Shiitake extract (lentinan)

Tier 3 — weak evidence · Immunity · Cancer adjunct · Cholesterol

Contains lentinan, a beta-glucan approved as an injectable cancer treatment in Japan. Oral shiitake extract modestly boosts immune markers and reduces cholesterol in small trials. The injectable form has stronger evidence than oral supplements. Regular shiitake consumption as food provides similar benefits. Very safe — one of the most commonly eaten mushrooms worldwide. Rare cases of shiitake dermatitis from raw consumption.

Dose: 5–10 g/day dried shiitake or 500–1,000 mg extract; eating the mushroom is as effective as supplements