Ginseng

For the past two decades, ginseng has been touted as the "wonder herb." Many athletes swear that it gives them a competitive edge, and millions of others use it as an adaptogen. A term coined by a Soviet scientist in the 1940s, an adaptogen is a class of agents that helps the body adjust to stresses of various kinds, whether it be heat, cold, exertion, trauma, infection, or psychological stress. As an adaptogen, ginseng is purported to help control diabetes, enhance immunity, stimulate the mind, generate an overall sense of well being, and improve athletic performance.

How It Works

There are several types of ginseng. One is the native Asian variety (Panax ginseng). Closely related is American ginseng (Panax quinquefolius), and, finally, the third type is Siberian ginseng (Eleutherococcus senticosus). The American and Asian varieties are the two major types of ginseng, and both have a similar chemical makeup. Siberian ginseng, on the other hand, differs slightly and is classified as a distant cousin.

The active ingredients in all types of ginseng are a set of compounds called ginsenosides. Approximately thirty of these compounds have been identified, and they appear to be responsible for ginseng's mechanism of action. What ginsenosides do specifically in the human body, however, eludes researchers. Many of the studies seem to yield contradictory results. Some of this may stem from the variation in growing conditions and processing of the herb; however, the ginsenosides themselves have differing and sometimes opposing actions. Ginsenoside Rb1, for example, seems to lead to sedation and lower blood pressure, while ginsenoside Rg1 acts as a stimulant and raises blood pressure.

What It Might Do For You

Despite all the confusion, the most common use of ginseng is as an adaptogen. Many studies have examined ginseng and its effect on animals under conditions of extreme stress. The results suggest that ginseng may trigger physiological changes that help the body adapt to adverse conditions. For instance, when it comes to athletic performance, some studies suggest that ginseng may enhance work capacity by improving the supply of oxygen to muscles, increasing aerobic capacity, reducing lactate levels in the blood, and lowering heart rates during exercise. As for immune function, a handful of studies in mice found that consuming ginseng before exposure to a virus significantly increased the survival rate and the number of antibodies produced. Nevertheless, other studies found no significant effect.

In addition to enhancing immunity and athletic performance, ginseng may hold promise in managing some forms of chronic disease. For example, in three double-blind studies, ginseng improved blood sugar control in diabetics. It has also been found to help lower cholesterol, presumably by accelerating its metabolism and removal from the body. Additionally, some ginsenosides act as anticoagulants, which can keep blood platelets from aggregating and forming clots.

And, finally, ginseng may improve some aspects of mental function. One study, for instance, showed the herb improved abstract thinking; however, there was no significant change in reaction time, memory, concentration, or overall subjective experience between the study and control groups.

Potential Side Effects

At usual dosage levels, side effects are unlikely. Breast pain and postmenopausal vaginal bleeding have occasionally been reported. Other possible side effects include insomnia, headaches, nervousness, nosebleeds, and vomiting.

Herb-Drug Interactions

Before taking ginseng, discuss it with your healthcare provider, as the herb seems to interact with many different medications. For instance, those taking anticoagulants such as Coumadin, aspirin, Plavix, or Ticlid should avoid ginseng, as it seems to decrease the drugs' effects. (See the Herbal Spotlight overview for a comprehensive list of herbs that also act as anticoagulants and may be contraindicated if combined with ginseng).

Additionally, those taking MAO inhibitors should avoid ginseng all together as it is reported to cause manic episodes. Also, people taking insulin or oral hypoglycemics (Prandase, Precose, Dymelor, Diabinese, Amaryl, Glucotrol, DiaBeta, Glynase, Micronase, Glucophage, Glyset, Actos, Avandia, Prandin, Tolinase, Orinase, Rezulin) need to exercise caution with ginseng as it may decrease your dosage need.

Principal Author

Stefanie Perelman, M.S., R.D., holds a B.A. in journalism from the University of Wisconsin-Madison and a master's in clinical dietetics from New York University. A registered dietitian, she presently works at Montefiore Medical Center in the Bronx and is available for private consultation.

Nutrition Editor

Donna Tinnerello MS, RD, CD/N is registered dietitian with more than 10 years experience in HIV and nutrition. She works in lower Manhattan at Cabrini Medical Center, the community and in private practice. Her subspecialties are cardiovascular, renal, gastrointestinal disease, diabetes and weight loss. Donna is available for private consultation by referral only.