Home > Total Nutrition > Supplements for Health and Healing

Supplement Savvy for Cancer: Japanese Mushrooms

By Jill Place, MA, RD

What They Are . . .

There's a host of Japanese mushrooms that may boost immunity, prevent cancer, and decrease the toxic effects of chemotherapy. The most active substance in these mushrooms is Beta-glucan, or Beta-D-glucan. The most studied mushroom Beta-glucans include Lentinan from Shiitake (Lenitus edodes), Grifolan and GRN from Maitake (Grifola frondosa), PSK (also called Krestin) and PSP from Kawartake (Coriolus versicolor), SSG from Sclerotinia sclerotiorum, and schizophyllan, also called SPG, from Schizophyllum commune. Other mushrooms and fungi studied in the medical literature include Hakumokuji (Tremella fuciformis), Tochukaso (Cordyceps sinensis), Choreimaitake (Polyporus umbellatus), and Reishi (Ganodema lucidum). Japanese mushrooms are among the most researched natural compounds used in cancer therapy.

What They Do . . .

Beta-glucans from Japanese mushrooms might have a cancer-preventive effect upon sarcomas, colon cancer, breast cancer, gastric cancer, adenocarcinomas, cervical cancer, and some leukemias. Beta-glucans also may interact with cancer treatments to increase their effects. Lentinan might enhance the effect of cisplatin. SPG may boost the treatment effects of radiation and surgery. Ganoderma may enhance the effect of antiplatelet drugs. Studies combining chemotherapy with Beta-glucans such as PSK showed that patients lived longer with the combination therapy. Cordyceps and Ganoderma protected the kidneys and liver from chemotherapy toxicity in some animal studies. Because of this encouraging research, Lentinan and SPG are now used as cancer treatment drugs in Japan.

Beta-glucans may have anticancer effects because of their immune-stimulating properties and their ability to inhibit immune suppression. PSK also works as an antioxidant through its ability to stimulate Superoxide Dismutase (SOD) production. SOD is one of the major antioxidant enzymes in the body.

What To Do . . .

The easiest way to get your Beta-glucans is to eat more mushrooms. Button mushrooms (Schizophyllum commune) and Shiitakes are available fresh, and many other mushrooms are available in dried form. Reconstitute the mushrooms by soaking in boiling water for 10 to 15 minutes, cut off the woody stems, and slice, and use like fresh in salads, soups, and casseroles. Using fresh or dried mushrooms is a good idea, but there's no proof that mushrooms will have the same protective, immune-enhancing effects as Beta-glucan supplements. Beta-glucans are available as supplement extracts in capsule and tincture form. A tincture is an herbal extract made with alcohol. Tinctures may be one of the best ways to extract and preserve nutrients in a stable soluble form. But they're full of alcohol. So the best way to use a tincture is to put whatever amount you're using in warm or hot water and let it sit 10 or 15 minutes. The alcohol will evaporate out. Some tinctures have a slight tinny taste but aren't unpleasant to drink.

What To Watch Out For . . .

There's not a lot of safety studies in Western medicine with Japanese mushrooms. Until more studies are done, young children, pregnant and nursing women, or those with severe kidney or liver disease should probably avoid taking these supplements. Side effects including nausea and other gastric discomforts have been reported. Reishi can thin the blood, and therefore isn't a good idea if you are taking blood-thinning medications such as coumadin (wayfarin) or heparin. These supplements are generally considered safe, but more safety data needs to be accumulated.

© Copyright 2002 Jill Place, MA, RD