Quick Summary
Maitake (Grifola frondosa) is an edible and medicinal mushroom traditionally used in Asian countries for its potential immunomodulatory, anticancer, antioxidant, and metabolic health benefits. It contains bioactive polysaccharides such as β-glucans, among other compounds. While preclinical studies and some clinical evidence suggest potential benefits for cancer support, diabetes management, and immune function modulation, robust clinical data remain limited. Maitake is generally well-tolerated but requires further high-quality clinical trials to establish its efficacy and safety profiles.
What is it?
Maitake, also known as “hen of the woods,” is a mushroom native to northeastern Japan but widely cultivated and used worldwide. It grows at the base of oak trees and features multiple grayish-brown caps clustered together. Maitake has a history of use as both food and herbal medicine, prized for its complex polysaccharides and nutrients.
Traditional Uses
- Immune system support and modulation
- Complementary therapy in cancer care
- Managing blood sugar and metabolic health
- Antioxidant and anti-inflammatory applications
- Improving general well-being and vitality
Active Compounds
Maitake contains several bioactive constituents, primarily polysaccharides such as β-glucans, which are believed to modulate immune responses. Other compounds include various antioxidants and secondary metabolites that may contribute to its effects.
Potential Benefits with Evidence Levels
- Immunomodulation and Anticancer Support – Limited clinical evidence
Maitake polysaccharides have been reported to modulate immune parameters and show potential anticancer benefits, particularly as supportive care in cancer patients. Phase I/II trials in breast cancer patients showed immunological effects with complex dose-response patterns. Evidence mainly comes from in vitro, animal studies, and small human trials; larger randomized controlled trials (RCTs) are needed. - Metabolic Health – Diabetes and Obesity – Preclinical and early clinical evidence
Animal studies suggest maitake may improve glucose metabolism, insulin resistance, and lipid profiles, possibly by modulating gut microbiota and inflammation. Some medicinal plant systematic reviews include maitake for diabetes management, but conclusive clinical evidence is lacking. - Gut Microbiota Modulation and Prebiotic Effects – Preclinical evidence
In vitro and animal research indicate maitake polysaccharides resist digestion and beneficially alter gut microbiota composition, increasing favorable bacteria and promoting metabolites such as GABA. - Supportive Care in Oncology Treatment – Limited clinical evidence
When used adjunctively with chemotherapy or radiotherapy, maitake-containing mushroom extracts may reduce side effects and improve immune status. However, clinical trials report non-significant reductions in postoperative complications and mixed findings for adverse event reduction.
Side Effects
Maitake mushroom extracts are generally considered safe, with mild side effects reported infrequently. These include:
- Mild gastrointestinal symptoms such as nausea
- Joint swelling
- Rash and pruritus (itching)
- Potential immune suppression at certain doses
Phase I/II trials in breast cancer patients did not show dose-limiting toxicities, but immune responses may vary by dose. Further evaluation of long-term safety is recommended.
Drug Interactions
Specific clinical data on herb-drug interactions involving maitake are lacking. However, due to its immunomodulatory activity and polysaccharide content, possible interactions with immunosuppressants, anticoagulants, or chemotherapy drugs cannot be excluded. Caution and medical consultation are advised when combining maitake with conventional medications, especially during cancer treatment.
Who Should Avoid It
- Individuals with autoimmune diseases or those receiving immunosuppressive therapy should use caution because of maitake’s immune effects.
- Pregnant and breastfeeding women, due to insufficient safety evidence.
- People with known allergies to mushrooms or who have experienced adverse reactions to fungal products.
No well-established contraindications exist based on current clinical data, but further research is needed.
Evidence Limitations
- Most data come from preclinical in vitro and animal models; high-quality human clinical trials are limited.
- Clinical studies generally have small sample sizes, short durations, and variable dosing schemes.
- Immune effects appear dose-dependent and non-monotonic, complicating interpretation.
- Variability in mushroom extracts and preparations restricts direct comparison of studies.
- Data on long-term safety, pharmacokinetics, standardized doses, and drug interactions are lacking.
- Inadequate information on use during pregnancy, breastfeeding, and in vulnerable populations.
References
- Ulbricht C, et al. (2009). Maitake mushroom (Grifola frondosa): systematic review by the natural standard research collaboration. – Discusses potential in cancer, diabetes, and immune stimulation; highlights lack of systematic safety and efficacy studies and calls for RCTs.
- Deng G, et al. (2009). A phase I/II trial of a polysaccharide extract from Grifola frondosa in breast cancer patients: immunological effects. – Oral administration linked to measurable immunological effects with no dose-limiting toxicities; shows complex immune modulation.
- Kirdeeva Y, et al. (2026). The Inclusion of Dietary and Medicinal Mushrooms into Translational Oncology: Pros and Cons at the Molecular Level. – Reviews anticancer and immunomodulatory effects, suggesting supportive care benefits.
- Regueiro C, et al. (2025). The Effect of Fungal Nutraceutical Supplementation on Postoperative Complications… – Clinical trial showing non-significant postoperative complication reduction and significant gut microbiota changes.
- Wang Q, et al. (2025). In Vitro Gastrointestinal Digestion of Grifola frondosa Polysaccharides and Their Enhancement of GABA Production… – Demonstrates gut microbiota modulation and resistance to digestion.
- Jiang X, et al. (2021). Anti-Obesity Effect of Grifola frondosa through modulation of lipid metabolism via ceramide in mice fed a high-fat diet. – Shows improved metabolic parameters and inflammation control in mice.
- Rossi P, et al. (2018). β-Glucans from Grifola frondosa and Ganoderma lucidum in breast cancer: complementary and integrative medicine. – Reviews immunomodulatory and anticancer effects, emphasizing translational research needs.
- Gariboldi MB, et al. (2023). Anti-Cancer Potential of Edible/Medicinal Mushrooms in Breast Cancer. – Reviews antineoplastic activity and clinical data on edible mushrooms including maitake.
- Arunachalam K, et al. (2022). The Antioxidant Properties of Mushroom Polysaccharides can Potentially Mitigate Oxidative Stress and Insulin Resistance. – Systematic review of antioxidant and antidiabetic effects.
- Posadzki P, et al. (2013). Herb-drug interactions: an overview of systematic reviews. – Notes limited data on maitake but underlines need for caution due to possible interactions.
Last Reviewed
June 2024
Disclaimer: This page is for informational purposes only and does not provide medical advice, diagnosis, or treatment. Consult a qualified healthcare professional before using maitake or any herbal supplement, especially if you are pregnant, breastfeeding, have existing medical conditions, or are taking medications.