People have been searching for centuries for a way to prevent colds. That, we’ve been told, was one of the motivations for dosing children with cod liver oil in the 19th and early 20th centuries.
None of the techniques that people have so far invented to prevent colds is completely foolproof, but there are a few that appear to reduce the risk of sniffles and sneezes. Exercise makes a difference, as this New York Times article points out. (It was based on a study published in Scientific Reports, online Nov. 6, 2015.) Getting adequate sleep goes hand in hand with exercise to keep the immune system functioning well.
What About Supplements to Prevent Colds?
Q. You wrote about how to avoid colds. I am in excellent health, get an adequate amount of sleep, exercise every other day and wind up getting just one minor cold per year.
I believe this is due to taking vitamin C and zinc daily, as well as my habitual exercise. When I feel a cold coming on, I take a couple of zinc lozenges that day and the cold never materializes!
Zinc to the Rescue:
A. Zinc is essential for the immune system to function optimally. Older people, vegetarians and those taking diuretics and ACE inhibitor blood pressure pills such as lisinopril may be low in this crucial mineral.
A recent study of older people with low zinc levels found that after three months of supplementation with zinc (30 mg/day) they had more T cells and the cells were more active in responding to a simulated infection (American Journal of Clinical Nutrition, online Jan. 27, 2016). This doesn’t prove that extra zinc can prevent colds, but it suggests that’s a strong possibility.
Be careful not to get too much zinc. We don’t suggest exceeding about 50 mg daily for most people and limiting supplementation to cold season. Those listed above might need more zinc, but too much zinc can cause a copper deficiency.
As for vitamin C, there was some promising research done in the 1990s, but we could find nothing very recent. A dose of about 200 mg/day is probably enough for most folks. When a cold is coming on, that could be taken a few times a day.