Ginseng is one of the most popular of the commonly used herbs in the United States today. This slow-growing perennial has been used medicinally in Asia for more than 2,000 years. Asian ginseng (Panax ginseng) grows throughout Korea, China, and Japan, while American ginseng (Panax quinquefolius) grows throughout the eastern region of North America. Ginseng is relatively expensive since it is quite difficult to grow. Normally it takes the ginseng root about four to six years to reach maturity.
The scientific name of ginseng, Panax, is derived from two Greek words, pan (“all”) and akos (“cure” or “remedy”), clearly reflecting the root’s reputation as a panacea or cure-all. The ginseng root, which has the characteristic appearance of a human body with arms and legs protruding, conveys to some people that ginseng should be a panacea for all human ills. The name ginseng itself is a transliteration of Chinese ideograms that mean “the essence of the earth in the form of man.”
There are many types and grades of ginseng, depending upon the maturity of the root, the part of the root used, and the geographical origin of the plant. The air-dried form of ginseng is called white ginseng. Red ginseng is produced when the root is steam-treated and then dried. The medicinal part of ginseng is the dried main root and the lateral roots and root hairs.
Varied Historical Uses
Ginseng has traditionally been used for the treatment of anxiety and agitation, mental fatigue and debility, tiredness, and an inability to concentrate, especially in the elderly. In the past some have used it as a tonic or to boost their energy. Ginseng is also considered an adaptogen to help one cope with stress. A number of European countries do list ginseng in their official pharmacopeias.
A number of Soviet and European researchers have shown that Asian ginseng extract may increase work efficiency, improve reaction times, and enhance adaptation to environmental changes and stresses. There is, however, a lack of compelling evidence to support the claim that ginseng can enhance athletic performance or reduce fatigue in humans.
There is a decrease in the risk of cancer associated with an increased frequency and duration of using ginseng. Recent Korean studies suggest that the use of Asian ginseng reduces the risk of several types of human cancer by 45 to 85 percent. Ginseng extract and powder were found to be more effective than fresh sliced ginseng or ginseng tea in reducing the risk of cancer.
In another Korean study the incidence of human cancer was seen to decrease steadily with increasing use of ginseng. Those who had taken ginseng for one year had 36 percent less cancer than nonusers, while those who used ginseng for five years or more had 69 percent less cancer. In addition, those who had used ginseng less than 50 times in their life had 45 percent less cancer, while those who used ginseng more than 500 times in their life had 72 percent less cancer.
Ginseng seemed to be most protective against cancer of the ovaries, larynx, pancreas, esophagus, and stomach; and less effective against breast, cervical, bladder, and thyroid cancers. Other research showed that the ginsenosides in ginseng inhibited cell growth in prostatic tumors. Polysaccharides and polyacetylenes in ginseng have also exhibited cancer-protective effects.
Ginseng may exert a blood glucose lowering effect and has been reported to contain a peptide that mimics the action of insulin. When three grams of ginseng were taken with an oral glucose challenge, a 20 percent reduction in the blood-sugar response was observed in subjects with Type II diabetes. Ginseng therapy can also reduce fasting blood sugar levels in patients with diabetes. Further clinical tests are needed to study the efficacy of long-term administration of ginseng.
Animal studies also suggest that ginseng mildly inhibits platelet clumping and may dilate blood vessels. Korean red ginseng may be useful for patients with hypertension, but more clinical
trials are needed.
Ginsenosides Are Active
The major active ingredients of ginseng root are considered to be a family of about 30 triterpene saponins called ginsenosides. Ginseng products vary in the amount of ginsenosides they contain. Commercial ginseng products typically are standardized to contain about 4 to 7 percent ginsenosides. The different ginsenosides have different actions, from mild antiinflammatory activity to nonspecific immunostimulant activity. Because of the complex composition of ginseng and the scarcity of good human clinical trials, there is uncertainty regarding the value attributed to ginseng.
Ginseng often suffers from a lack of standardization and product quality. This lack of standardized preparations of ginseng has added to the difficulty of defining its health benefits. Some ginseng products may actually contain negligible amounts of ginseng. When Consumer Reports analyzed 10 different brands of ginseng, they found a wide variation in the content of ginsenosides, from 0.4 milligrams/capsule in one brand to 23.2 milligrams/capsule in another brand.
Ginseng capsules or tablets usually provide about 100 to 400 milligrams of dried extract, equivalent to 0.5 to 2 grams of ginseng root per day. Generally there are no side effects observed with the use of ginseng. It is suggested that for effectiveness, ginseng be used no longer than three months and then discontinued for one month. Ginseng is contraindicated with stimulants, including the excessive use of caffeine-containing foods and beverages. The safety of use during pregnancy has not been established.
Remember: Herbal products and dietary supplements can have pharmacological effects, may produce adverse reactions in some people, and could interact with over-the-counter and prescription medications you may take. Discuss with your physician your decision to use any herbal product. Anything mentioned in this article is not intended to diagnose, prescribe, or treat any ailment.
Winston J. Craig, Ph.D., R.D., is a professor of nutrition at Andrews University, Berrien Springs, Michigan.