Q: Dear Dr. Mao,
Can ginseng effectively prevent the common cold and flu?
A: Although most people in the West think of ginseng as a stimulant, in Eastern Europe ginseng is widely believed to improve overall immunity to illness.
A recent study looked at the potential immune-stimulating effects of Panax ginseng when taken by mouth. Four weeks into the study, all participants received influenza vaccine. The results showed a significant decline in the frequency of colds and flus in the group that took ginseng.
While more research is needed, this study suggests that ginseng may be able to do what echinacea, zinc lozenges, and vitamin C cannot: prevent colds.