Agaricus blazei
A Brazilian mushroom with a large traditional following and a genuine safety caveat that gets almost no airtime.
Agaricus blazei quick facts
| Suggested dose | 1.5–3 g daily of extract. |
| How often | Daily |
| Who it's for | Weak evidence. Reishi and turkey tail have better data for the same purpose. |
Small positive trials on quality of life and immune markers in oncology. Two cautions worth knowing: some reports of liver dysfunction in cancer patients using it, and Agaricus species can accumulate cadmium and agaritine, whose significance is debated. Less well characterized than turkey tail or AHCC for the same purpose.
How Agaricus blazei actually works
Beta-glucans binding the same dectin-1 and complement receptors as other medicinal mushrooms, with unusually high beta-glucan content by dry weight. Preclinical work shows NK-cell and macrophage activation, and ergosterol derivatives contribute separate antiproliferative activity in cell models. Small human studies in patients receiving chemotherapy show changes in immune markers.
Where to get Agaricus blazei
Find Agaricus blazei on iHerb →The evidence for Agaricus blazei
Graded by what exists behind each claim.
✅ Clinically validated
- Small trials in cancer patients report improved quality of life and NK cell activity during chemotherapy.
- A trial in ulcerative colitis reported reduced disease activity.
- Overall the human evidence is thin and largely from Japan and Brazil.
📊 Correlative data
- Interest originated from an observation about a Brazilian region where the mushroom was habitually eaten and disease rates were reported to be lower — an ecological association, which is the weakest observational design there is and cannot support the claims built on it.
🧪 Theoretical / extrapolated benefits
- Beta-glucans and ergosterol derivatives with immunomodulatory activity in preclinical models.
How to read these tiers: they say how much human evidence exists, not how well something works — and ✗ flags harm, never a disappointing trial. How the evidence tiers work →
What Agaricus blazei actually does
Every other medicinal mushroom on this shelf belongs to a genus you have never eaten. This one does not. Agaricus subrufescens — sold as A. blazei Murrill and also filed as A. brasiliensis, three Latin names for one organism — is a close relative of the supermarket button mushroom, and it inherits the genus chemistry that comes with that.
The molecule that makes this page different is agaritine. It is a phenylhydrazine derivative, a glutamyl conjugate of 4-hydroxymethylphenylhydrazine, and it is genotoxic. It is measurable by liquid chromatography with tandem mass spectrometry down to 0.003 micrograms per gram, and that method has been applied across commercial mushroom samples Kondo 2006. Hydrazines are bioactivated to diazonium species that alkylate DNA; this is not an exotic worry invented for a supplement page, it is why the button mushroom itself has a small toxicology literature. No Agaricus blazei product prints an agaritine number.
The polysaccharide story is real but it is not the interesting part. The immunological work describes beta-glucans and glucomannan fractions and steroid-like ergosterol derivatives, and the review that collected it is titled, accurately, as a review of literature and pharmaco-toxicological problems Firenzuoli 2008. When the best available synthesis puts the toxicology in the title, that is the mechanism section telling you where to look.
And the human immunology was measured on a mixture. AndoSan, the fermented liquid extract used in the Norwegian inflammatory bowel disease trials, is an Agaricus-based preparation rather than a pure one Therkelsen 2016. A trial of a blend cannot attribute its result to one component, and that is a limitation of the evidence rather than a criticism of the trial.
Cell, rodent, human — and where it stops
Cells. The dendritic-cell and cytokine work is in vitro, on extracts, and it is the basis of the whole category claim Firenzuoli 2008.
Humans, and every single trial is in ill people. Ahn 2004: gynecological cancer patients receiving chemotherapy, taking an Agaricus blazei Murill Kyowa extract, with natural killer cell activity and quality of life as the outcomes Ahn 2004. Ohno 2011: a phase I study in 78 cancer patients in remission, given granulated powder at 1.8, 3.6 or 5.4 g per day orally for six months, with adverse events in 9 patients (12%), mostly digestive Ohno 2011. Therkelsen 2016: 50 patients with ulcerative colitis, 24 on AndoSan and 26 on placebo, single-blinded, for 21 days; the symptom score fell from 5.88 at baseline to 4.71 at day 14 (p = 0.002) and 4.50 at day 21 (p = 0.001) Therkelsen 2016.
The specific obstacle is the population, three times over. Cancer patients on chemotherapy, cancer patients in remission, and people with active ulcerative colitis. Those are the three rooms this product has been tested in, and the endpoints are a natural killer assay and two questionnaires. A well adult has no chemotherapy-suppressed NK activity to restore and no disease activity index to lower, so there is no version of these results that applies to them.
The second obstacle is duration versus the risk window. The efficacy trial that reported a symptom change ran 21 days Therkelsen 2016. The safety signal on this mushroom is idiosyncratic liver injury, which in the published cases followed weeks to months of use Mukai 2006. The evidence for benefit and the evidence for harm are measured on different clocks, and the shorter clock is the one generating the good news.
And the origin story is the weakest design there is. Interest in this mushroom began with an ecological observation about a Brazilian region where it was habitually eaten. An ecological correlation cannot support an individual-level claim, and the review of the field says as much Firenzuoli 2008.
Agaricus blazei — which form, and does it matter
Three Latin names, and the one on your bottle predicts nothing. Agaricus blazei Murrill, A. subrufescens and A. brasiliensis are used interchangeably in the trade and inconsistently in the literature Firenzuoli 2008. When a product category cannot agree on the species name, chemical consistency between jars is not something you should assume.
Liquid fermented extract is not powdered fruiting body. The inflammatory bowel disease work used AndoSan, a fermented liquid Therkelsen 2016; the phase I safety work used granulated powder at 1.8–5.4 g/day Ohno 2011; the oncology work used a branded Kyowa extract Ahn 2004. Three trials, three materials, and a capsule labeled only “Agaricus blazei 500 mg” is a fourth.
The processing paradox nobody mentions. Agaritine is unstable — it degrades with heat, with drying and with storage, which is why analytical methods for it are written carefully Kondo 2006. That means the premium “raw, low-temperature, freeze-dried, full-spectrum” product is precisely the preparation most likely to retain the genotoxic hydrazine, and the cheap heat-treated one is the safer material. On this mushroom the marketing signals for quality and the signals for safety point in opposite directions.
What to demand. A species identification, an extraction method, and an agaritine assay. The first two are sometimes printed. The third exists as a validated method Kondo 2006 and appears on no label sold in the West.
What would have to be true, and how you would know it was not
1. ALT and AST, and the predicted shape is bimodal rather than gradual. Predict no change at all in a well person over 8 weeks — and predict that where a change appears it is large, abrupt and unrelated to how much you took, because the published injuries are idiosyncratic rather than dose-dependent Mukai 2006 Hisamochi 2013. Draw liver enzymes before the first capsule and at 8 weeks. “A bit higher than last time” is not the pattern to expect; a transaminase in the hundreds is.
2. The prediction that cuts against the product. Predict that any immune measurement that moves is one you cannot feel. The positive human immunology here is an NK activity assay in chemotherapy patients Ahn 2004; there is no trial in which a well person felt or counted anything. If you are buying this to notice something, the evidence predicts you will not.
3. The comparison prediction. Predict that a reishi or turkey tail capsule at the same price performs identically on any endpoint you can measure at home, because for those the human evidence is larger and the liver signal is absent Firenzuoli 2008. The useful experiment is not this product against nothing; it is this product against the better-evidenced jar next to it.
4. What will fool you clinically. One of the reported liver injuries was histologically indistinguishable from autoimmune hepatitis Hisamochi 2013. If you are unwell and a clinician is working up abnormal liver tests, this supplement is a fact they need — otherwise the wrong diagnosis is the plausible one.
What nobody has tested yet
Nobody has measured how much agaritine a supplement dose delivers. The analytical method is published and validated to 0.003 micrograms per gram Kondo 2006, and the number for a 3 g daily dose of a retail extract has never been reported. That single measurement would convert an open-ended worry into arithmetic.
Nobody has run Agaricus alone against the blend. AndoSan's result belongs to a mixed preparation Therkelsen 2016. A three-arm trial — blend, Agaricus alone, placebo — would say whether this mushroom is the active ingredient of its own most cited trial.
Nobody can predict who gets the liver injury. The cases are sporadic, some occurred in patients on other agents, and one showed recovery on withdrawal and deterioration on rechallenge Mukai 2006. That rechallenge pattern is strong causal evidence and weak predictive evidence: it establishes the mushroom did it, and says nothing about who is next.
And no trial has enrolled a healthy person. Every human dataset is in cancer or colitis Ahn 2004 Ohno 2011 Therkelsen 2016. The population that actually buys this has never been studied for benefit or for harm.
Agaricus blazei — its own safety story, not its category's
This is the one common medicinal mushroom with a liver signal, and it is not a theoretical one. Three patients with advanced cancer taking an Agaricus blazei extract were reported with severe hepatic dysfunction; two developed fulminant hepatitis, liver function recovered on stopping, and deteriorated again when the extract was restarted Mukai 2006. Recovery on withdrawal plus recurrence on rechallenge is about as close to proof of causation as case reporting gets.
A second report describes drug-induced liver injury whose histology closely resembled autoimmune hepatitis Hisamochi 2013. That matters practically: the injury can imitate a chronic disease that would otherwise be treated with immunosuppression.
The stop rule, stated as a rule rather than a caution. Yellowing of the eyes or skin, dark urine, pale stool, itching, unexplained fatigue or right upper abdominal pain means stop today and get liver enzymes checked this week. Do not wait for the next bottle to finish, and tell whoever orders the test what you have been taking.
The genotoxic constituent, named. Agaritine is a phenylhydrazine present in this genus and measurable at trace levels in commercial mushrooms Kondo 2006. Daily long-term dosing of a concentrated extract is a different exposure from eating mushrooms in a meal, and nobody has quantified the difference.
Who this is a straightforward no for. Anyone with existing liver disease or abnormal liver enzymes; anyone on chemotherapy, where two of the three published hepatic cases occurred Mukai 2006; anyone taking another hepatically-loaded supplement stack. Digestive upset was the commonest adverse event in the largest safety dataset, 9 of 78 patients Ohno 2011, and is the least of the concerns here.
Sources read for this page
- Ahn WS. 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. International Journal of Gynecological Cancer 2004 · PMID 15304151
- Ohno S. Phase I Clinical Study of the Dietary Supplement, Agaricus blazei Murill, in Cancer Patients in Remission. Evidence-Based Complementary and Alternative Medicine 2011 · PMID 21584278
- Therkelsen SP. 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 · PMID 26933886
- Mukai H. An alternative medicine, Agaricus blazei, may have induced severe hepatic dysfunction in cancer patients. Japanese Journal of Clinical Oncology 2006 · PMID 17105737
- Hisamochi A. Drug-induced liver injury associated with Agaricus blazei Murill which is very similar to autoimmune hepatitis. Clinical Journal of Gastroenterology 2013 · PMID 26181451
- Kondo K. Determination of genotoxic phenylhydrazine agaritine in mushrooms using liquid chromatography-electrospray ionization tandem mass spectrometry. Food Additives and Contaminants 2006 · PMID 17071520
- Firenzuoli F. The Medicinal Mushroom Agaricus blazei Murrill: Review of Literature and Pharmaco-Toxicological Problems. Evidence-Based Complementary and Alternative Medicine 2008 · PMID 18317543
How you would know if it worked
There is no blood test for this one. That is not a criticism — it is a fact about the effect, and it changes how you should judge it.
- What to watch: Nothing here has been established well enough to score. The human evidence is thin, small, and mostly quality-of-life questionnaires in people undergoing cancer treatment — the population least able to separate one supplement from everything else happening to them at the same time.
- How long before it means anything: No useful window, and the more useful comparison is not before-and-after with this product. Reishi and turkey tail have better data for the same purpose, so the honest test is against the alternatives on the same shelf.
- What will fool you: The safety record nobody puts on the label. Of the common medicinal mushrooms this is the one with a liver signal — case reports of severe hepatotoxicity, including liver failure, in cancer patients taking Agaricus extracts. Yellowing of the eyes, dark urine, itching or right-sided abdominal pain means stop and get liver enzymes checked that week. Its reputation also rests on an ecological observation about one Brazilian region, which is the weakest study design there is.
Run it one variable at a time. Starting three things in one week means a result you cannot attribute, which is the same as no result.
Agaricus blazei — safety & side effects
- GI upset and nausea.
- Rare idiosyncratic liver injury has been reported. It is not dose-dependent and not predictable, so the practical rule is to stop and get liver enzymes checked if you develop unexplained fatigue, nausea, dark urine or yellowing of the eyes. Reports of hepatotoxicity with agaricus are more numerous than for most medicinal mushrooms, particularly in cancer patients.
- Avoid with mushroom allergy. Do not use during cancer treatment without oncology input.
The same on every page it applies to. Read it here; it is not repeated research.
- Immunostimulant — caution with autoimmune disease and with immunosuppressants, including after a transplant. Stimulating an immune system that is already attacking you is the wrong direction, and 'natural' does not change that.
Not medical advice. If you take prescription medication or have a diagnosed condition, check this against it with a pharmacist or doctor — pharmacists are underused and free.
- When to take it, and what to take it with
- Which form actually absorbs
- Who it's worth it for
- Coach Cam's stacks and notes
- Fasted or with food, and when in the day
- Morning or night, and why that window
- Around training, or deliberately away from it
- What it must not share a window with
Everything above is free and stays free. Skool is where it becomes a plan — Agaricus blazei in an order, with the rest of what you're running.
Unlock in Skool — $10/mo →Bloodwork to run alongside Agaricus blazei
Baseline first, then again at 8–12 weeks.
| Marker | What it’s watching for |
|---|---|
| Complete Blood Count (CBC) with Differential | White cells and their differential — the actual immune measurement |
| Vitamin D (25-Hydroxy) | The deficiency with the most credible immune evidence |
| Zinc, Plasma | Real deficiency impairs immune function; excess doesn't help |
| Comprehensive Metabolic Panel (CMP) | Liver and kidney, since 'detox' is what those two organs do |
The Frequent Illness & Immune Resilience panel covers these in one order — 8 markers, $97.65 with the discount applied.
Check results you already have → · All 103 markers A–Z
Agaricus blazei — frequently asked questions
What is Agaricus blazei?
A Brazilian mushroom with a large traditional following and a genuine safety caveat that gets almost no airtime.
What is the suggested dose of Agaricus blazei?
1.5–3 g daily of extract. This is a general reference for education only — statements have not been evaluated by the FDA and this is not medical advice.
Where can I find Agaricus blazei dosing and the full breakdown?
The suggested dose and the full evidence — clinical, correlative and theoretical — are on this page. What's inside Skool is when to take it, which form actually absorbs, the brand worth buying and Coach Cam's stacks.
Where can I buy Agaricus blazei?
Coach Cam sources Agaricus blazei from vetted, top-rated brands on iHerb — use the buy link on this page.
What Agaricus blazei is used for
Agaricus blazei appears under 1 goal in the goal router.
Related Immune & Detox supplements
Where this goes next
The pages here are the frameworks. The protocols — the dosing, the order to correct things in, the week-by-week schedule and what to retest — are inside Skool.