Background

• Shiitake mushrooms were originally cultivated on natural oak logs and only grown in Japan but are now available in the United States. These mushrooms are large, black-brown, and have an earthy rich flavor. This fungus is consumed in foods such as stir-fries, soups, and as a meat substitute.
• Shiitake contains proteins, fats, carbohydrates, soluble fiber, vitamins (A, B, B12, C, D, niacin), and minerals. Commercial preparations often use the powdered mycelium of the mushroom before the cap and stem grow. This preparation is called Lentinus edodes mycelium extract (LEM). LEM is rich in polysaccharides and lignans.
• Shiitake has been taken by mouth for boosting the immune system, decreasing cholesterol levels, and for anti-aging. Lentinan, derived from shiitake (Lentinus edodes), has been injected as an adjunct treatment for cancer and HIV infection, although currently high quality human scientific evidence is lacking for many proposed indications. Purified lentinan is considered a drug in Japan.

References

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