Maitake Mushroom

otheroct-1-en-3-ol

What is it

Maitake (Grifola frondosa), also called hen of the woods, is a culinary and medicinal polypore mushroom native to East Asia, Europe, and North America. It is used as a food and as a source of beta-glucan polysaccharides, especially the D-fraction, for immune and metabolic support.

How it works

Maitake's principal bioactive is a complex of beta-glucans, with the D-fraction (a specific extract) being the most studied. These polysaccharides bind to receptors on macrophages, dendritic cells, and natural killer cells, modulating the production of cytokines including interferon-gamma and interleukins involved in immune surveillance. Research suggests maitake polysaccharides may influence glucose metabolism by enhancing insulin sensitivity. Some animal and small human studies show modest reductions in fasting glucose and improvements in HbA1c, though clinical evidence is preliminary. The SX-fraction has been specifically studied for metabolic effects. In oncology, maitake D-fraction has been investigated as an immune adjunct to chemotherapy, with reported effects on tumor markers and immune cell activity. Maitake is also a source of ergosterol, which can convert to vitamin D2 with UV exposure, and contains antioxidant phenolics.

Evidence for 4 uses

AI-assisted evidence assessment — talk to your doctor before relying on any single supplement.

Immune modulation

Grade C

Moderate evidence

Maitake D-fraction has shown immune-stimulating effects in clinical studies, with measurable changes in immune cell activity. Most evidence comes from small Japanese trials.

Blood glucose regulation

Grade D

Mixed evidence

Some animal and limited human studies suggest improvements in insulin sensitivity and modest reductions in fasting glucose. Clinical evidence is preliminary.

Cancer adjuvant

Grade D

Mixed evidence

Small studies of maitake D-fraction in cancer patients suggest improvements in immune parameters and possibly tumor response, but rigorous large trials are lacking. Not a substitute for standard cancer care.

Cholesterol management

Grade F

Limited evidence

Animal studies suggest cholesterol-lowering effects but human evidence is essentially absent.

4 commercial forms

Maitake D-fraction

Standardized polysaccharide extract; the most studied form for immune effects.

Patented liquid extract or capsule form with specific polysaccharide profile used in most clinical research.

Whole mushroom powder

Provides full bioactive profile at lower concentration.

Closest to consuming the mushroom; convenient for daily use.

SX-fraction

Specific extract studied for metabolic effects.

Subfraction marketed for blood sugar support. Less clinical evidence than D-fraction.

Hot water extract

Concentrates polysaccharides; standard extraction method.

Common form in capsules and tinctures.

Dosage

Typical doses are 1-3 grams per day of maitake powder or 0.5-2 grams of standardized extract. For D-fraction extracts, 30-100 mg per day has been used in clinical research. There is no established RDA.

When and how to take it

Maitake can be taken at any time of day, with or without food. For glucose management, some practitioners suggest taking it with meals. Consistent daily use over weeks is needed to evaluate effects on immune function or metabolic markers.

Food sources

Food	Amount	%DV
Fresh maitake mushroom (1 cup)	approx 70 grams; provides beta-glucans, vitamin D2 (if UV-exposed), and minerals	—
Dried maitake (1 oz)	approx 28 grams dried	—

Safety

Maitake is generally well tolerated. Side effects are uncommon and may include mild gastrointestinal upset, headache, or, rarely, allergic reactions. Long-term safety data are limited but available evidence suggests good tolerability.

Who should be cautious

People taking diabetes medications should monitor blood glucose closely when starting maitake. Avoid in pregnancy and breastfeeding due to insufficient safety data. People taking blood thinners, antihypertensives, or immunosuppressants should consult a clinician. Discontinue 1-2 weeks before scheduled surgery.

Interactions

Maitake may lower blood glucose and could enhance the effects of diabetes medications, requiring glucose monitoring. It may have mild antiplatelet effects and could theoretically increase bleeding risk with anticoagulants. Limited evidence suggests possible interaction with antihypertensive medications. Immune-modulating effects warrant caution with immunosuppressants.

Frequently asked questions

What is maitake D-fraction?⌄

D-fraction is a specific patented beta-glucan extract from maitake mushroom that has been the focus of most immune-related clinical research.

Can maitake help with blood sugar?⌄

Some studies suggest maitake may improve insulin sensitivity and modestly lower blood glucose, but evidence is preliminary. Diabetics taking medication should monitor glucose closely.

Is maitake edible?⌄

Yes, maitake is a popular edible mushroom with a savory flavor and meaty texture. Cooking is recommended for digestibility and flavor.

How long until I see immune effects?⌄

Most clinical trials use 4-12 weeks of consistent daily supplementation before measuring immune outcomes.

Are mushroom supplements as effective as eating the mushroom?⌄

Concentrated extracts deliver higher doses of polysaccharides than typical culinary servings. Both forms have value; extracts are typically used for therapeutic applications.

References

Wikidata: Maitake — Wikidata link

Track Maitake Mushroom with Pilora

Set up dose reminders, check interactions, and join the community in the Pilora iPhone app.

Coming to App Store

Disclaimer: These statements have not been evaluated by the FDA. This page is educational, not a substitute for personalized medical advice. Evidence grades are AI-assisted assessments — talk to your doctor before starting any new supplement, especially if you're pregnant, breastfeeding, on medications, or managing a chronic condition.