What’s better for a cold: vitamin C or echinacea? — Rob C., St. Louis, MO

The sheer breadth of scientific literature supporting vitamin C’s ability to fight the common cold could fill a small library. Indeed, a recent study found that people who took 500 milligrams of vitamin C daily had 34 percent fewer colds than those who took less. The number of studies devoted to echinacea, on the other hand, wouldn’t fill a three-ring binder.Bottom line: Choose either vitamin C or Ester-C (a nonacidic version of vitamin C that’s gentler on the stomach).

— Mark Moyad, MD, the Phil F. Jenkins director of preventive and alternative medicine at the University of Michigan Medical Center

Live Your Best Life Every Day

Get Our Daily Newsletter

Sign up