# Shiitake (Lentinula edodes)

**Lentinula edodes**

**Known today as.** A brown mushroom of oak logs, cultivated in China and Japan for about a thousand years.

Kind: Fungus

## What was it used for?

Food and medicine in the East.

## What does modern science say?

Its polysaccharide lentinan has been used in Japan in cancer treatment. Eaten raw or undercooked it can cause a whip-like rash.

## Pharmacognosy and toxicology

- **lentinan**: a -glucan
- **eritadenine**: lowers cholesterol in animals
- **lenthionine**: the flavour

**Mechanism.** Lentinan, injected, stirs the immune system and is licensed in Japan beside chemotherapy for gastric cancer; eaten raw or undercooked, the mushroom causes a whip-like rash, shiitake dermatitis, in a few people.

**Dose.** Shiitake dermatitis from raw mushrooms, usually clearing in weeks.

**Standing.** A food; lentinan is a drug in Japan and China.

## What lore surrounds it?

Chinese tradition credits a Song dynasty woodsman with first learning to grow it on cut logs.

## Sources

- National Cancer Institute, PDQ: Medicinal Mushrooms.
- Nakamura, T. (1992). “Shiitake (*Lentinus edodes*) dermatitis.” *Contact Dermatitis* 27.
- Ina, K., et al. (2013). “The use of lentinan for treating gastric cancer.” *Anti-Cancer Agents in Medicinal Chemistry* 13.

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*Shiitake.* In *Materia Medica*, edited by B. C. P. Statema. Version 1, revised 2026-09-25. The Thinking Press. https://thethinkingpress.org/materia-medica/shiitake

Historical description, not medical advice.