Everyone gets colds, and they're no fun. At one point or another, most of us have tried a home remedy to prevent a cold or speed up the recovery process. But do they work? Aaron Carroll took a look at the cold-treatment and -prevention evidence for echinacea, garlic, vitamin C, zinc, Airborne, and chicken soup. All of them either have studies showing little or no positive effect, or have not been studied at all.
Most of these are at least harmless, with the exception of zinc. Nasal spray formulations containing zinc can permanently damage your sense of smell, leading one manufacturer to settle a class-action lawsuit for $12 million.
Chicken soup, on the other hand, may be associated with memories of kindly grandmothers, and is clinically proven to prevent starvation. So if you're looking for a cold remedy, that at least won't cause any lasting damage. --Ryan Cooper