What is reishi? What is it used for?
Reishi is a type of mushroom found in the coastal regions of China. It usually grows on decaying logs and tree stumps, and can be found in six different colors, the most common of which is red. Although it is native to China, reishi is now cultivated in several countries, including the United States, Japan and Korea.
Reishi has been an important component of traditional Chinese medicine for at least 2,000 years. The Chinese name for reishi is ling zhi, which means "herb of spiritual potency." As such, it has been used traditionally to revitalize the spirit and regulate qi, and to treat conditions such as fatigue, weakness and insomnia.
Reishi contains several important chemicals and compounds, including sterols, polysaccharides, triterpenoids, coumarin and mannitol. Ganoderic acids found in reishi (which lead to the mushrooms other name, ganoderma) may lower blood pressure and decrease levels of LDL cholesterol in the blood. The triterpernoids in reishi have been shown to reduce blood platelets from sticking together, which can lower the risk of stroke and coronary heart disease. Other studies suggest reishi may benefit patients who suffer from altitude sickness and hepatitis B, although these studies have yet to be confirmed.
How much reishi should I take?
Most practitioners and herbalists will recommend 1.5-9 grams of dried mushroom per day. As an option, patients can take 1-1.5 grams of reishi powder (1 ml per day taken with tea, or as a tincture).
What forms of reishi are available?
Raw and dried reishi is available at most herbal shops and specialty stores. Some stores may also sell reishi powder, which can be used in teas and tinctures. In addition, reishi extracts may be available.
What can happen if I take too much reishi? Are there any interactions I should be aware of? What precautions should I take?
Reishi is considered safe when taken in the appropriate doses. The American Herbal Products Association has given reishi a class one rating, meaning it can be safely consumed when used appropriately. However, continuous, long-term use (3-6 months or more) may result in dry mouth and dry nasal passages, nose bleeds or upset stomach. Because reishi can decrease the effectiveness of platelets, it should not be taken by people who use anticoagulant medications. It should also be avoided by women who are pregnant or lactating.
As of this writing, there are no well-known drug interactions with reishi. As always, make sure to consult with a licensed health care provider before taking reishi or any other herbal remedy or dietary supplement.
References
- Kammatsuse K, Kajiware N, Hayashi K. Studies on Ganoderma lucidum: I. Efficacy against hypertension and side effects. Yakugaku Zasshi 1985;105:5313.
- Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Foods, Drugs and Cosmetics, 2nd ed. New York: John Wiley & Sons, 1996, pp. 25560.
- McGuffin M, Hobbs C, Upton R (eds.) American Herbal Products Associations Botanical Safety Handbook. Boca Raton, FL: CRC Press, 1997, p. 55.
- Shu HY. Oriental Materia Medica: A Concise Guide. Palos Verdes, CA: Oriental Healing Arts Press, 1986, pp. 6401.
- Teeguarden R. Radiant Health: The Ancient Wisdom of the Chinese Tonic Herbs. New York: Warner Books, 1998, pp. 88-95.