Herb library · Mushroom · Grifola frondosa
Maitake
An edible mushroom sold as an extract for immunity and alongside cancer care. Small trials in people show it changes immune measurements, in both directions, but have not shown clear health benefits.
Traditional use
An edible mushroom that NCI lists among the more common of the more than 100 mushrooms used in Asia alongside cancer care. People with cancer commonly take mushroom supplements hoping to support immune function, which is why its polysaccharide extract was tested in a US trial.
What studies show
- Limited
Immune function in breast cancer survivors: a phase I/II trial of 34 women found maitake extract changed immune measurements, raising some and lowering others, with no simple dose pattern. The researchers warned that it may depress as well as enhance immune function.
- Limited
Colds: in a 2026 placebo-controlled trial, bread with one maitake strain did not change how many colds people caught, but was linked to fewer days of fever and runny nose; the other strain showed little effect.
Be careful of
Cautions
- NoteIn the breast cancer trial, no dose-limiting side effects occurred; two women stopped early, one for nausea and joint swelling and one for rash and itching.
- ConditionIf you are having cancer care, tell your oncologist before taking maitake: its effects on the immune system can go in either direction.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
Sources
- Medicinal Mushrooms (PDQ®)–Patient Version (opens in a new tab) · NIH · read September 25, 2026
- A phase I/II trial of a polysaccharide extract from Grifola frondosa (Maitake mushroom) in breast cancer patients (2009) (opens in a new tab) · NIH · read September 25, 2026
- Maitake mushroom supplementation modulates upper respiratory symptoms and immune responses in healthy adults (2026) (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.