To kill a cold: What the research says

Is that vitamin C or echinacea you take during cold season really doing anything? Yes it is, say researchers in recent studies. At the Herbal Health Centre in the UK, 168 volunteers were given either a placebo or vitamin C supplement for two months during cold/flu season. The volunteers were assessed frequently and asked to keep health diaries. Compared to the placebo group, the vitamin C group had significantly fewer colds (37 vs 50) and fewer sick days (85 vs 178). In addition, once a cold started, the vitamin C groups’ symptoms decreased in an average of 1.8 days versus 3.1 days for the placebo group.

Researchers have also made interesting discoveries about the effects of vitamin C megadoses. In one study, 463 students, aged 18 to 32 years, were divided into two groups: a “drug” group and a “vitamin C” group. The drug group was given over-the-counter decongestants and pain relievers when they caught a cold or flu. The vitamin C group was treated with hourly doses of 1,000 mg of vitamin C for the first six hours, and then three doses daily thereafter, after catching a cold or flu. In the vitamin C group, cold and flu symptoms decreased by 85% compared to the drug group.

In a related study, researchers in Germany investigated herbal remedies that might offer early improvement of cold or flu symptoms. Using 15 research centres in this placebo-controlled study, patients who reported cold symptoms were given three tablets daily for seven to nine days of a combination echinacea formula. Of the 238 patients, 55.3% in the herbal group versus 27.3% in the placebo group noticed a decrease in symptoms. The largest improvement was seen for patients who took the herbal medicine immediately upon the first sign of symptoms.

Sources: Adv Ther 2002 May-Jun;19(3):151-9; J Manipulative Physio Ther 1999 Oct;22(8):530-3; Curr Med Res Opin 1999;15(3):214-27