Agaricus Blazei

Agaricus subrufescens Peck

Sources

19 listed

Best forFor anyone curious about the almond mushroom in the kitchen, as a powder or as one of the best known medicinal mushroom supplements. It is a food, not a treatment, and the liver case reports with concentrated extracts belong in any decision to take one.

Clinical evidence

Emerging

Real World Significance

21Modern only, no premodern tradition

Breadth 17 Depth 2 Density 30 Convergence 25 Continuity 55

SafetyUse with cautionEdible for most people when cooked, but concentrated extracts have been linked to severe liver injury with two deaths, and the mushroom inhibits CYP3A4 in vitro, a possible drug interaction, may lower blood sugar, acts like oestrogen in the laboratory and can carry inorganic arsenic, so it is rated caution rather than safe.

Tradition

Folk medicine

Common preparations

PowderCapsuleExtractTea infusion

In short

Summary of findings for quick reference

The almond mushroom is Agaricus subrufescens, described by Charles Horton Peck in 1893 and sold as a market mushroom in the eastern United States in the late 19th century. The trade name Agaricus blazei goes back to a misidentification of Brazilian material in 1967. Its career as a medicinal mushroom began in 1960, when a grower found it near Piedade in Brazil, and took off in Japan, where it became himematsutake. No ancient, Hildegard or classical Chinese source mentions it, so its tradition is young and goes back only to the late 19th century.

Interest rests on its beta-glucans, highly branched beta-1,3 and beta-1,6 glucans that activate monocytes, natural killer cells and dendritic cells in cell culture and in mice. In people the record is thin. In 39 women with gynaecological cancer on chemotherapy, an extract went along with higher natural killer cell activity and fewer complaints such as poor appetite and weakness. In a placebo-controlled trial with 72 people with type 2 diabetes, 1500 mg of extract a day on top of metformin and gliclazide lowered insulin resistance over 12 weeks. The most rigorous trial, in 40 patients with multiple myeloma, shifted immune markers but changed neither treatment response nor survival.

In the EU the fruiting body is an ordinary food, with no herbal medicine monograph and no authorised health claim. Cooked, it is edible for most people, and cooking lowers its natural agaritine, a hydrazine compound that damages DNA in laboratory tests. The risk lies in concentrated extracts. In 2006 Japanese cancer doctors reported three patients with severe liver damage while taking an extract, two of whom died of fulminant hepatitis, and in one woman the damage returned when she started again. The mushroom also inhibits the drug-processing enzyme CYP3A4 in vitro, may lower blood sugar and acts like oestrogen in the laboratory. With liver disease, avoid extracts. If you take several medicines, have a hormone-sensitive condition or are in cancer treatment, talk to your doctor first.

Clinical evidence ↔ Historical significance

We display two separate evidence categories: clinical evidence from modern trials and historical significance from documented healing tradition. Both are valuable, but they answer different questions.

In every encyclopedia entry we evaluate two distinct categories of evidence. Clinical evidence as used in trials meets a narrower but scientifically essential bar. At the same time, the hundreds of thousands of plant species worldwide have only partially been captured and tested in modern studies.

Alongside the trial picture our researchers compile a comprehensive overview of where and since when a plant has been used across different traditions of natural medicine. When a plant has been used as a medicinal plant in many cultures across many generations, that historical significance deserves to be visible too.

Our position: a truly informative overview emerges only when both categories sit side by side. We communicate transparently what counts as what.

Overview

Almond mushroom is the common name of Agaricus subrufescens Peck, the mushroom sold around the world as Agaricus blazei. It belongs to the Agaricaceae, the family of the ordinary button mushroom, and its name is no marketing invention. The fresh flesh smells of marzipan, and analyses find its aroma made up mostly of aromatic compounds such as benzaldehyde, the molecule that also gives bitter almonds their scent. The part used is the fruiting body, cooked as a mushroom, dried and ground, or made into hot water and alcohol extracts. What made it famous are the polysaccharides of its cell walls, above all highly branched beta-1,3 and beta-1,6 glucans, which act on immune cells in the laboratory.

Its story is short and full of detours. In the late 19th century growers in the eastern United States raised it as a market mushroom, then it disappeared from the trade. In 1960 a grower found it again near Piedade in Brazil, in 1965 it reached Japan, and there, as himematsutake, it became one of the most popular remedies among cancer patients. In EU law the fruiting body is simply an ordinary food. The human trials are few and small, the most rigorous one found no effect on survival, and concentrated extracts have been linked to severe liver damage, including two deaths.

History

For a mushroom with such a modern career, its scientific story starts surprisingly early. The American mycologist Charles Horton Peck described Agaricus subrufescens in 1893 in his report as New York State Botanist, partly from mushrooms that were already being grown for the table. In the late 19th century it was cultivated in the eastern United States and sold as a popular market mushroom, and early in the 20th century it faded from commerce. Nothing links it to the herbals of antiquity, to Hildegard of Bingen or to the classical Chinese materia medica. Its fame as a medicinal mushroom belongs entirely to the last sixty years.

The second life began in Brazil. In 1960 the grower Takatoshi Furumoto found an almond-scented mushroom near the village of Piedade, in the Atlantic Forest highlands of São Paulo State, and in 1965 he sent it to Japan for study. In 1967 the Belgian botanist Heinemann identified it as Agaricus blazei, a name William Murrill had given in 1945 to a different mushroom from Florida. In Japan it became himematsutake, the princess matsutake, and by the mid 2000s it was one of the most popular complementary remedies among Japanese cancer patients. Brazilians call it cogumelo do sol, mushroom of the sun, and cogumelo de Deus, mushroom of God.

The name took longer to settle than the trade. In 2002 Solomon Wasser and colleagues showed that the Brazilian mushroom was not Murrill's Agaricus blazei and renamed it Agaricus brasiliensis, a name a different species had carried since 1830. In 2005 Richard Kerrigan, an American mushroom scientist who had grown Brazilian strains since 1992, settled the question with DNA analysis and crossing experiments. The Brazilian mushroom is interfertile with North American Agaricus subrufescens and is the same species, and wild finds from western Europe, described as Agaricus rufotegulis, appear to belong to it as well. Peck's name of 1893 therefore has priority, and the EU novel food catalogue now states that Agaricus blazei should no longer be used for the cultivated mushroom.

Mechanism

Almost everything known about how the almond mushroom acts comes from the laboratory. Its fruiting body is rich in highly branched beta-1,3 and beta-1,6 glucans and in protein-bound polysaccharides. In cell culture these bind receptors on innate immune cells, among them dectin-1, toll-like receptor 2 and the CD11b and CD18 complex, and set monocytes, macrophages, natural killer cells and dendritic cells to work, which then release signalling molecules called cytokines. In mice, extracts slowed several kinds of tumour, protected against infection and calmed allergic airway inflammation by rebalancing Th1 and Th2 responses. These are laboratory and animal findings, and in people they have not yet turned into a proven benefit.

The same chemistry has a less welcome side. Like the button mushroom, the almond mushroom contains agaritine, a hydrazine compound that damages DNA in laboratory tests, and related hydrazines have caused tumours in animals. Japanese researchers measured 112 to 1836 micrograms of agaritine per gram of dried material in Agaricus foods and products. What such amounts do in people has not been established. Mushrooms also take up elements from the ground they grow in, and laboratory samples of almond mushroom have contained high levels of inorganic arsenic.

The human evidence fits on a short list, and most of it comes from small studies of commercial products. In Korea in 2004, Ahn and colleagues followed 100 women with cervical, ovarian or endometrial cancer through chemotherapy. The 39 who also took an extract called Agaricus blazei Murill Kyowa had statistically significantly higher natural killer cell activity than the 61 who did not, and reported better appetite, less hair loss, steadier mood and less weakness, while other immune measures did not differ. The abstract does not describe randomisation or blinding. In Taiwan in 2007, Hsu and colleagues randomly assigned 72 people with type 2 diabetes, all already taking metformin and gliclazide, to 1500 mg of extract or a cellulose placebo a day. After 12 weeks the 29 analysed in the mushroom group had statistically significantly lower insulin resistance than the 31 on placebo (HOMA-IR 3.6 against 6.6), and their adiponectin, a hormone from fat tissue linked to insulin sensitivity, had risen by a fifth.

The most rigorous test is also the most sobering. At Oslo University Hospital, Tangen and colleagues randomly assigned 40 patients with multiple myeloma, before high dose chemotherapy and stem cell transplantation, to 60 ml a day of AndoSan or a coloured water placebo for about seven weeks, double blind. AndoSan is a Japanese extract of 82 per cent almond mushroom with some lion's mane and maitake. The immune system clearly noticed it. Regulatory T cells and plasmacytoid dendritic cells rose in the harvested stem cells, and blood levels of IL-1ra, IL-5 and IL-7 went up. The disease did not. Treatment response, time to the next treatment and survival showed no statistically significant difference, with a mean survival of 50.7 months against 47.4 months on placebo.

The same Norwegian group also tested AndoSan in inflammatory bowel disease. In two single-blind trials published in 2016, each with 50 patients who kept their usual medication, 21 days of the extract improved symptom and fatigue scores in ulcerative colitis statistically significantly more than placebo, while in Crohn's disease symptoms improved within the AndoSan group but not statistically significantly more than under placebo. Faecal calprotectin, a marker of gut inflammation, did not change in either trial, and two of the authors hold patents and shares tied to AndoSan. On tolerability, a Japanese phase I study gave 78 cancer survivors in remission 1.8 to 5.4 g of almond mushroom powder a day for six months. Nine had side effects, mostly nausea and diarrhoea, one developed liver dysfunction attributed to a food allergy, and none of these problems rose with the dose. Taken together, the human studies are small, short and mostly built on commercial products.

Evidence

5 Outcomes evaluated. Sorted by grade.

Outcome	Class	Grade	Effect	Studies
Innate immune modulation (beta-glucans)In vitro and animal models	Traditional	I	Laboratory and animal findings only
Natural killer cell activity and quality of life during chemotherapyWomen with cervical, ovarian or endometrial cancer on chemotherapy (100 women, 39 took the extract)	Emerging	I	One small comparison study	1 study
Treatment response and survival in multiple myelomaMultiple myeloma patients during high dose chemotherapy and stem cell transplantation (randomised, double-blind, 40 people)	Emerging	I	No difference in response or survival	1 study
Insulin resistance in type 2 diabetes (add-on to metformin and gliclazide)Adults with type 2 diabetes already on metformin and gliclazide (randomised, 72 people, 60 analysed)	Emerging	I	One small add-on trial	1 study
Symptoms, fatigue and quality of life in inflammatory bowel disease (AndoSan added to usual treatment)Adults with mild to moderate ulcerative colitis or Crohn's disease (two randomised single-blind trials, 50 each)	Emerging	I	Two small trials, mixed results	2 studies

Key studies

The studies that matter.

Randomised controlled trial · 2015 · 40 participants
In Oslo, 40 patients with multiple myeloma took 60 ml a day of AndoSan, an extract of 82 per cent almond mushroom, or a placebo for about seven weeks around high dose chemotherapy and stem cell transplantation, double blind. Immune measures moved, with more regulatory T cells and higher IL-1ra, IL-5 and IL-7. Treatment response, time to the next treatment and survival did not differ (mean survival 50.7 against 47.4 months). It is the most rigorous trial of the mushroom, and it found no clinical benefit.
Tangen JM, Tierens A, Caers J, Binsfeld M, Olstad OK, Trøseid AM, Wang J, Tjønnfjord GE, Hetland G. Tangen JM, Tierens A, Caers J, et al. Immunomodulatory effects of the Agaricus blazei Murrill-based mushroom extract AndoSan in patients with multiple myeloma undergoing high dose chemotherapy and autologous stem cell transplantation: a randomized, double blinded clinical study. Biomed Res Int. 2015;2015:718539. doi:10.1155/2015/718539
Randomised controlled trial · 2007 · 72 participants
In Taiwan, 72 adults with type 2 diabetes who were already taking metformin and gliclazide were randomly assigned to 1500 mg of extract or a cellulose placebo daily for 12 weeks, double blind. Insulin resistance (HOMA-IR) ended statistically significantly lower with the mushroom, 3.6 against 6.6, and adiponectin rose by 20 per cent while it fell by 12 per cent under placebo. Only 60 people were analysed, so it is one small, short trial and a signal rather than a settled effect.
Hsu CH, Liao YL, Lin SC, Hwang KC, Chou P. Hsu CH, Liao YL, Lin SC, Hwang KC, Chou P. The mushroom Agaricus blazei Murill in combination with metformin and gliclazide improves insulin resistance in type 2 diabetes: a randomized, double-blinded, and placebo-controlled clinical trial. J Altern Complement Med. 2007;13(1):97-102. doi:10.1089/acm.2006.6054
Randomised controlled trial · 2016 · 50 participants
In Oslo, 50 people with mild to moderate ulcerative colitis took AndoSan or a placebo for 21 days alongside their usual treatment, in a single-blind trial. Symptom and fatigue scores improved statistically significantly more with AndoSan, while faecal calprotectin, a marker of gut inflammation, did not change. The trial was short and analysed per protocol, two authors hold patents on the product, and the parallel trial in Crohn's disease found no statistically significant difference from placebo, so it counts for little on its own.
Therkelsen SP, Hetland G, Lyberg T, Lygren I, Johnson E. Therkelsen SP, Hetland G, Lyberg T, Lygren I, Johnson E. Effect of a medicinal Agaricus blazei Murill-based mushroom extract, AndoSan, on symptoms, fatigue and quality of life in patients with ulcerative colitis in a randomized single-blinded placebo controlled study. PLoS One. 2016;11(3):e0150191. doi:10.1371/journal.pone.0150191
Controlled trial · 2004 · 100 participants
In Korea, 100 women with cervical, ovarian or endometrial cancer were followed through chemotherapy, and 39 of them also took an Agaricus blazei extract. Natural killer cell activity was statistically significantly higher in that group, and appetite, hair loss, mood and weakness were better, while other immune measures did not differ. Unequal groups and no described randomisation make it an early, weak signal.
Ahn WS, Kim DJ, Chae GT, Lee JM, Bae SM, Sin JI, Kim YW, Namkoong SE, Lee IP. Ahn WS, Kim DJ, Chae GT, et al. Natural killer cell activity and quality of life were improved by consumption of a mushroom extract, Agaricus blazei Murill Kyowa, in gynecological cancer patients undergoing chemotherapy. Int J Gynecol Cancer. 2004;14(4):589-594. doi:10.1111/j.1048-891X.2004.14403.x
Case report · 2006 · 3 participants
Japanese oncologists described three patients with advanced cancer who developed severe liver damage while taking an Agaricus blazei extract, and two of them died of fulminant hepatitis. In one woman liver function recovered after she stopped and worsened again when she restarted. A case report cannot prove cause, but this rechallenge makes it the core of the liver warning for concentrated extracts.
Mukai H, Watanabe T, Ando M, Katsumata N. Mukai H, Watanabe T, Ando M, Katsumata N. An alternative medicine, Agaricus blazei, may have induced severe hepatic dysfunction in cancer patients. Jpn J Clin Oncol. 2006;36(12):808-810. doi:10.1093/jjco/hyl108

Usage

Forms and preparation

In the kitchen the almond mushroom is cooked like any cultivated mushroom. Its somewhat sweet flavour and marzipan scent suit soups and sauces, and dried slices can be soaked and simmered into a fragrant broth or tea. Cooking is worth it, because heat lowers agaritine, but a good part of it passes into the cooking liquid, so a broth is not free of it. As a supplement it comes freeze-dried, as powder, in capsules and as liquid or dried extracts, usually made with hot water, which draws out the beta-glucans, and sometimes also with alcohol for other constituents. Extracts are concentrated products, not a casual food, and the reported cases of liver injury involved extracts rather than the cooked mushroom. Products differ widely in how they are made and how much beta-glucan they contain, and some are blends. AndoSan, the extract used in the Norwegian trials, is only 82 per cent almond mushroom. Laboratory samples have contained high levels of inorganic arsenic, so choose a supplier that tests for heavy metals and check the species name on the label.

Dosage

There is no official dose, because in EU law the almond mushroom is a food, and no authority sets doses for foods. The studies used very different products and amounts, for example 1500 mg of extract a day in the diabetes trial, 60 ml of the liquid extract AndoSan a day in the myeloma trial and 1.8 to 5.4 g of powder a day in a six month safety study. These were research protocols, not recommendations. If you use a supplement, the label is the practical reference. Because of the liver case reports, use concentrated extracts with care, avoid them with liver disease, and tell your doctor if you take several medicines or are in cancer treatment.

Special populations

Safety in pregnancy and breastfeeding has not been established, so avoid concentrated extracts during that time. With liver disease, avoid concentrated extracts because of the documented liver cases. If you are in cancer treatment or take several medicines, talk to your doctor first, since the mushroom inhibits CYP3A4 in the laboratory and may lower blood sugar. It also acts like oestrogen in laboratory tests, so take care with hormone-sensitive conditions. No regulator has defined special groups, because it is sold as a food, not as a registered herbal medicine.

Safety

Safety profile

Cooked in the kitchen, the almond mushroom is edible for most people. Cooking is still worth doing, because it lowers agaritine, a hydrazine compound that damages DNA in laboratory tests. In tests on its cultivated relatives, frying removed about a third to two thirds, while five minutes of boiling washed about half into the cooking water, so a broth or tea keeps much of it. Regulators have also stepped in over commercial products. In 2006 Japan's health ministry had three Agaricus products tested for toxicity. One of them, a granule of Agaricus with its cell walls broken open, was the only one to test positive in two of three laboratory tests for damage to genetic material, and in rats it acted as a tumour promoter, speeding up cancers set off by other substances. The ministry asked the seller to stop sales and recall it, while noting that such a finding in rats does not show that the product causes cancer in people. The cautions in this entry apply above all to concentrated extracts and supplements. No regulator has issued an official list of contraindications, so this safety picture is built from case reports, trials and clinical references. The most serious caution concerns the liver. In 2006 doctors at Japan's National Cancer Center Hospital East described three patients with advanced cancer who developed severe liver damage while taking an Agaricus blazei extract. Two died of fulminant hepatitis. In the third, liver function recovered after she stopped and worsened again when she restarted. In 2013 a Japanese team reported two more cases of drug-induced liver injury whose tissue looked like autoimmune hepatitis, both in people who were also taking a second supplement. People with liver disease should avoid concentrated extracts. In the laboratory the mushroom inhibits CYP3A4, an enzyme that breaks down many medicines, and shows oestrogen-like activity. It may also lower blood sugar. If you take several medicines or blood sugar lowering treatment, have a hormone-sensitive condition or are in cancer treatment, talk to your doctor first. Safety in pregnancy and breastfeeding has not been established. Stop at once and seek medical advice if you notice tiredness, nausea, dark urine, pain in the upper abdomen or yellowing of the skin or eyes.

Drug interactions

No regulator has published an interaction list for the almond mushroom. In vitro it inhibits CYP3A4, an enzyme that breaks down many medicines, and Memorial Sloan Kettering Cancer Center notes that the clinical relevance has yet to be determined. Take care with medicines that depend on this enzyme and have a narrow safety margin. The mushroom may lower blood sugar, and in the diabetes trial it was taken on top of metformin and gliclazide, so if you take blood sugar lowering medicines, keep an eye on your levels. Because of the liver case reports, combine concentrated extracts with other medicines or supplements that strain the liver only after talking to your doctor. These cautions rest on laboratory work and case reports, not on interaction studies in people.

Contraindications

Hypersensitivity to mushrooms: anyone who reacts to mushrooms should avoid it. Liver disease: avoid concentrated extracts, given the case reports of severe liver injury that include two deaths. Pregnancy and breastfeeding: concentrated extracts are best avoided, because safety has not been established. Hormone-sensitive conditions: caution, because the mushroom shows oestrogen-like activity in the laboratory. Ongoing cancer treatment or multiple medicines: consult a doctor before using a concentrated extract because of a possible CYP3A4 interaction and the liver case reports.

Side effects

In a six month study with 78 cancer survivors taking 1.8 to 5.4 g of powder a day, about one in eight had side effects, mostly nausea and diarrhoea. Allergic reactions such as an inflamed, swollen lip (cheilitis) have been reported. Most serious are raised liver enzymes and liver injury, described in case reports with concentrated extracts and including two deaths from fulminant hepatitis in cancer patients. Stop and seek medical advice if signs of liver trouble appear, such as tiredness, nausea, dark urine, abdominal pain or yellowing of the skin or eyes.

Look-alikes

Botany

Family

Agaricaceae

Native regions

Northeastern United States and Canada (type range), Brazil (Piedade region, São Paulo State, where it was popularised), Japan (large scale cultivation), Now cultivated worldwide

Harvest window

Cultivated fruiting bodies harvested year round; wild fruiting in late summer and autumn

Habitat

A saprotrophic mushroom that lives on rich, composted soil and leaf litter, often close to houses and gardens. Peck described it from the northeastern United States, and it also grows wild in Brazil, where today's cultivated strains come from. Wild finds from western Europe, once named Agaricus rufotegulis, appear to be the same species. Commercial growers raise it on enriched or pasteurised compost, chiefly in Japan, China and Brazil. The part used is the fruiting body.

Identification & foraging

A large, sturdy gilled mushroom of the Agaricaceae. The cap starts hemispherical and opens out, covered first in silky fibres and later in small brownish scales. The gills are free of the stem and crowded, whitish at first, then pinkish and finally chocolate brown as the spores ripen, and a large ring hangs on the stem. Its best known feature is the smell, a clear note of almonds or marzipan that comes from aromatic compounds such as benzaldehyde and benzyl alcohol. Supplements use cultivated mushrooms, dried and ground or extracted.

Similar plants and look-alikes

Toxic

Yellow stainer (Agaricus xanthodermus)

A common, poisonous wild Agaricus that upsets the stomach of many people, with sweating, flushing and cramps. Cut the base of the stem and it turns bright yellow at once, and it smells unpleasantly of ink, carbolic soap or phenol rather than of almonds, especially when cooked. Because yellow stainers grow among edible Agaricus species, anyone gathering wild Agaricus to eat needs a certain identification of every single mushroom. The almond mushroom in supplements is cultivated, not foraged.

Unpleasant

Common button mushroom (Agaricus bisporus)

The everyday white or chestnut mushroom is a close relative in the same genus and a fine food, but a different species. It lacks the almond scent, and the trials described here tested almond mushroom products, not button mushrooms. If the species matters to you, check the botanical name on the label.

Deadly

Death cap and destroying angels (Amanita phalloides, Amanita virosa), deadly poisonous

Young white Agaricus are easily confused with deadly Amanitas, such as the white form of the death cap and the destroying angels, and such mistakes still kill people. In 2024 nineteen people in northeastern China were poisoned by an Amanita they had taken for the cultivated button mushroom, and two of them died of liver failure. Amanita gills stay white for life, while Agaricus gills turn pink and then chocolate brown. Never eat a wild white mushroom unless every single one has been identified by an expert.

FAQs

Is Agaricus blazei the same as Agaricus subrufescens?

Yes. The mushroom sold as Agaricus blazei is Agaricus subrufescens, described by Charles Horton Peck in 1893. In 2005 Richard Kerrigan showed with DNA analysis and crossing experiments that the Brazilian strains and the North American species are one and the same. The name Agaricus blazei belongs to a different Florida mushroom that William Murrill described in 1945, and the EU novel food catalogue now asks that it no longer be used for the cultivated one.

Is the almond mushroom approved in the EU for any health use?

No. In the EU the fruiting body counts as an ordinary food, which the novel food catalogue lists as not novel, while dried mycelium powder still needs authorisation as a novel food. There is no herbal medicine monograph, and no health claim has been authorised for it. The only authorised beta-glucan claims concern beta-glucans from oats and barley, for blood cholesterol and for blood sugar after meals.

Is the almond mushroom a risk to the liver?

Concentrated extracts can be, and it is the most serious point in this entry. In 2006 Japanese cancer doctors described three patients with advanced cancer who developed severe liver damage while taking an Agaricus blazei extract, and two of them died of fulminant hepatitis. In one woman the liver recovered after she stopped and worsened again when she restarted, which the authors read as a strong sign of a causal link. Later reports describe further drug-induced liver injury resembling autoimmune hepatitis. Case reports cannot prove cause, but with liver disease avoid extracts, and if you take several medicines or are in cancer treatment, talk to your doctor first.

What does the almond mushroom do to the immune system?

It changes immune measurements, which is not the same as protecting anyone from illness. Its beta-glucans activate immune cells in cell culture and in mice, and in people extracts have raised natural killer cell activity and shifted cytokines and immune cell counts. In the most rigorous trial, in multiple myeloma, those changes came without any difference in treatment response or survival. No immune claim is authorised for it in the EU.

Did a study show it helps with type 2 diabetes?

One small trial points that way. In Taiwan in 2007, 72 people with type 2 diabetes who were already taking metformin and gliclazide took 1500 mg of extract or a placebo daily, and after 12 weeks insulin resistance was statistically significantly lower in the mushroom group. Because both groups kept their medicines, the result shows an effect on top of treatment, not a replacement for it. It is a single small study, and diabetes medication should only ever be changed together with your doctor.

How old is the tradition of Agaricus blazei?

Younger than its reputation suggests. It was grown as a table mushroom in the eastern United States in the late 19th century and then forgotten. Its career as a medicinal mushroom began in 1960, when it was found near Piedade in Brazil, and took off in Japan as himematsutake. No ancient, medieval or classical Chinese source mentions it, so any such claim is an invention.

References

19 sources.

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Ahn WS, Kim DJ, Chae GT, Lee JM, Bae SM, Sin JI, Kim YW, Namkoong SE, Lee IP. Ahn WS, Kim DJ, Chae GT, et al. Natural killer cell activity and quality of life were improved by consumption of a mushroom extract, Agaricus blazei Murill Kyowa, in gynecological cancer patients undergoing chemotherapy. Int J Gynecol Cancer. 2004;14(4):589-594.. 2004. doi:10.1111/j.1048-891X.2004.14403.x
Kerrigan RW. Kerrigan RW. Agaricus subrufescens, a cultivated edible and medicinal mushroom, and its synonyms. Mycologia. 2005;97(1):12-24.. 2005. doi:10.3852/mycologia.97.1.12
Nagaoka MH, Nagaoka H, Kondo K, Akiyama H, Maitani T. Nagaoka MH, Nagaoka H, Kondo K, Akiyama H, Maitani T. Measurement of a genotoxic hydrazine, agaritine, and its derivatives by HPLC with fluorescence derivatization in the Agaricus mushroom and its products. Chem Pharm Bull (Tokyo). 2006;54(6):922-924.. 2006. doi:10.1248/cpb.54.922
Mukai H, Watanabe T, Ando M, Katsumata N. Mukai H, Watanabe T, Ando M, Katsumata N. An alternative medicine, Agaricus blazei, may have induced severe hepatic dysfunction in cancer patients. Jpn J Clin Oncol. 2006;36(12):808-810.. 2006. doi:10.1093/jjco/hyl108
Hsu CH, Liao YL, Lin SC, Hwang KC, Chou P. Hsu CH, Liao YL, Lin SC, Hwang KC, Chou P. The mushroom Agaricus blazei Murill in combination with metformin and gliclazide improves insulin resistance in type 2 diabetes: a randomized, double-blinded, and placebo-controlled clinical trial. J Altern Complement Med. 2007;13(1):97-102.. 2007. doi:10.1089/acm.2006.6054
Firenzuoli F, Gori L, Lombardo G. Firenzuoli F, Gori L, Lombardo G. The medicinal mushroom Agaricus blazei Murrill: review of literature and pharmaco-toxicological problems. Evid Based Complement Alternat Med. 2008;5(1):3-15.. 2008. doi:10.1093/ecam/nem007
Ohno S, Sumiyoshi Y, Hashine K, Shirato A, Kyo S, Inoue M. Ohno S, Sumiyoshi Y, Hashine K, Shirato A, Kyo S, Inoue M. Phase I clinical study of the dietary supplement, Agaricus blazei Murill, in cancer patients in remission. Evid Based Complement Alternat Med. 2011;2011:192381.. 2011. doi:10.1155/2011/192381
Hetland G, Johnson E, Lyberg T, Kvalheim G. Hetland G, Johnson E, Lyberg T, Kvalheim G. The mushroom Agaricus blazei Murill elicits medicinal effects on tumor, infection, allergy, and inflammation through its modulation of innate immunity and amelioration of Th1/Th2 imbalance and inflammation. Adv Pharmacol Sci. 2011;2011:157015.. 2011. doi:10.1155/2011/157015
Tangen JM, Tierens A, Caers J, Binsfeld M, Olstad OK, Trøseid AM, Wang J, Tjønnfjord GE, Hetland G. Tangen JM, Tierens A, Caers J, et al. Immunomodulatory effects of the Agaricus blazei Murrill-based mushroom extract AndoSan in patients with multiple myeloma undergoing high dose chemotherapy and autologous stem cell transplantation: a randomized, double blinded clinical study. Biomed Res Int. 2015;2015:718539.. 2015. doi:10.1155/2015/718539
Hisamochi A, Kage M, Arinaga T, Ide T, Miyajima I, Ogata K, Kuwahara R, Koga Y, Kumashiro R, Sata M. Hisamochi A, Kage M, Arinaga T, et al. Drug-induced liver injury associated with Agaricus blazei Murill which is very similar to autoimmune hepatitis. Clin J Gastroenterol. 2013;6(2):139-144.. 2013. doi:10.1007/s12328-013-0359-0
Therkelsen SP, Hetland G, Lyberg T, Lygren I, Johnson E. Therkelsen SP, Hetland G, Lyberg T, Lygren I, Johnson E. Effect of a medicinal Agaricus blazei Murill-based mushroom extract, AndoSan, on symptoms, fatigue and quality of life in patients with ulcerative colitis in a randomized single-blinded placebo controlled study. PLoS One. 2016;11(3):e0150191.. 2016. doi:10.1371/journal.pone.0150191
Therkelsen SP, Hetland G, Lyberg T, Lygren I, Johnson E. Therkelsen SP, Hetland G, Lyberg T, Lygren I, Johnson E. Effect of the medicinal Agaricus blazei Murill-based mushroom extract, AndoSan, on symptoms, fatigue and quality of life in patients with Crohn's disease in a randomized single-blinded placebo controlled study. PLoS One. 2016;11(7):e0159288.. 2016. doi:10.1371/journal.pone.0159288
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European Commission. European Commission. EU Novel Food Catalogue, entry POL-NF-13064: Silene vulgaris (Moench) Garcke, leaves and tender stems, not novel in food (Article 4 consultation, Spanish authority), 2025. 2025. Source
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