In 1970 Linus Pauling claimed that vitamin C prevents and alleviates the episodes of the common cold. Pauling was correct in concluding from trials published up till then, that in general vitamin C does have biological effects on the common cold, but he was rather over-optimistic as regards the size of benefit. His quantitative conclusions were based on a single placebo-controlled trial on schoolchildren in a skiing camp in the Swiss Alps, in which a significant decrease in common cold incidence and duration in the group administered 1 g/day of vitamin C was found. As children in a skiing camp are not a representative sample of the general population, Pauling's extrapolation to the population at large was too bold, erring as to the magnitude of the effect. Nevertheless, Pauling's general conclusion that vitamin C has physiological effects on the common cold is of major importance as it conflicts with the prevailing consensus that the only physiological effect of vitamin C on human beings is to prevent scurvy.