Runners may finally be able to win the runny nose race with the help of vitamin C. The latest update to the Cochrane Review, reported that, although there is no new evidence that regular supplementation with vitamin C can reduce either the severity of symptoms or the duration of the common cold, people under heavy physical stress (runners, swimmers, skiers, etc.) may derive some benefit.
The Cochrane Reviews
The Cochrane Collaboration was formed in 1993 to systematically organize the medical literature in the interest of evidence-based medicine. The collaboration was named after Archie Cochrane (1909-1988), a Scottish doctor and pioneer of the gold standard of clinical research, the randomized controlled trial (RCT). Cochrane reviewers systematically evaluate high-quality RCTs to find answers to clearly-formulated questions such as the title of this article.
Vitamin C (aka ascorbic acid or ascorbate) is actually a group of water-soluble molecules that act as co-factors in eight known enzymic reactions in the human body. One of these reactions is the synthesis of collagen, the main constituent of connective tissue and the most abundant protein in mammals. It is also an excellent anti-oxidant, good for mopping up those pesky free radicals that are the byproduct of so many chemical reactions in the body and the main culprit behind the visible signs of aging.
Linus Pauling (1901-1994), double winner of the Nobel Prize, proposed in 1970 that megadoses of vitamin C could cure the common cold. He was also a pioneer in the sciences of quantum chemistry and molecular biology. Pauling disagreed with the body of scientific literature that did not support the hypothesis that mega-dose treatment with Vitamin C could boost the body’s ability to fight different types of infection, among them the common cold.
The common cold
In developed countries, the common cold is one of the main reasons why people take time off from work or school and why we visit the doctor. There are more than 200 different viruses that can cause the miserable symptoms of a cold, i.e., sneezing, runny nose, cough, congestion, watery eyes, cough and fever. Colds spread from person to person. Because it is a viral infection, antibiotics are useless. Hence, the widespread interest in finding a cure.
The Cochrane update
The reviewers looked at 29 clinical trials involving a combined total of 11,306 participants. In these studies, vitamin C was compared with placebo. The reviewers concluded that vitamin C has no effect on the incidence of common cold in the general population. However, five randomized trials showed vitamin C reduced the frequency of colds by 50 percent in people who engaged in vigorous exercise. So if you regularly engage in sports or other strenuous physical activities, consider adding a high-quality natural vitamin C supplement to your diet in order to reduce the likelihood of colds.
The Cochrane Collaboration [online] https://www.cochrane.org/cochrane-reviews
Chalker E, Hemila H, “Vitamin C for preventing and treating the common cold (Review)” The Cochran Library. 2013