Q. I recently heard of something amazing called Coriolus versicolor. It's natural and said to have so many health benefits that I wondered why I haven't heard of it before. Can you give me the lowdown, explain what it is, and what it's used for?

A. Coriolus versicolor, also known as turkey tail, is a mushroom with a long and colorful history as a healing agent. It has been used medicinally for thousands of years, and its properties have been familiar to many cultures. First recorded during the Ming dynasty of China, coriolus has traditionally been used in Chinese medicine to increase energy, reduce phlegm and treat a wide range of conditions including hepatitis, cancer and pulmonary infections. It also has been well known in Japan, where it has long been used as a remedy for cancer.

Coriolus can be found growing in many parts of the world, including the United States. It typically appears in temperate forests on logs and stumps, and on the sides of tree trunks. A visually striking mushroom, its overlapping fan-shaped "fronds" grow in a distinctive radial pattern, with concentric rings of alternating bands of color that vary from dark brown and gray-green to burgundy-orange and white. (Versicolor means "variously colored.") The mushroom's surface has a unique, soft texture often described as velvety to the touch.

Conventional Western medicine did not "discover" the healing properties of coriolus until relatively recently. In the 1960s, chemists working for pharmaceutical companies began to develop an extract from the mushroom for the treatment for cancer. The extract, known as polysaccharide-K (PSK for short), has since become a leading anticancer and chemoprotective compound, and has significantly increased survival rates in cancer patients. PSK led to the development of another extract of the mushroom known as polysaccharide-peptide (also known as PSP).

There has been a wealth of research on coriolus, and many modern studies have confirmed the powerful immunity-enhancing effects of PSK and PSP. A scientific review by the M.D. Anderson Cancer Center found that these polysaccharides have these properties: