vitamin C supplementation did not significantly reduce the risk of developing a cold (relative risk = 0.97, 95% CI: 0.94-1.00). However, in subgroup analyses, vitamin C shortened the duration of colds by 8% in adults and 14% in children.

Health Implications: While vitamin C supplementation may not prevent the common cold in most individuals, it appears to modestly reduce the duration of cold symptoms, particularly in children. This supports the use of vitamin C as a potential therapeutic agent for the common cold.

DOI: 10.1007/s00394-017-1563-z