Herbal Monograph
Maitake
Grifola frondosa (Dicks.) Gray
Meripilaceae (Polyporales)
Prized edible and medicinal mushroom for immune modulation, blood sugar regulation, and metabolic health support
Overview
Plant Description
Maitake is a large, conspicuous polypore fungus that produces impressive, compound fruiting bodies (basidiocarps) at the base of living or dead hardwood trees. The fruiting body forms a dense, overlapping rosette of numerous spoon-shaped to fan-shaped individual caps (pilei) arising from a branched stipe structure, creating an appearance often compared to a sitting hen with ruffled feathers -- hence the common name 'Hen of the Woods.' Individual caps are 2-10 cm (1-4 inches) broad, thin, and somewhat leathery, with wavy or lobed margins. The upper surface is grayish-brown to dark brown, often with zones of lighter and darker coloration, and a finely fibrillose to smooth texture. The undersurface bears a white to cream-colored pore layer (hymenium) with very fine pores, approximately 1-3 pores per millimeter, with tubes rarely deeper than 3 mm. The branching stipe system is white to pale gray, tough, and fleshy when fresh. The entire fruiting body cluster can reach impressive dimensions of 20-60 cm (8-24 inches) across, and exceptionally large specimens up to 150 cm (60 inches) and weighing over 45 kg (100 lbs) have been documented. The flesh is white, firm, and has a pleasant earthy-mushroom aroma when fresh. Unlike the extremely woody texture of Reishi (Ganoderma lucidum), maitake is a prized edible mushroom with a rich, savory umami flavor, making it one of the few medicinal mushrooms that is also a choice culinary species. The fruiting body grows from an underground tuber-like structure called a sclerotium, roughly the size of a potato, which can persist in the soil for years and produce fruiting bodies annually. The species epithet 'frondosa' means 'having fronds' or 'leafy,' referring to the frond-like overlapping caps.
Habitat
In the wild, Grifola frondosa grows as a saprotroph and opportunistic weak parasite, primarily at the base of living or dead hardwood trees, with a strong preference for old-growth oaks (Quercus spp.). It also occurs on other hardwood species including maple (Acer spp.), elm (Ulmus spp.), beech (Fagus spp.), chestnut (Castanea spp.), hornbeam (Carpinus spp.), black walnut (Juglans nigra), sweetgum (Liquidambar styraciflua), and occasionally on conifers (Pinus, Pseudotsuga, Larix). The fungus causes a white butt rot of the heartwood and roots. Fruiting bodies typically appear in late summer through autumn (September through November in the Northern Hemisphere), often recurring at the same tree base year after year from the perennial subterranean sclerotium. Maitake favors warm, moist temperate forests with well-drained soil and moderate humidity.
Distribution
Grifola frondosa is native to temperate hardwood forests of the Northern Hemisphere. Its primary natural range includes northeastern Japan, China, and Korea in East Asia; central and northern Europe (particularly common in the United Kingdom, France, Germany, Italy, and Scandinavia); and eastern North America (from Nova Scotia and Quebec south to the Gulf states, and west to the Great Plains). The species is most abundant in the oak-dominated forests of northeastern North America and the deciduous forests of Japan. It is less common in western North America and absent from tropical regions. Japan has the longest continuous tradition of culinary and medicinal use, and the Japanese name 'maitake' has become the standard commercial name worldwide. Wild specimens are highly prized by foragers and can command premium prices, though commercial cultivation has made the mushroom widely available.
Parts Used
Fruiting body (whole basidiocarp)
Preferred: Dried sliced fruiting body for decoction or culinary use; hot-water extract powder; D-fraction or MD-fraction liquid extract; standardized extract capsules
The dried or fresh fruiting body is both the culinary and primary medicinal part. It contains the full spectrum of bioactive polysaccharides (beta-glucans including D-fraction precursors), proteins, ergosterol, amino acids, vitamins, and minerals. The fruiting body is the source material for the extraction of D-fraction and MD-fraction concentrates. Unlike many medicinal mushrooms (such as Reishi), maitake fruiting bodies are tender enough for culinary consumption, making it possible to obtain medicinal benefits through regular dietary inclusion. The fruiting body is used in TCM (as Hui Shu Hua), Japanese folk medicine, and modern supplement preparations.
D-fraction (purified beta-glucan extract)
Preferred: Standardized liquid extract (drops) or encapsulated extract; typically standardized to D-fraction or MD-fraction content
The D-fraction is the most extensively studied medicinal preparation of maitake. It is a purified, protein-bound beta-glucan extract isolated from the fruiting body through a proprietary process involving hot-water extraction, ethanol precipitation, and chromatographic separation. The D-fraction contains beta-1,6-glucan with beta-1,3-branched chains and has a molecular weight of approximately 1,000,000 Da. It was first isolated and characterized by Dr. Hiroaki Nanba at Kobe Pharmaceutical University in the 1980s. The further-purified form (MD-fraction) was patented in the 1990s and is the most commonly available standardized form in the supplement market. D-fraction has been the subject of the majority of immunological and cancer-related research.
SX-fraction (glycoprotein extract)
Preferred: Standardized SX-fraction capsules or tablets
A water-soluble glycoprotein fraction isolated from maitake with an approximate molecular weight of 20,000 Da. The SX-fraction is distinct from D-fraction in both molecular weight and composition, containing a protein-bound polysaccharide with specific activity on glucose metabolism. Research by Konno and colleagues demonstrated hypoglycemic and insulin-sensitizing effects in both animal models and preliminary human studies. The SX-fraction targets the insulin receptor (IR) and insulin receptor substrate 1 (IRS-1) signaling pathways, enhancing peripheral glucose uptake and insulin sensitivity.
Mycelium (cultured mycelial biomass)
Preferred: Dried mycelial powder or extract; capsules
Mycelium produced by submerged liquid fermentation or solid-state fermentation on grain substrates. Contains polysaccharides including beta-glucans and exopolysaccharides, though the beta-glucan profile may differ from the fruiting body. Products grown on grain substrates (mycelium-on-grain) may contain substantial residual starch that can inflate apparent polysaccharide content in non-specific assays. Quality and bioactive compound concentrations vary by production method.
Key Constituents
Polysaccharides (beta-glucans and protein-bound polysaccharides)
Polysaccharides are the primary bioactive constituents of maitake and the most extensively researched. The beta-glucan fractions (D-fraction, MD-fraction, grifolan) mediate the immunomodulating and antitumor activities through activation of innate immune pattern recognition receptors (Dectin-1, CR3, TLR-2/4) on macrophages, dendritic cells, and natural killer cells. The SX-fraction glycoprotein mediates the hypoglycemic and insulin-sensitizing activity through the insulin receptor signaling pathway. The distinction between different named fractions (D-fraction, MD-fraction, SX-fraction, grifolan) reflects different extraction, purification, and characterization approaches rather than fundamentally different molecules in some cases. Hot-water extraction is the primary method for polysaccharide recovery, and the protein-bound nature of the most active fractions appears to be important for their biological activity. The structural diversity of maitake polysaccharides underlies the breadth of its therapeutic applications across immune, metabolic, and hepatic systems.
Sterols and lipids
The sterol and lipid fraction of maitake contributes to its anti-inflammatory, metabolic, and nutritional value. Ergosterol provides a natural source of provitamin D2, which is particularly relevant given widespread vitamin D insufficiency and the role of vitamin D in immune function and bone health. The PPARdelta agonist activity of the lipid-soluble fraction is a mechanism distinct from the polysaccharide-mediated immunomodulation and contributes to the hypolipidemic, glucose-regulating, and anti-inflammatory effects of whole maitake preparations. COX inhibitory activity of ergone and related sterols provides additional anti-inflammatory support.
Proteins, amino acids, and enzymes
The protein and amino acid content of maitake serves dual nutritional and pharmacological roles. Nutritionally, maitake is among the more protein-rich edible mushrooms, providing essential amino acids and significant glutamic acid content (contributing to the umami flavor that makes it an attractive culinary-medicinal mushroom). Pharmacologically, the protein components are integral to the bioactivity of the D-fraction and SX-fraction glycoprotein complexes, and the recently characterized ACE-inhibitory peptides and immunomodulatory proteins represent additional bioactive constituents beyond the polysaccharide fractions.
Vitamins and minerals
The vitamin and mineral content of maitake contributes to its value as a functional food and distinguishes it from purely medicinal mushrooms (such as Reishi) that are too bitter or woody for culinary use. The naturally high vitamin D2 content is clinically relevant given the global prevalence of vitamin D insufficiency and the established role of vitamin D in immune regulation, bone metabolism, and chronic disease prevention. The B-vitamin content supports energy metabolism and nervous system function. The mineral profile, particularly potassium, aligns with cardiovascular health benefits.
Phenolic compounds and other bioactives
Phenolic compounds contribute to the antioxidant activity of maitake, complementing the immune-mediated and metabolic effects of the polysaccharide fractions. The antioxidant activity supports hepatoprotective effects and may contribute to the anti-aging and chronic disease prevention benefits attributed to regular maitake consumption.
Herbal Actions
Modulates and balances immune function
The defining pharmacological action of maitake. D-fraction and MD-fraction beta-glucans activate innate immune cells via pattern recognition receptors, particularly Dectin-1 and complement receptor 3 (CR3), on macrophages, dendritic cells, and natural killer (NK) cells. This activation enhances phagocytosis, upregulates costimulatory molecules (CD80, CD86, CD83, MHC-II) on antigen-presenting cells, and stimulates production of pro-immune cytokines including IL-1, IL-2, IL-12, TNF-alpha, and IFN-gamma. NK cell cytotoxicity is significantly increased. Clinical studies by Kodama et al. (2002, 2003) demonstrated activation of NK cells and maintenance of immune competence in cancer patients. The Deng et al. (2009) phase I/II trial in breast cancer patients revealed complex immunomodulatory effects -- both stimulatory and inhibitory depending on dose -- highlighting that maitake modulates rather than simply stimulates the immune system. This bidirectional quality supports the adaptogenic classification and long-term use profile.
[1, 2, 4, 5, 6]Helps the body adapt to stress and restore homeostasis
Classified as an adaptogen in modern integrative practice based on multiple criteria: broad-spectrum normalizing effects across immune, metabolic, and hepatic systems; bidirectional immunomodulation (up-regulating deficient immune function while not over-stimulating already-active responses); blood glucose normalization in both hypoglycemic and hyperglycemic conditions; and traditional long-term tonic use spanning centuries in Japanese and Chinese medicine. The Deng et al. (2009) study provided direct evidence of bidirectional immune modulation, with intermediate doses having either stimulatory or inhibitory effects depending on the immune parameter measured. Maitake's classification as a qi tonic in TCM and its role as a longevity food in Japanese tradition align with the adaptogenic concept of supporting overall resilience and homeostasis.
[1, 6, 7]A distinguishing therapeutic action of maitake among medicinal mushrooms. The SX-fraction glycoprotein demonstrates significant blood glucose-lowering activity through enhancement of insulin receptor (IR) and insulin receptor substrate 1 (IRS-1) signaling, improving peripheral insulin sensitivity and GLUT4-mediated glucose uptake. Konno et al. (2001) reported that Type 2 diabetic patients showed significant reductions in fasting blood glucose with SX-fraction supplementation. Additionally, alpha-glucan fractions and other polysaccharides have demonstrated hypoglycemic effects in diabetic animal models (KK-Ay mice, streptozotocin-induced diabetic rats) through improved insulin resistance, increased hepatic glycogen synthesis, and reduced hepatic gluconeogenesis. The hypoglycemic action is considered primary because of consistent evidence across in vitro, animal, and preliminary clinical studies, and because it represents a clinically significant therapeutic application distinct from general immunomodulation.
[1, 7]Multiple preclinical studies demonstrate cholesterol-lowering and triglyceride-reducing effects of maitake. In spontaneously hypertensive rats, maitake feeding suppressed serum total cholesterol, triglycerides, and phospholipid levels by 0.3-0.8 fold compared to controls. Maitake fiber (chitin-glucan complex) reduced serum and hepatic cholesterol in cholesterol-fed rats. The lipid-soluble fraction activates PPARdelta, a nuclear receptor involved in fatty acid oxidation, which promotes hepatic lipid catabolism and reduces adipose tissue accumulation. In high-fat-diet-induced obese mice, G. frondosa extract reduced body weight gain, visceral fat accumulation, and hepatic triglyceride storage. The hypolipidemic effect complements the hypoglycemic action, supporting maitake's use for metabolic syndrome.
[1, 8]Protects the liver from damage
G. frondosa polysaccharides demonstrated hepatoprotective effects in multiple animal models of liver injury. In carbon tetrachloride-induced liver injury, maitake water extract dose-dependently decreased serum transaminases (ALT, AST) and reduced hepatic histopathological changes. Maitake polysaccharides protected against lipopolysaccharide/D-galactosamine-induced acute liver injury through the miR-122-Nrf2/ARE antioxidant signaling pathway. Additionally, maitake D-fraction extracts strongly suppressed hepatitis B virus antigen secretion and replication in isolated human liver cells by approximately 90% even at low doses. The hepatoprotective action involves antioxidant enzyme enhancement (SOD, catalase, GPx), anti-inflammatory cytokine modulation, and direct hepatocyte protective effects.
[1, 8]Maitake D-fraction and polysaccharides demonstrate antitumor activity primarily through immune-mediated mechanisms rather than direct cytotoxicity. Preclinical evidence includes: tumor growth inhibition in sarcoma 180, mammary carcinoma (MM-46), and colon cancer models; enhanced dendritic cell-mediated antitumor immunity; elimination of myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment; synergistic enhancement of antibody-dependent cellular cytotoxicity (ADCC) with trastuzumab; and reduction of immunosuppression induced by chemotherapy agents (mitomycin-C, doxorubicin). A 2021 meta-analysis of preclinical studies confirmed significant antitumor effects of G. frondosa polysaccharides. Clinical evidence remains preliminary: Kodama et al. (2002, 2003) showed NK cell activation and tumor marker reduction in small cancer patient groups, and Deng et al. (2009) demonstrated measurable immunological effects in breast cancer patients. Maitake is NOT a cancer treatment but rather an immune-supportive adjunct during conventional therapy.
[2, 4, 5, 6, 8]Lowers blood pressure
Mild blood pressure-lowering effect demonstrated in preclinical models. Maitake feeding reduced blood pressure in spontaneously hypertensive rats (SHR). Mechanisms include ACE-inhibitory peptides identified through peptidomics analysis of maitake protein digests, and vasodilatory effects. The antihypertensive and metabolic effects of whole maitake powder and its fractions have been demonstrated in both SHR and SHRSP (stroke-prone) rat strains. The SX-fraction also favorably influenced blood pressure in streptozotocin-induced diabetic rats. The hypotensive effect is classified as mild because it is modest at typical dietary or supplement doses and clinical evidence in humans is lacking.
[1]Prevents or slows oxidative damage to cells
Both aqueous and ethanolic extracts of maitake demonstrate antioxidant activity through DPPH radical scavenging, superoxide anion scavenging, and metal chelation. Polysaccharide fractions enhance endogenous antioxidant enzyme systems (superoxide dismutase, catalase, glutathione peroxidase) in hepatic and other tissues. Ergosterol and phenolic compound fractions contribute additional antioxidant capacity. The antioxidant activity underlies and supports the hepatoprotective effects and contributes to the overall cytoprotective profile. In the Caenorhabditis elegans aging model, G. frondosa extract reduced fat accumulation and improved health span through the DAF-16/FOXO and SKN-1/NRF2 oxidative stress signaling pathways.
[1, 8]Therapeutic Indications
Immune System
Immunomodulation and immune support (general)
Multiple in vitro, in vivo, and clinical studies demonstrate that maitake D-fraction and related beta-glucan preparations enhance immune function. Kodama et al. (2002) reported IL-2 enhancement and activation of immunologically competent cells (NK cells, macrophages, T cells) in cancer patients (n=8) receiving D-fraction. Kodama et al. (2003) showed that D-fraction maintained peripheral blood NK cell activity and hindered metastatic progress in lung and breast cancer patients (n=10). The Deng et al. (2009) phase I/II trial in 34 breast cancer patients demonstrated statistically significant immunological effects (p < 0.0005), with dose-dependent modulation of multiple immune parameters. The 2021 preclinical meta-analysis (Zhao et al.) confirmed significant antitumor effects of G. frondosa polysaccharides across multiple animal models.
[2, 4, 5, 6, 8]Adjunctive support during cancer treatment
Clinical evidence for maitake as a cancer adjunct is preliminary but promising. Kodama et al. (2002, 2003) conducted nonrandomized studies showing D-fraction activated NK cells, reduced tumor markers, and hindered metastatic progression in small groups of cancer patients. Deng et al. (2009) conducted a properly designed phase I/II dose-escalation trial in 34 postmenopausal breast cancer patients, establishing safety (no dose-limiting toxicity) and demonstrating measurable immunological effects. Preclinical evidence is stronger: D-fraction enhanced the therapeutic effect of trastuzumab via antibody-dependent cellular cytotoxicity in HER2-positive breast cancer models (2024), reduced doxorubicin toxicity while enhancing bone marrow colony formation, and eliminated tumor-promoting myeloid-derived suppressor cells. However, these remain preliminary or preclinical findings. Maitake is NOT validated as a cancer treatment and should only be used as an adjunct alongside conventional oncological care.
[4, 5, 6, 8]Recurrent infections and immunodeficiency
Traditional use as an immune-strengthening tonic to reduce susceptibility to recurrent infections. The potent activation of innate immune cells (macrophages, NK cells, dendritic cells) by maitake beta-glucans provides a strong pharmacological rationale for this indication. Enhancement of mucosal and systemic immune surveillance has been demonstrated in preclinical models. Clinical evidence specific to infection frequency reduction is limited, though immune parameter enhancement is well documented.
[1, 2]Endocrine System
Type 2 diabetes mellitus and insulin resistance
The SX-fraction glycoprotein demonstrates significant blood glucose-lowering and insulin-sensitizing effects. Konno et al. (2001) reported that seven Type 2 diabetic patients showed significant reductions in fasting blood glucose after 2-4 weeks of SX-fraction supplementation while maintaining their usual oral medications. The mechanism involves activation of the insulin receptor (IR) and insulin receptor substrate 1 (IRS-1) signaling cascade, enhancing GLUT4 translocation and peripheral glucose uptake. Additional polysaccharide fractions (alpha-glucans, F2 and F3 fractions) demonstrated hypoglycemic effects in multiple diabetic animal models (KK-Ay mice, streptozotocin-induced rats) through improvement of insulin resistance, increased hepatic glycogen synthesis, and modulation of gut microbiota. While human data are limited to small pilot studies, the consistency of evidence across multiple preparations and models earns a 'supported' rating.
[1, 7]Metabolic syndrome
Maitake addresses multiple components of metabolic syndrome simultaneously: hyperglycemia (SX-fraction and polysaccharide-mediated insulin sensitization), hyperlipidemia (PPARdelta activation, cholesterol and triglyceride reduction), hypertension (ACE-inhibitory peptides), and visceral adiposity (reduced fat accumulation in high-fat-diet models). In high-fat-diet-induced obese mice, G. frondosa extract significantly reduced body weight gain, visceral fat accumulation, hepatic triglyceride storage, and improved glucose tolerance over 15 weeks of supplementation. The multi-target metabolic activity makes maitake particularly suited for metabolic syndrome, though integrated clinical trials in human metabolic syndrome patients are still needed.
[1, 7]Weight management support
Preclinical evidence suggests maitake may support healthy weight management through multiple mechanisms: PPARdelta-mediated fatty acid oxidation, reduced visceral fat accumulation, improved leptin and adiponectin signaling, and enhanced insulin sensitivity which reduces lipogenic drive. In obese mouse models, maitake extract supplementation significantly reduced body weight gain independent of caloric restriction. The SX-fraction has been associated with modest weight reduction in preliminary human observations. Clinical evidence is very limited; this indication should be considered adjunctive to dietary and lifestyle modification.
[1, 7]Hepatobiliary System
Hepatoprotection and liver support (general)
G. frondosa polysaccharides and water extracts demonstrated hepatoprotective effects in multiple animal models. In carbon tetrachloride-induced liver injury, maitake water extract dose-dependently reduced serum ALT and AST levels and attenuated hepatic histopathological changes. Polysaccharides protected against LPS/D-galactosamine-induced acute liver injury via the miR-122-Nrf2/ARE antioxidant pathway. Maitake feeding reduced hepatic lipid accumulation in high-fat-diet models. D-fraction strongly suppressed hepatitis B virus antigen secretion and replication in isolated human liver cells by approximately 90%. Maitake's metabolic effects (lipid reduction, glucose normalization) indirectly support liver health by reducing the metabolic burden that contributes to non-alcoholic fatty liver disease.
[1, 8]Non-alcoholic fatty liver disease (NAFLD) support
The combination of hepatoprotective, hypolipidemic, and insulin-sensitizing effects makes maitake a promising adjunctive agent for NAFLD. In high-fat-diet animal models, maitake reduced hepatic triglyceride storage, decreased liver lipid accumulation, and improved hepatic insulin sensitivity. The PPARdelta agonist activity of the lipid-soluble fraction promotes hepatic fatty acid oxidation. No clinical trials specific to NAFLD have been conducted, but the preclinical rationale is strong.
[1]Cardiovascular System
Hypertension support (mild, as adjunctive therapy)
In spontaneously hypertensive rats (SHR), dietary maitake supplementation significantly reduced systolic blood pressure. The antihypertensive effect involves multiple mechanisms: ACE-inhibitory peptides identified in maitake protein digests, modulation of oxidative stress in vascular tissue, and indirect effects through improved insulin sensitivity (hyperinsulinemia contributes to hypertension). SX-fraction also favorably influenced blood pressure in diabetic rat models. No controlled clinical trials in hypertensive humans have been conducted. The blood pressure-lowering effect is modest and maitake should be considered an adjunctive rather than primary antihypertensive agent.
[1]Hyperlipidemia (elevated cholesterol and triglycerides)
Consistent preclinical evidence demonstrates cholesterol-lowering effects of maitake. In cholesterol-fed rats, maitake fiber significantly reduced serum total cholesterol compared to controls. Maitake feeding suppressed serum cholesterol, triglycerides, and phospholipid values by 30-80% relative to control animals. The lipid-soluble fraction activates PPARdelta, promoting fatty acid oxidation and reducing lipogenesis. In cholesterol-fed mice, maitake extract reduced plasma cholesterol and modulated hepatic gene expression related to lipid metabolism. Clinical evidence in humans is limited to observational reports.
[1]Digestive System
Digestive support and Spleen qi tonification
In traditional Chinese medicine, maitake (Hui Shu Hua) is classified as a Spleen qi tonic that strengthens digestive function, improves appetite, and transforms dampness in the middle jiao. The polysaccharides act as prebiotics, supporting beneficial gut microbiota composition. As an edible mushroom with high dietary fiber (chitin-glucan complex), maitake supports healthy bowel function and provides substrate for colonic fermentation. Traditional Japanese folk medicine valued maitake as a restorative food for weak digestion and poor appetite.
[1]Musculoskeletal System
Bone health support (via vitamin D2)
Maitake is one of the richest natural food sources of vitamin D2, particularly when UV-treated. Adequate vitamin D status is essential for calcium absorption and bone mineralization. The combination of bioavailable vitamin D2, minerals (calcium, phosphorus, magnesium), and anti-inflammatory effects provides a rationale for maitake as a supportive food for bone health. No clinical trials have specifically evaluated maitake for bone density outcomes.
[1]Energetics
Temperature
neutral
Moisture
slightly dry
Taste
Tissue States
damp/stagnation, cold/depression, heat/excitation
In traditional Chinese medicine, Hui Shu Hua (maitake) is classified as sweet in taste and neutral to slightly cool in temperature, entering the Spleen, Stomach, and Liver channels. The sweet taste reflects its tonic quality -- strengthening the Spleen, tonifying qi, and supporting the center (zhong qi). As a Spleen qi tonic, maitake addresses patterns of Spleen deficiency with dampness: fatigue, poor appetite, loose stools, and metabolic sluggishness. The slight coolness distinguishes it from warming tonics like Astragalus and makes it suitable for constitutions with mild heat or damp-heat patterns. In Western herbal energetics, maitake is considered neutral to slightly cool in temperature and mildly drying in its moisture quality -- the latter reflecting its capacity to resolve metabolic dampness (hyperlipidemia, hyperglycemia, fluid retention). Maitake addresses damp/stagnant tissue states (metabolic syndrome, lipid and glucose dysregulation, hepatic congestion), cold/depressed states (immune deficiency, fatigue, depleted vitality), and to some degree heat/excitation states (inflammation, immune over-activation) through its bidirectional immunomodulation. The culinary palatability and mild energetic profile support long-term use across a wide range of constitutional types. CAVEAT: Herbal energetics are interpretive frameworks within Western herbalism and TCM, not standardized across all practitioners.
Traditional Uses
Japanese folk medicine and culinary tradition
- Highly prized edible mushroom consumed for both flavor and health benefits
- Named 'maitake' (dancing mushroom) because foragers would dance with joy upon finding it in the wild
- Valued at its weight in silver during the feudal era; traded as currency between daimyo (provincial nobles) and the shogun
- General health tonic consumed regularly for vitality, longevity, and disease resistance
- Supporting immune function and preventing seasonal illnesses
- Strengthening digestion and improving appetite
- Supporting liver function and overall metabolic health
- Used as a restorative food during convalescence from illness
"In Japan, maitake (舞茸, literally 'dancing mushroom') has been foraged from old-growth oak forests and consumed as both a choice edible and health-promoting mushroom for centuries. The name reportedly derives from the joy displayed by foragers upon discovering this prized fungus -- they would dance around with happiness. During the feudal era (1185-1868), maitake was so highly valued that it was used as currency; the daimyo (provincial lords) would trade maitake for its weight in silver with the shogun. Japanese folk medicine recognized maitake as a strengthening food suitable for the weak and convalescing, and as a general tonic for maintaining good health. The locations of productive maitake-producing trees were kept as closely guarded family secrets, passed down through generations."
Traditional Chinese medicine (TCM)
- Known as Hui Shu Hua (灰树花, 'gray tree flower') in TCM materia medica
- Tonifying the Spleen and Stomach qi; strengthening the center (zhong qi)
- Transforming dampness and resolving metabolic stagnation
- Supporting liver function and regulating intestinal health
- Balancing metabolism and restoring the body's vital energy (qi)
- Clearing damp-heat patterns and supporting urinary function
- General tonic for deficiency patterns with fatigue, poor appetite, and weakness
"In Chinese medicine, Grifola frondosa has been used since at least the Han Dynasty era (206 BCE - 220 CE), referenced in early materia medica texts as a medicinal fungus. Known as Hui Shu Hua, it is classified as a sweet, neutral herb that enters the Spleen, Stomach, and Liver channels. Its primary TCM actions are to strengthen the Spleen, supplement qi, and transform dampness. It is prescribed for patterns of Spleen qi deficiency with fatigue, poor appetite, and loose stools, and for damp accumulation manifesting as metabolic sluggishness. The Chinese pharmacological tradition recognizes both the dietary and medicinal value of maitake, consistent with the food-as-medicine principle central to TCM nutritional therapy."
[1]
North American and European folk use
- Foraged as a choice edible mushroom known as 'Hen of the Woods' in English-speaking countries
- Valued by foragers as one of the 'foolproof four' easily identifiable edible mushrooms (along with puffballs, morels, and chicken of the woods)
- Consumed as a nourishing food during autumn mushroom season
- Growing contemporary use as a functional food and dietary supplement for immune support
- Increasingly incorporated into integrative and naturopathic protocols for cancer support, metabolic health, and immune modulation
"In North America and Europe, Grifola frondosa has long been appreciated as a choice edible wild mushroom. Known as Hen of the Woods (and sometimes Ram's Head or Sheep's Head), it is eagerly sought by foragers in autumn, particularly in the oak-rich forests of the eastern United States. While lacking the millennia-long medicinal tradition of East Asian use, Western recognition of maitake's medicinal properties has grown rapidly since the 1980s following the pioneering research of Dr. Hiroaki Nanba on D-fraction beta-glucans. Today, maitake supplements (particularly D-fraction and MD-fraction products) are among the most popular medicinal mushroom products in the North American and European integrative medicine market."
Modern Research
D-fraction effect on NK cell activation in cancer patients
Nonrandomized clinical study evaluating the effect of Maitake D-Fraction on natural killer (NK) cell activity and immune parameters in patients with stage II-IV lung and breast cancers.
Findings: In cancer patients (n=10), maitake D-fraction hindered metastatic progression, reduced the expression of tumor markers, and increased NK cell activity in all patients examined. D-fraction appeared to repress cancer progression primarily through stimulation of NK cell activity. IL-2 levels were enhanced, indicating activation of immunologically competent cells including NK cells, macrophages, and T cells. The study provided early clinical evidence that maitake D-fraction could modulate immune function in cancer patients.
Limitations: Nonrandomized, uncontrolled study design. Very small sample size (n=10). Lack of blinding. No placebo control group. Heterogeneous patient population (both lung and breast cancer). Cannot establish causation. Results are considered preliminary and hypothesis-generating rather than definitive.
[5]
MD-fraction as cancer adjunct (nonrandomized clinical report)
Clinical report examining whether maitake MD-fraction could benefit cancer patients, assessing tumor regression, tumor marker changes, and quality of life outcomes across multiple cancer types.
Findings: Kodama et al. reported evidence of tumor regression or symptomatic improvement in cancer patients receiving MD-fraction alongside conventional treatment. The MD-fraction was associated with enhanced immune parameters and improved quality of life measures. Responses varied by cancer type, with breast, lung, and liver cancers showing some degree of response. The study suggested that MD-fraction may be most effective when combined with chemotherapy rather than used alone.
Limitations: Nonrandomized, uncontrolled clinical report. Significant methodological concerns have been raised by peer reviewers, including lack of adequate statistical analysis and potential reporting biases. The study has been criticized for apparent errors in data presentation. Results should be interpreted with caution and require confirmation in properly controlled trials.
[4]
Phase I/II trial of maitake polysaccharide extract in breast cancer patients
Properly designed phase I/II dose-escalation trial evaluating the safety and immunological effects of oral Grifola frondosa polysaccharide extract (maitake liquid extract) in 34 postmenopausal breast cancer patients who were free of disease after initial treatment. Five sequential cohorts received escalating doses (0.1, 0.5, 1.5, 3, or 5 mg/kg twice daily) for 3 weeks.
Findings: No dose-limiting toxicity was encountered, establishing safety across the dose range tested. There was a statistically significant association between maitake dose and immunologic function (p < 0.0005). Critically, the dose-response curves for many immune endpoints were non-monotonic: intermediate doses had either immune-enhancing or immune-suppressing effects compared to both high and low doses. The largest functional changes (>50% above baseline) were seen in granulocyte response to PMA stimulation, IL-10 production from CD14+ and CD3+ cells, IL-2 production from CD56+/CD3+ cells, and TNF-alpha production from CD3+ cells -- all peaking at intermediate doses of approximately 5-7 mg/kg per day. The study demonstrated that maitake produces complex, bidirectional immunomodulatory effects rather than simple unidirectional immune stimulation.
Limitations: Phase I/II design; not a randomized placebo-controlled efficacy trial. Small sample size per dose cohort. Disease-free breast cancer patients only; results may not generalize to active cancer or other conditions. Short intervention period (3 weeks). Immunological parameters are surrogate endpoints, not clinical outcomes. Single-center study. The non-monotonic dose-response pattern complicates dose optimization.
[6]
SX-fraction and Type 2 diabetes mellitus
Pilot clinical observation evaluating the hypoglycemic effects of maitake SX-fraction supplementation in patients with Type 2 diabetes mellitus, published as a letter in Diabetic Medicine.
Findings: Seven adults with Type 2 diabetes added SX-fraction to their existing oral medication regimen for 2-4 weeks. All seven patients showed sizable drops in fasting blood glucose during the trial period. The mechanism of action was attributed to SX-fraction's enhancement of insulin receptor (IR) and insulin receptor substrate 1 (IRS-1) signaling, leading to improved peripheral glucose uptake. In associated animal studies, SX-fraction significantly reduced blood glucose levels in streptozotocin-induced diabetic mice and improved insulin sensitivity markers.
Limitations: Very small sample size (n=7). Open-label, uncontrolled observation without placebo group. Short duration (2-4 weeks). Published as a letter rather than a full research article. Patients continued concurrent oral medications, confounding attribution. Requires confirmation in adequately powered, randomized, placebo-controlled trials.
[7]
Maitake D-fraction: healing and preventive potential for cancer
Foundational paper by Hiroaki Nanba describing the isolation, characterization, and antitumor activity of maitake D-fraction, published in the Journal of Orthomolecular Medicine. This paper established the scientific basis for D-fraction research and introduced the concept of maitake as a potent immunomodulating medicinal mushroom.
Findings: Nanba systematically screened six polysaccharide fractions (A-F) from G. frondosa fruiting body and identified the D-fraction (beta-1,6-glucan with beta-1,3-branches, protein-bound, MW approximately 1,000,000 Da) as having the highest antitumor activity. D-fraction increased NK cell, cytotoxic T-cell, and delayed-type hypersensitivity T-cell activity by 1.5-2.2 fold. In animal tumor models (sarcoma 180), D-fraction produced significant tumor regression. The mechanism was identified as immune-mediated rather than directly cytotoxic. Nanba also described the development of the more purified MD-fraction and its potential for clinical application.
Limitations: Primarily preclinical (animal model) data. The review format includes both original research results and interpretive conclusions. Commercial interest (Nanba patented the MD-fraction extraction process). Animal model results require clinical validation. Some of the claimed clinical benefits have not been independently confirmed in rigorous trials.
[2]
Systematic review of maitake mushroom (Natural Standard Research Collaboration)
Comprehensive systematic review of Grifola frondosa conducted by the Natural Standard Research Collaboration, evaluating the scientific evidence for safety, efficacy, pharmacology, interactions, and dosing. Electronic searches were conducted across 10 databases and 20 additional journals.
Findings: The review identified three indications with the most supporting evidence: cancer (adjunctive), diabetes, and immunostimulation. Based on popular use and available scientific data, maitake showed promise for these applications. Pharmacological evidence supported immunomodulatory effects (beta-glucan-mediated NK cell and macrophage activation), hypoglycemic effects (SX-fraction insulin sensitization), and lipid-lowering effects. Safety profile was favorable, with maitake well tolerated in available studies. The review noted that maitake has a long history of culinary use supporting its basic safety.
Limitations: Concluded that there was a lack of rigorous systematic study on safety and effectiveness in humans. Much of the evidence base relied on preclinical studies, small uncontrolled clinical observations, and traditional use reports. Called for future randomized controlled trials to validate the promising preclinical and preliminary clinical findings.
[1]
Antitumor activities of Grifola frondosa polysaccharide: preclinical meta-analysis
Systematic meta-analysis of preclinical (in vivo) studies evaluating the antitumor efficacy and mechanisms of Grifola frondosa polysaccharides. Searched PubMed/MEDLINE, EMBASE, Web of Science, and Chinese databases through December 2020.
Findings: The meta-analysis confirmed significant antitumor effects of G. frondosa polysaccharides across multiple animal tumor models. Polysaccharides exerted antitumor activity primarily through immune system activation: enhancing NK cell cytotoxicity, promoting dendritic cell maturation and antigen presentation, stimulating T-cell proliferation and cytokine production, and eliminating immunosuppressive myeloid-derived suppressor cells in the tumor microenvironment. The analysis provided systematic evidence supporting the immunological mechanism of maitake's antitumor effects.
Limitations: Meta-analysis of preclinical (animal) studies; results do not directly translate to human clinical efficacy. Heterogeneity in polysaccharide preparations, dosing, tumor models, and outcome measures across included studies. Publication bias possible. Quality of included studies was variable. The gap between preclinical evidence and clinical validation remains substantial.
[8]
Maitake extract reduces fat accumulation and improves health span in C. elegans
Study investigating the anti-aging and metabolic effects of Grifola frondosa extract using the C. elegans model organism, with focus on fat metabolism and longevity signaling pathways.
Findings: G. frondosa extract reduced fat accumulation and improved health span in C. elegans through activation of the DAF-16/FOXO and SKN-1/NRF2 signaling pathways. These pathways are conserved master regulators of longevity, stress resistance, and oxidative defense across species. The findings suggest that maitake's metabolic and anti-aging benefits involve fundamental cellular signaling mechanisms beyond specific immune modulation, providing molecular support for the traditional association between maitake consumption and longevity.
Limitations: C. elegans model; relevance to human physiology requires extrapolation. Specific extract composition and dosing in the worm model may not reflect typical human consumption. Longevity pathway activation does not directly prove anti-aging effects in humans.
[8]
Maitake beta-glucan enhances trastuzumab efficacy in HER2-positive breast cancer
Preclinical study (2024) investigating whether maitake beta-glucan could enhance the therapeutic efficacy of trastuzumab (Herceptin) in HER2-positive breast cancer through antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC).
Findings: Maitake beta-glucan significantly enhanced the anti-tumor activity of trastuzumab through both ADCC and CDC pathways. The combination of maitake beta-glucan with trastuzumab produced greater tumor cell killing than either agent alone. The beta-glucan appeared to prime immune effector cells (NK cells, macrophages) via complement receptor 3 (CR3) binding, enhancing their capacity for antibody-mediated tumor cell destruction. These findings suggest potential for maitake beta-glucan as an adjunct to monoclonal antibody cancer therapies.
Limitations: In vitro study; clinical relevance requires human trials. Specific beta-glucan preparation may not reflect commercially available supplements. The synergistic interaction observed in cell culture may not translate directly to the complex tumor microenvironment in vivo.
[8]
Preparations & Dosage
Standardized Extract
Strength: D-fraction liquid: typically 1 mg D-fraction per 5-6 drops. MD-fraction capsules: 3-25 mg per capsule with 75-250 mg whole maitake powder. Standardization to specific beta-glucan content varies by manufacturer.
D-fraction or MD-fraction liquid extract is the most extensively studied medicinal preparation of maitake. Commercially prepared by hot-water extraction of dried fruiting body followed by ethanol precipitation and chromatographic purification of the beta-glucan fraction. Products are standardized to D-fraction or MD-fraction content. Grifron Pro D-Fraction is the branded form of Nanba's patented extraction. Available as liquid drops or encapsulated extract.
D-fraction liquid: 0.5-1.0 mg per kg body weight per day, typically 35-70 mg daily for a 70 kg adult. Commercial products typically provide 3-25 mg MD-fraction per capsule. Manufacturer recommendations for disease prevention: 12-25 mg extract daily plus up to 2,500 mg whole maitake powder. For therapeutic support (cancer adjunct, diabetes): higher doses of 100-150 mg MD-fraction daily plus 4-6 g whole powder have been used in clinical observations.
Two to three times daily, taken between meals for optimal absorption of D-fraction liquid extract. Capsules may be taken with or without food.
May be used long-term. Clinical studies have used 3-12 week protocols. Traditional culinary use supports extended daily consumption. For cancer adjunctive use: continue throughout treatment course under practitioner guidance.
Not well-established for children. Maitake as a culinary food is appropriate for children. Concentrated D-fraction extracts: consult a qualified practitioner.
D-fraction and MD-fraction standardized extracts are the forms with the most clinical and preclinical research support. The liquid drop form allows flexible dosing based on body weight. For immune support and cancer adjunctive use, D-fraction/MD-fraction extracts are preferred over crude powder due to the concentrated and standardized beta-glucan content. Product quality varies significantly; look for products that specify the D-fraction or MD-fraction content per serving and are third-party tested for beta-glucan content (not just total polysaccharides, which may include non-bioactive starch).
Capsule / Powder
Strength: Crude powder: 500 mg per capsule. Extract powder: varies by manufacturer, typically 4:1 to 10:1 concentration ratio. SX-fraction: standardized glycoprotein content per capsule.
Dried fruiting body, finely powdered, filled into vegetarian or gelatin capsules. Alternatively, hot-water extract powder (concentrated) encapsulated. For SX-fraction products: standardized glycoprotein extract in capsule form. Available as crude powder capsules (500 mg) or concentrated extract capsules.
Crude fruiting body powder: 1-6 g daily (2-12 capsules of 500 mg) in divided doses. Extract powder (concentrated): 0.5-2 g daily depending on concentration ratio. SX-fraction capsules: follow manufacturer standardization guidelines, typically 72-144 mg standardized extract daily.
Two to three times daily with water, may be taken with or between meals
May be used long-term as a daily supplement
Not well-established for concentrated extract capsules. Whole mushroom powder at culinary doses is appropriate for children.
Capsules of whole dried fruiting body powder provide all maitake constituents but at lower concentration than D-fraction extracts. Bioavailability of unextracted powder may be limited by the chitin cell wall matrix; hot-water or dual-extracted powders are preferred for therapeutic use. Products should specify whether they contain crude powder or extract, the part used (fruiting body vs. mycelium-on-grain), and the beta-glucan content. Mycelium-on-grain products may contain significant residual starch that inflates apparent polysaccharide content in non-specific assays.
[1]
Decoction
Strength: 3-10 g dried fruiting body per 500-750 mL water; decoction ratio approximately 1:50-1:75
Use dried, sliced fruiting body pieces. Add 3-10 g of dried maitake to 500-750 mL of cold water. Bring to a boil, then reduce to a gentle simmer for 20-40 minutes. Strain and drink. Unlike the extremely woody Reishi, maitake is softer and requires less extensive decoction time. The resulting liquid has a pleasant, earthy-mushroom flavor that is much milder and more palatable than Reishi decoction. A second decoction from the same material can be prepared by adding fresh water and simmering for an additional 20-30 minutes.
3-10 g dried fruiting body per day, decocted in 2-3 cups of water. Drink throughout the day in 2-3 divided doses.
1-2 times daily (decoction prepared once and divided into portions)
May be used long-term as a daily tonic beverage. Traditional use supports extended daily consumption.
Suitable for children as a food-medicine tea at half adult dose. Maitake decoction is mild and well-tolerated.
Decoction is a traditional preparation method that efficiently extracts water-soluble polysaccharides (beta-glucans and glycoproteins). Unlike Reishi, which requires prolonged decoction (1-2 hours) due to its extremely woody texture, maitake's softer fruiting body releases its water-soluble constituents more readily. The pleasant umami flavor of maitake decoction makes it considerably more palatable than bitter Reishi tea, supporting compliance with long-term use. Adding maitake to soups and broths serves dual culinary and medicinal purposes. Note that decoction alone does not extract lipid-soluble constituents (ergosterol, PPARdelta agonists); for these, an ethanolic or dual extraction is needed.
[1]
Tincture
Strength: 1:5, 40-60% ethanol (dried fruiting body). Dual-extraction tinctures combine hydroalcoholic and aqueous extracts.
Use dried, finely chopped or powdered fruiting body. Standard maceration: 1:5 ratio in 40-60% ethanol. Macerate for 4-6 weeks with daily agitation. Press and filter. For a dual-extraction tincture: prepare a standard ethanol tincture AND a separate hot-water decoction (simmered 30-60 minutes), then combine the strained liquids in equal proportions. The dual extraction captures both polysaccharides (water-soluble) and lipid-soluble sterols and PPARdelta-active compounds.
2-5 mL (40-100 drops) two to three times daily
Two to three times daily
May be used long-term. Reassess periodically.
Not recommended for young children due to alcohol content. Glycerite preparations may be substituted.
Tincture preparation captures the lipid-soluble constituents (ergosterol, ergone, PPARdelta-active compounds) that are not efficiently extracted by water alone. A dual-extraction tincture (combining separate ethanol and water extractions) provides the most complete chemical profile. Maitake requires lower alcohol concentration (40-60%) than Reishi (60-75%) due to its less dense, less woody tissue. The tincture has a milder, more pleasant flavor than Reishi tincture due to the absence of intensely bitter ganoderic acid triterpenoids.
[1]
culinary
Strength: Fresh fruiting body; approximately 10:1 fresh-to-dried weight ratio
Fresh or dried maitake fruiting body used in culinary preparations. Fresh maitake can be sauteed, grilled, roasted, or added to soups, stir-fries, risottos, and pasta dishes. Tear into bite-sized pieces along the natural growth lines rather than cutting with a knife for best texture. Saute in butter or oil over medium-high heat until edges are golden and crispy (7-10 minutes). Dried maitake should be rehydrated in warm water for 20-30 minutes before cooking; the soaking liquid retains water-soluble polysaccharides and should be used as broth.
No established therapeutic dose for culinary consumption. Regular dietary inclusion of 50-150 g fresh maitake (equivalent to 5-15 g dried) several times per week provides meaningful polysaccharide, vitamin D2, and mineral intake.
As desired; several times per week for health maintenance
Ongoing as part of a varied diet
Suitable for children as a food. Introduce gradually as with any new food.
Maitake is one of the few medicinal mushrooms that is also a highly prized culinary species. Its rich, earthy umami flavor and tender, meaty texture make it one of the most sought-after wild mushrooms. Regular culinary consumption provides a meaningful intake of beta-glucan polysaccharides, vitamin D2 (especially if UV-exposed), B-vitamins, minerals, and dietary fiber. Cooking does not destroy the beta-glucan polysaccharides; in fact, heat and water exposure may improve their extractability and bioavailability. The culinary route is the most traditional and accessible way to obtain maitake's health benefits and supports long-term compliance. Fresh maitake is increasingly available at farmers markets, specialty grocery stores, and Asian markets.
powder
Strength: Crude dried fruiting body powder; 1:1 (no concentration). Some products use hot-water extracted then spray-dried powder at 4:1 to 10:1 concentration.
Dried fruiting body ground to a fine powder (40-80 mesh). Can be added to smoothies, soups, broths, coffee, tea, or encapsulated. For medicinal use, dissolve 1-2 teaspoons in hot water or broth to prepare a quick infusion. Store in an airtight container away from light, heat, and moisture.
1-6 g (approximately 1/2 to 2 teaspoons) daily in divided doses. For maintenance/preventive use: 1-3 g daily. For therapeutic support: 3-6 g daily.
One to three times daily, mixed into food or beverages
May be used long-term
Half adult dose for children over 6 under practitioner guidance.
Powdered whole fruiting body is a versatile and economical preparation. When dissolved in hot water or added to soups, it approximates a quick decoction. The fine grinding partially disrupts the chitin cell wall matrix, improving bioavailability compared to larger dried pieces. However, crude powder still contains the intact cell wall matrix and delivers lower concentrations of specific bioactive fractions (D-fraction, SX-fraction) compared to standardized extracts. For general health maintenance and nutritional supplementation, powder is an excellent choice. For specific therapeutic applications (cancer adjunct, diabetes management), standardized D-fraction or SX-fraction preparations are preferred.
[1]
Safety & Interactions
Class 1
Can be safely consumed when used appropriately (AHPA Botanical Safety Handbook)
Contraindications
Although rare, allergic reactions to maitake are possible, particularly in individuals with known fungal allergies. Some individuals have reported allergic reactions including skin rash, pruritus, and gastrointestinal symptoms. Cross-reactivity with other mushroom species in the Polyporales order is theoretically possible. Individuals with confirmed allergy to G. frondosa should not use maitake products.
Maitake's potent immunomodulating (immune-enhancing) properties, particularly the D-fraction-mediated activation of NK cells, T cells, and macrophages, could theoretically oppose the immunosuppressive effects of transplant anti-rejection medications (cyclosporine, tacrolimus, sirolimus). This could increase the risk of graft rejection. Transplant recipients should NOT use maitake supplements without explicit approval and monitoring by their transplant team. This is the most clinically important safety consideration for maitake.
Drug Interactions
| Drug / Class | Severity | Mechanism |
|---|---|---|
| Insulin, metformin, sulfonylureas, and other antidiabetic medications (Hypoglycemic agents) | moderate | Maitake SX-fraction and polysaccharide fractions demonstrate blood glucose-lowering activity through enhancement of insulin receptor signaling and improved peripheral glucose uptake. Additive hypoglycemia is possible when combined with pharmacological antidiabetic agents, particularly insulin and sulfonylureas which directly increase insulin levels or action. |
| Cyclosporine, tacrolimus, sirolimus, and other immunosuppressants (Immunosuppressants) | theoretical | Maitake's immunomodulating (immune-enhancing) properties, particularly D-fraction-mediated activation of NK cells, T cells, macrophages, and dendritic cells, could theoretically oppose the immunosuppressive effects of transplant anti-rejection medications and other immunosuppressants. Enhancement of cytokine production (IL-2, IFN-gamma, TNF-alpha) could counteract drug-induced immunosuppression. |
| Antihypertensive medications (ACE inhibitors, ARBs, calcium channel blockers, beta-blockers) (Antihypertensives) | minor | Additive blood pressure-lowering effect. Maitake contains ACE-inhibitory peptides and has demonstrated antihypertensive effects in spontaneously hypertensive rat models. Combined use with pharmaceutical antihypertensives could result in enhanced hypotensive effects. |
| Warfarin and anticoagulant/antiplatelet agents (Anticoagulants and antiplatelets) | theoretical | Theoretical concern based on maitake's effects on immune cell activation and potential indirect effects on coagulation parameters. Unlike Reishi, maitake has not been specifically demonstrated to have significant direct antiplatelet or anticoagulant activity, but the theoretical concern exists given the immunomodulatory and metabolic effects. |
Pregnancy & Lactation
Pregnancy
insufficient data
Lactation
insufficient data
There is insufficient clinical safety data on the use of Grifola frondosa extracts during pregnancy and lactation. No controlled studies in pregnant or breastfeeding women have been conducted. Traditional use does not specifically contraindicate maitake during pregnancy, and it has been consumed as a food in Japan and China by pregnant women without reported adverse effects at culinary doses. However, the immunomodulating properties of concentrated D-fraction and SX-fraction extracts raise theoretical concerns for use during pregnancy, as immune modulation could theoretically affect fetal development or pregnancy maintenance. As a precautionary measure, therapeutic doses of concentrated maitake extracts (D-fraction, MD-fraction, SX-fraction) should be avoided during pregnancy and breastfeeding unless specifically recommended by a qualified practitioner. Consumption of maitake as a culinary food in moderate amounts is likely low-risk based on historical dietary use but is not formally studied for pregnancy safety.
Adverse Effects
References
Monograph Sources
- [1] Ulbricht C, Weissner W, Basch E, Giese N, Hammerness P, Rusie-Seamon E, Varghese M, Woods J. Maitake mushroom (Grifola frondosa): systematic review by the natural standard research collaboration. J Soc Integr Oncol (2009) ; 7 : 66-72 . PMID: 19476741
- [2] Nanba H. Maitake D-fraction: healing and preventive potential for cancer. J Orthomolecular Med (1997) ; 12 : 43-49
- [3] He Y, Li X, Hao C, Zeng P, Zhang M, Liu Y, Chang Y, Zhang L. Grifola frondosa polysaccharide: a review of antitumor and other biological activity studies in China. Discov Med (2017) ; 25 : 159-176 . PMID: 28472611
Clinical Studies
- [4] Kodama N, Komuta K, Nanba H. Can maitake MD-fraction aid cancer patients?. Altern Med Rev (2002) ; 7 : 236-239 . PMID: 12126464
- [5] Kodama N, Komuta K, Nanba H. Effect of Maitake (Grifola frondosa) D-Fraction on the activation of NK cells in cancer patients. J Med Food (2003) ; 6 : 371-377 . DOI: 10.1089/109662003772519949 . PMID: 14977447
- [6] Deng G, Lin H, Seidman A, Fornier M, D'Andrea G, Wesa K, Yeung S, Cunningham-Rundles S, Vickers AJ, Cassileth B. A phase I/II trial of a polysaccharide extract from Grifola frondosa (Maitake mushroom) in breast cancer patients: immunological effects. J Cancer Res Clin Oncol (2009) ; 135 : 1215-1221 . DOI: 10.1007/s00432-009-0562-z . PMID: 19253021
- [7] Konno S, Tortorelis DG, Fullerton SA, Samadi AA, Hettiarachchi J, Tazaki H. A possible hypoglycaemic effect of maitake mushroom on Type 2 diabetic patients. Diabet Med (2001) ; 18 : 1010 . DOI: 10.1046/j.1464-5491.2001.00532-5.x . PMID: 11903406
Traditional Texts
- [8] Zhao F, Guo Z, Ma ZR, Ma LL. Antitumor activities of Grifola frondosa (Maitake) polysaccharide: A meta-analysis based on preclinical evidence and quality assessment. J Ethnopharmacol (2021) ; 280 : 114395 . DOI: 10.1016/j.jep.2021.114395 . PMID: 34271115
Pharmacopeias & Reviews
- [9] Chen Y, Liu D, Wang D, Lai S, Zhong R, Liu Y, Yang C, Liu B, Sarker MR, Zhao C. Bioactive Ingredients and Medicinal Values of Grifola frondosa (Maitake). Foods (2021) ; 10 : 95 . DOI: 10.3390/foods10010095 . PMID: 33466429
- [10] Batra P, Sharma AK. Unveiling the full spectrum of maitake mushrooms: A comprehensive review of their medicinal, therapeutic, nutraceutical, and cosmetic potential. Heliyon (2024) ; 10 : e30254 . DOI: 10.1016/j.heliyon.2024.e30254
Last updated: 2026-03-02 | Status: review
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