Vitamin C has been believed, over the years, to be a potential cure against the common cold. The belief has now been proved to be true by researchers who have studied changes in immune cells' response to vitamin C. The researchers reported that in their study of 12 healthy subjects who took one gram of vitamin C a day for two weeks, they found a boosted immune system response in all of them during the period. Their finding(in two patients) that the response to vitamin C took place within five hours indicated that taking vitamin C at the first signs of a cold could help ward it off.
The researchers took blood samples of the subjects before and after taking vitamin C and separated and measured the levels of the immunity boosting substances called cytokines. They found that the levels of certain virus-fighting cytokines was increased in the period immediately after the two weeks and came back to normal after about two weeks. This proved that the effect of vitamin C is short-lived. The researchers also added that contrary to the belief that several grams of vitamin C in a day has toxic effects, they found no toxic side-effects in their subjects who were given double the recommended daily allowance.
Stephen Tilles, MD, with the Northwest Asthma & Allergy Center in Seattle, said that the study legitimizes the beneficial effects of vitamin C as it had measured the effect at the level of the immune system cells.