Rekindling an old debate, researchers at the University of Wisconsin have found that large doses of Vitamin C may reduce the severity of the common cold.
Elliot Dick, a professor of preventive medicine, presented his team's findings Thursday morning at an international symposium on medical virology in Anaheim.
Medical researchers have been debating the efficacy of Vitamin C since at least 1970, when scientist Linus Pauling declared that megadoses of the vitamin would prevent or lessen symptoms of the common cold.
Pauling the Advocate
Pauling won the Nobel Peace Prize in 1962 and the Nobel Prize for chemistry in 1954, for work unrelated to Vitamin C. At 86, he is still one of the vitamin's strongest advocates, consuming 18 grams a day and boosting that to 60 grams a day "when he feels a cold coming on," his secretary, Dorothy Munroe, said this week. (According to the National Research Council of the National Academy of Sciences, the recommended dosage for Vitamin C is 60 milligrams a day.)
Over the years, researchers from Toronto, Pittsburgh and the National Institutes of Health in Bethesda, Md., have disputed Pauling's claims for the vitamin and described its impact on colds as "clinically insignificant."
In an interview this week, Dick said he still needs to conduct several more field trials before he can convince the skeptics.
Still, he said, his experiment last spring showed that "Vitamin C sharply reduced the signs and symptoms of a cold" and also reduced the likelihood that the cold would be transmitted to someone else.
Early in April, Dick and three researchers began giving eight student volunteers two grams of Vitamin C a day, administered in four doses of 500 milligrams each. At the same time, the researchers gave placebos to a control group of eight students.
After 3 1/2 weeks of the megadoses, Dick moved his 16 volunteers into a dorm with eight sneezing, wheezing men who had been infected in his lab with a rhinovirus.
As Dick and his researchers watched and counted sneezes, the 16 volunteers spent the next week in close contact with the cold sufferers--playing poker and watching TV with them, eating all meals together and sleeping in adjacent bunks.
One Group Less Sick
Dick's findings: Six of the eight students in the placebo group got colds, as did six of the eight students who took Vitamin C. But students in the Vitamin C group were sick for an average of just seven days, whereas students who received the placebo were sick longer--for an average of 12.3 days.
In addition, Dick said, students in the Vitamin C group had significantly milder symptoms than the placebo group. In the seven-day period that cold sufferers and volunteers lived together, Dick's researchers counted 1,053 coughs, 49 sneezes and 127 nose blows in the placebo group, compared with just 334 coughs, 29 sneezes and 97 nose blows from the Vitamin C group.
Dick, who has studied colds since 1957 and heads UW's Respiratory Virus Research Laboratory, said he will need more experiments to learn whether Vitamin C must be taken daily to lessen the impact of a cold, or whether it could be effective if taken only at the onset of cold symptoms.
But until he reproduces the experiment, Dick admitted, "A lot of people will be trying to shoot us down."