Ginseng (Panax) is a genus of about five or six species of slow-growing perennial plants with fleshy roots, in the family Araliaceae. They grow in the Northern Hemisphere in eastern Asia and North America, typically in cooler climates; Panax vietnamensis, discovered in Vietnam, is the southernmost ginseng found. Ginseng is characterized by the presence of ginsenoside.

Siberian Ginseng (Eleutherococcus senticosus) is not considered a true ginseng; instead of a fleshy root, it has a woody root; instead of ginsenosides, eleutherosides are present.

Some other species previously classified in Panax are now treated in the separate genera Polyscias and Pseudopanax.

History

The English word ginseng derives from the Chinese term Ren Shen (??), literally "man root" (referring to the root's characteristic forked shape, resembling the legs of a man). It was originally the common name for several plants valued for their medicinal properties; although ginseng is now most often associated with the genus Panax, some researchers believe that the original ginseng used in ancient China may have been a different plant. Although ginseng is often seen as an East Asian medicine, American ginseng has been used by Native Americans for centuries. A wide variety of ginseng is generally available in many Chinatown herb shops and ethnic Chinese supermarkets.

Modern science and ginseng

The positive medicinal effects of ginseng have been difficult to prove using modern science. Frequently, there are contradictory results from different studies. Supporters claim that this is due to the wide variety of ginseng quality used in studies. The quality and neutrality of studies from East Asia have also been questioned. Another issue is that there is no profit to be achieved from researching ginseng because it cannot be patented; therefore, pharmaceutical companies have no incentive to research ginseng. As a result, quality studies into the effects of ginseng are rare. Ironically, one of the better studies involving ginseng actually uses a proprietary formula of ginseng

Ginseng is highly prized as an adaptogen (a product that does no harm, but increases the body's resistance to stress). Unfortunately, this property is extremely difficult to prove scientifically as well.

A comparative, randomized and double-blind government study does indicate it to be "a promising dietary supplement" when assessed for an increase in quality of life.

Panax ginseng appears to inhibit some characteristics associated with cancer in animal models; nevertheless, this effect is unclear in humans .

Common classification

• Panax ginseng Chinese/Korean ginseng (root)

Alleged effects: promotes Yang energy, improves circulation, increases blood supply, revitalizes and aids recovery from weakness after illness, stimulates the body

The ginseng root can be double steamed with chicken meat as a soup. (See samgyetang.)

• Panax quinquefolius American ginseng (root)

Ginseng that is produced in the United States and Canada is particularly prized in Chinese societies, and many ginseng packages are prominently colored red, white, and blue.

Alleged effects: promotes Yin energy, cleans excess Yang in the body, calms the body. The reason it has been claimed that American ginseng promotes Yin (shadow, cold, negative, female) while East Asian ginseng promotes Yang (sunshine, hot, positive, male) is that, according to traditional Chinese medicine, things living in cold places are strong in Yang and vice versa, so that the two are balanced. Chinese/Korean ginseng grows in northeast China and Korea, the coldest area known to Chinese in the old time, so ginseng from there is supposed to be very Yang. And originally, American ginseng was imported to China from subtropical Canton, the seaport next to Hong Kong, so Chinese doctors believed that American ginseng must be good for Yin, because it came from a hot area. However they did not know that American ginseng can only grow in temperate regions.

The ginseng is sliced, a few slices are soaked in hot water to make a tea.

Most American ginseng is produced in the Canadian provinces of Ontario and British Columbia and the American state of Wisconsin, according to Agri-food Canada. P. quinquefolius is now also grown in northern China.

A randomized, double-blind study shows that American ginseng reduces influenza cases in the elderly when compared to placebo.

Wild ginseng

Wild ginseng is ginseng that is not cultivated, rather, it is harvested from nature. Wild ginseng is relatively rare, and in many cases threatened or endangered. Wild ginseng has been shown to contain higher levels of ginsenoside.

Red ginseng

Red ginseng is Panax ginseng that has been heated, either through steaming or sun-drying. This version of ginseng is associated with stimulating sexual function and anti-cancer benefits. In this context, regular, non-heated ginseng is referred to as White ginseng.

A double-blind, crossover study of Red ginseng's effects on impotence show a marked positive effect.

A study shows that Red ginseng reduces the relapse of gastric cancer versus control.

A study of ginseng's effects on rats show that while both White ginseng and Red ginseng reduce the incidence of cancer, the effects appear to be greater with Red ginseng .

Ginseng alternatives

These plants are sometimes referred to as ginseng, but they are either from a different family or genus.

• Siberian ginseng (Eleutherococcus senticosus)
• Prince ginseng (Pseudostellaria heterophylla)
• Female ginseng (Angelica sinensis, aka Dong Quai)
• Indian ginseng (Withania somnifera, aka Ashwagandha)
• Brazilian ginseng (Pfaffia paniculata)
• Peruvian ginseng (Lepidium meyenii, aka Maca)
• Southern ginseng (Gynostemma pentaphyllum, aka Jiaogulan)