The herb with a thousand faces
For: Better Sex in a Bottle?, September
2002
Ginseng (species Panax) has been used medicinally for thousands of years. People take it as a pepper-upper and to cure a wide range of ills. In this country alone its sales run into hundreds of millions of dollars annually. One well-known website advertises ginseng to treat 12 different ailments, from the common cold to HIV infection and Alzheimer's disease. Fruit shake bars all over the country will add ginseng to your smoothie. Deli refrigerators are full of ginseng-enriched teas and other soft drinks. Kids too young to buy beer can purchase ginseng elixirs laced with alcohol at convenience stores.
Thousands of books and papers on ginseng have been published—way too many, according to Dr. Varro Tyler, the leading American expert on herbs and plant-based medicine. Scientists are still largely in the dark about the medicinal benefits of ginseng. But at least its chemical properties have been studied thoroughly. The plant's active ingredients are called ginsenosides (among other terms), and 13 different types are known. But like most plants, ginseng contains many other compounds, too—volatile oils, sugar, fats, B vitamins, minerals, plant hormones, and a range of other active substances. It's not so simple to figure out which of these elements are the important ones.
Where it comes from
What's actually in any product labeled ginseng depends on at least two things: first, what part of the plant it came from—leaves, roots, or stems, all of which have different chemical compounds. Second, there are at least three types of ginseng with different biological properties. American ginseng (Panax quinquefolius) is on the endangered species list here, so intensively has it been cultivated and harvested as a cash crop. Korean or Asian ginseng (Panax ginseng) is grown all over Asia and also has other names. Siberian ginseng (Eleutherococcus senticosus) contains still other chemicals and is not regarded as a true ginseng. And there are other kinds, too. In addition, ginseng comes in two general types, red and white, depending on how it was processed.
Since most studies have been of poor quality, we still don't know if ginseng works or how to use it. "Most of the literature in this area," Dr. Tyler says, "is based more on superstition and subjective opinion than on objective, scientific evidence." Various researchers have claimed that ginseng boosts energy and athletic performance; that it prevents or reduces the risk of all kinds of cancer; that it fights emotional stress, enhances memory, boosts immunity, reduces blood sugar in diabetics, and promotes sexual potency and desire. It's often referred to as an "adaptogen," with claims that it promotes health, energy, and a sense of well-being, like the tonics of yore. But this is a meaningless term.
Quality control vs. out-of-control
The few well-designed studies on the subject have not borne out claims that ginseng boosts athletic performance or energy. (You won't find this out from manufacturers' websites or catalogues.) Among other research, a well-designed study of 36 healthy men, published in the Journal of the American Dietetic Association in 1997, found that ginseng did not improve physical performance. There's preliminary evidence suggesting that the plant may help diabetics, but studies with purified extracts of ginseng have not found a benefit for them. Which brings up another problem: obtaining authentic ginseng in standardized doses is difficult, and many studies do not specify what they used. The best grades of ginseng are very expensive. And the herb is easily contaminated with other plant substances that may affect the outcome of trials.
That's also the problem with ginseng in the marketplace: a complete lack of quality control. You may pay for ginseng and not get any. Dr. Tyler has reported that of 54 commercial ginseng products analyzed by independent researchers, 60% contained little ginseng, and 25% had none at all. Other studies have found that commercial ginseng products vary widely in the specific ginsenosides they contain, and some have none. As reported in the Lancet in 1994, one so-called ginseng product, sold by National Health Products in this country, actually contained ephedrine instead of ginseng. The Swedish athlete who used it ended up testing positive for "doping."
A modest proposal: There's no consistent evidence to support the use of ginseng. A recent thorough review in the European Journal of Clinical Pharmacology came to this conclusion, and called for more rigorous investigations with real, standardized ginseng. Dr. Tyler proposes that the supplements makers and the various governments that make so much money out of selling, growing, importing, and exporting ginseng should turn back some of their profits toward this objective. But in the marketplace as it currently exists, they have little motivation to do so.
UC Berkeley Wellness Letter, July 2000
