Vitamin C supplementation reduces the odds of developing a common cold in Republic of Korea Army recruits: randomised controlled trial

Kim TK, Lim HR, Byun JS

Published in BMJ Military Health, Vol. 168, pp. 117-123

Methodology

Randomised, double-blind, placebo-controlled trial in 1444 Korean Army recruits during 30 days of basic training; 695 received 6000 mg/day vitamin C and 749 placebo, with common cold diagnosis taken from military medical records.

Key Findings

The vitamin C group had a 0.80-fold lower risk of getting a common cold than the placebo group, with stronger effects among never smokers and one training camp.

Conclusions

High-dose vitamin C reduced the odds of common cold in young men under heavy physical stress, consistent with the Cochrane subgroup finding.

Limitations

Very high 6000 mg/day dose not typical of consumer use; outcome ascertained from medical records rather than symptom diaries; single military population.