The Claim
Vitamin C supplementation reduces the incidence of the common cold by 50% (relative risk 0.50, 95% confidence interval 0.38 to 0.66) in high-stress populations such as marathon runners, skiers, and soldiers undergoing sub-arctic exercises, based on evidence from 6 trials involving 642 participants.
What the research says
Supports is higher
Support is ahead, but a single strong opposing study can change this.
These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.
Taking vitamin C supplements might cut your chances of getting a cold in half if you're under a lot of physical stress, like running marathons, skiing, or doing tough military training in cold weather.
See the scientific wording
Vitamin C supplementation reduces common cold incidence by 50% (RR 0.50, 95% CI 0.38 to 0.66) in specific high-stress populations including marathon runners, skiers, and soldiers undergoing sub-arctic exercises, based on 6 trials involving 642 participants.
What the research says
1 studyStudy: Vitamin C for preventing and treating the common cold.
The study looked at the same vitamin C use in the same high-stress groups and found exactly what the claim says: it cuts colds by half in those people.
Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.