The Claim

Vitamin C supplementation at doses of 1 gram per day or higher reduces the severity of common colds by 15% (95% confidence interval 9–21%) in healthy individuals, as determined by a pooled analysis of 15 comparisons from 10 randomized controlled trials.

Source: Vitamin C reduces the severity of common colds: a meta-analysis

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
39score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Cause and effect
1 study reviewed
In plain English

Taking vitamin C pills every day might make your colds less severe, according to some studies that looked at healthy people.

See the scientific wording

Vitamin C supplementation at doses ≥1 g/day reduces the severity of common colds by 15% (95% CI 9–21%) in healthy individuals, based on pooled analysis of 15 comparisons from 10 randomized controlled trials.

What the research says

1 study
  1. Study: Vitamin C reduces the severity of common colds: a meta-analysis

    This study looked at the same vitamin C dose and same group of people as the claim, and found exactly the same 15% reduction in cold severity, so it supports the claim.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.