Kicking The Common Cold With Vitamin C - Myth
Taking high doses of vitamin C to cure the common cold does not lower the duration or severity of cold symptoms in healthy Australian adults, according to a study published in the latest edition of the Medical Journal of Australia.
Professor Robert Douglas, Visiting Fellow, and colleagues at the National Centre for Epidemiology and Population Health, Australian National University (ANU), Canberra, sought to determine the effect of large doses of vitamin C in the treatment of the common cold. Their study followed a recent Cochrane review that concluded large maintenance doses of vitamin C (ie, doses taken whether or not the person had a cold) do not lower the incidence of colds, but may shorten the duration of symptoms of any colds that occur by about half a day.
Volunteers were recruited from staff and students of the ANU over 18 - months in 1998 and 1999.
"Our study was a double-blind, randomised trial in 400 healthy volunteers, in which we compared the effects of different doses and formulations of vitamin C.
"We chose as "placebo" a dose of 0.03g per day of vitamin C (about half the recommended minimum daily intake). Participants took this dose or daily doses of 1g, 3g or 3g with additives ("Bio-C") at onset of a cold and for the following two days.
"Our study found no significant differences in severity or duration of cold symptoms between groups who took low-dose and high-dose vitamin C as treatment for the common cold," said Professor Douglas.
Although differences were not significant, the placebo group had the shortest duration of nasal, systemic and overall symptoms and the lowest mean severity score after 14 days.
The researchers concluded by again questioning the worldwide practice of well nourished adults taking mega-dosies of vitamin C to treat the common cold.