Studies have demonstrated several benefits of regular ginseng consumption, including increased energy, stress resistance, and libido. And there is significant scientific support for using ginseng to counter fatigue, improve concentration, and aid recovery from an illness or surgery. However, ginseng has not been proven effective for bolstering the immune system. At least, not yet.

In a recent animal study, ginseng appeared to stimulate the function of certain immune cells to help clear bacterial infection. In another human study, those receiving daily ginseng supplements prior to flu vaccination were less likely to contract the flu than those in the control group, who were administered placebos in addition to the vaccine.

While ginseng has many beneficial uses, right now there's not enough science to back up using ginseng as an immune booster. While new evidence is being sought, help strengthen your immune system and reduce your chance of getting an infection by eating healthy (get lots of fruits, vegetables, and fiber), practicing relaxation techniques to reduce stress (your body is more vulnerable to disease when its under duress), and fighting off colds and flu with the proven immune boosting herbal medicine echinacea.

Immune system: Numerous body parts (for example, white blood cells, bone marrow, the spleen) that work together to destroy germs that have invaded your body and threatened your health.

Libido: sexual drive

Placebo: An inactive compound identical in appearance to a substance being tested for effectiveness. In experimental studies, placebos are administered to one group of people and the substance being tested to another in an attempt to determine whether the recipients are responding to the activity of the substance being tested or only to the suggested benefits of the substance. Persons receiving placebos do not know that they are receiving a placebo instead of the drug.

All About Ginseng (Frequently Asked Questions) by Stephen Fulder (Avery Publishing Group, 1999)

The 10 Best Tools to Boost Your Immune System by Elinor Levy and Tom Monte (Houghton Mifflin, 1997)

Fortify Your Immune System Naturally by Kari Koster-Loesche (Sterling Publishing, 1998)

Ask Dr. Weil web site. "Which ginseng is genuine?" and "Immunity." Available at www.pathfinder.com/drweil. Accessed November 22, 1999.

Blumenthal M, ed. The Complete German Commission E Monographs—Therapeutic Guide to Herbal Medicines. Austin, TX: The American Botanical Council and Boston, MA; Integrative Medicine Communications; 1998: 138–139.

Integrative Medicine Access: Professional Reference to Conditions, Herbs & Supplements. Newton, Mass: Integrative Medicine Communications; 2000.

Scaglione F, Cattaneo G, Alessandria M, Cogo R. Efficacy and safety of the standardised Gingseng extract G115 for potentiating vaccination against the influenza syndrome and protection against the common cold. Drugs Exp Clin Res. 1996;22(2):65–72.

Song ZJ. Ginseng treatment improved the ability of phagocytes in blood and lungs to capture and kill bacteria. Presented at the 99^th General Meeting of the American Society for Microbiology; June 1, 1999; Chicago.