Ginseng May Enhance Immune Function
June 5, 2000 -- Stop before you pop that ginseng tablet if you're taking it to boost physical endurance. Ginseng seems to enhance certain components of the immune system, but claims that it boosts physical endurance in healthy people do not hold up, according to researchers at the University of Illinois at Chicago.
The term "ginseng" has been applied to more than 30 different species of plants, lead author Gail B. Mahady, PhD, and her colleagues write in a recent issue of Nutrition in Clinical Care. They concentrated on the Korean and Siberian varieties because those have been the focus of most previous studies.
Traditionally, Korean ginseng has been used as a tonic or immune stimulant for people recovering from chronic illnesses. The current practice of promoting it as a performance-booster in people who are already healthy is a "terrible mistake," Mahady tells WebMD.
"It has been used in traditional Chinese medicine in people more to restore health," she says. "It is never used in healthy individuals." Most of the trials showing a beneficial effect of Korean ginseng on physical endurance and capacity were so poorly performed that it is difficult to draw any conclusions from them, she and her co-authors write.
More promising are studies of the effects of Korean ginseng on the immune system. Two trials have shown that in healthy volunteers who take ginseng, certain immune cells are more numerous or more active than in people who take a placebo, or sugar pill.
For example, in a study of patients with bronchitis, a congestive lung disease, ginseng appeared to enhance the function of certain immune components in the bronchi, which are the main airways in the lungs. Mahady and her co-authors suggest ginseng may exert its effects on the body's stress response as well as the immune system.
There is some evidence that ginseng enhances immune activity in patients with AIDS and chronic fatigue syndrome, says Mahady, who is a research assistant professor at the university's College of Pharmacy. However, she tells WebMD that no good studies have yet confirmed its effect. "We really need to look at it in the elderly because there's a lot of chronic illness in that group," she says.