Medicinal Mushrooms and Prostate Health: What Was Measured in Humans — and What Came Out

Q: Does reishi help with prostate symptoms?

This is the one topic on our site where the answer is not “never tested.” In two randomized, double-blind trials, 138 men in total, 6 mg a day, 12 weeks, the prostate symptom score fell 2.1 points — a difference of 1.18 versus placebo. The threshold for a clinical responder is 3 points, and the threshold men can feel is 5.26. In other words: a statistically real improvement, and too small for most men to feel.

Q: What exactly did not change in the trials?

Peak urine flow, mean flow, post-void residual, prostate volume, serum PSA, serum testosterone, and the quality-of-life score. Seven measures, and not one of them moved. And urine flow was a primary endpoint in the large trial — meaning half of the trial’s declared aim was not achieved, and most citations online leave that out.

Q: Can reishi hide prostate cancer on a PSA test?

There is no evidence of that. With finasteride and dutasteride it is a documented problem — the PSA reduction lasts up to 48 months, and any rise from the nadir should be regarded as suspicious. With reishi, PSA simply did not change in the two trials, and it did not move either in 15 men with recurrent prostate cancer who took it for six months. But precisely because the question gets asked: there is no substitute for medical monitoring.

Q: Is your extract the one that was tested in the trials?

No. The extract in the trials is a specific ethanol extract chosen from a screen of 19 mushrooms, at a dose of 6 mg a day. We sell a different extract, at a different concentration and in a different form, and it has not been tested in any prostate trial. The same research group showed itself that a reishi extract in a different solvent gives “weak” enzyme inhibition — the preparation decides, not the name of the mushroom.

Q: Reishi blocks DHT — doesn’t that prove it works?

The 5-alpha-reductase inhibition was measured in rat liver microsomes in a dish (an IC₅₀ of 10.6 micromolar for ganoderic acid DM). In men who took the extract for 12 weeks, even at a dose of 60 mg, blood testosterone did not change — and DHT was never measured in any human trial at all. If the inhibition were translated into the body, something would have moved in the blood. Nothing moved.

Q: What about lion’s mane, cordyceps and turkey tail?

They have never been tested for prostate symptoms — the direct search returns zero results for all three. What exists: prostate cancer cells in a dish (lion’s mane, turkey tail), isolated rat bladder strips (cordyceps), and rats exposed to microplastics. Not one man has been measured.

Q: Does cordyceps really improve sexual function and testosterone?

It was measured in diabetic rats and in mouse Leydig cells. In men — never: there is not a single trial in the world that measured erectile function in a human being after any mushroom, and no trial in men that measured sperm quality after cordyceps. The nickname “Himalayan Viagra” appears as a keyword in a paper titled “Myths and Realities.”

Q: I take tamsulosin or finasteride. Can I take reishi alongside?

That is a question for your doctor, and it is not a polite way of saying it — there is simply no study. A direct search for an interaction between the mushrooms and tamsulosin, finasteride or dutasteride returns zero results, and the safety base in men with prostate symptoms is 138 men for up to 12 weeks, with no drug alongside. Absence of evidence of harm is not evidence of absence of harm.

Written by Shlomi Hayun, Head Grower · Scientifically reviewed by Dr. Evyatar Shaulsky, Ph.D., Yale graduate · Updated: September 11, 2026

In brief5 points · 1-minute read

Reishi is the only medicinal mushroom tested in randomized trials for prostate symptoms: 138 men, 6 mg a day, 12 weeks.
The symptom score dropped 2.1 points, a 1.18 difference versus placebo; the responder threshold is 3 and men notice about 5.26.
Urine flow, post-void residual, prostate volume, PSA and testosterone stayed unchanged in both trials.
The research extract is not a commercial product; no prostate trial has tested any extract you can buy, including ours.
Lion's mane, cordyceps and turkey tail have never been studied for prostate enlargement; prostate cancer has zero randomized mushroom trials.

Questions about this article? Ask the Triterra bot

Reishi (Ganoderma lucidum), the lingzhi of traditional Chinese medicine, is the only medicinal mushroom in the world tested in a randomized, placebo-controlled trial in men with prostate symptoms. The result: the symptom score fell 2.1 points, a difference of 1.18 versus placebo — below the threshold men can feel. And not one objective measure moved: not urine flow, not prostate volume, not PSA, not testosterone.

The kinds of evidence that do exist, from closest to a person to farthest: two randomized, double-blind trials in men with lower urinary tract symptoms, 138 participants in total; one open-label study in men with recurrent prostate cancer, negative; inhibition of the enzyme 5-alpha-reductase in rat liver microsomes; the prostates of castrated rats; and prostate cancer cells in culture. On lion’s mane, cordyceps and turkey tail in the context of prostate enlargement — zero, at every grade of evidence.

Why this page is different from what you will find online about mushrooms and the prostate. Online you will find “clinical studies have proven that reishi treats prostate enlargement” — and this is the one place on our site where the claim rests on a real trial in human beings. That is exactly why we wrote it through to the end: how far the score fell, what threshold men can actually feel, and what did not move. We ran 12 queries on PubMed: 5 returned zero results, and of the 13 publications on reishi and prostate enlargement, only 2 are trials in humans. We built a table of 9 mushrooms across 7 axes of evidence — 63 cells, 41 of them “nothing at all.” 39 of the sources we read are below, each with its link.

Key takeaways

What was measured in men: 88 men over age 49, reishi extract 6 mg a day, 12 weeks — the symptom score (IPSS) fell 2.1 points; difference versus placebo 1.18 (95% CI: 0.62–1.74). A second trial in 50 men confirmed the direction.
What that is worth: the accepted threshold for a “clinical responder” is 3 points; the threshold men themselves report as “slightly improved” is 5.26. 1.18 is less than 40% of the first and less than a quarter of the second.
What did not move: peak urine flow, mean flow, post-void residual, prostate volume, PSA, testosterone and quality of life — 7 measures, zero change.
Prostate cancer: zero randomized trials anywhere in the world, for any mushroom. 15 men with recurrent cancer took reishi for six months — zero PSA responses. A shiitake extract failed the same way in 62 men.
Lion’s mane, cordyceps, turkey tail: never tested for prostate enlargement. Erectile function after any mushroom — never measured in a human being.

Do medicinal mushrooms help the prostate?

Reishi was tested, and something moved — but less than men can feel. In two randomized, double-blind trials, the prostate symptom score fell 2.1 points, 1.18 versus placebo, when the threshold for a clinical responder is 3. Urine flow, prostate volume, PSA and testosterone did not change. For the other mushrooms — zero measurements in men.

This is the only page in our series of condition pages where the answer is not “never tested.” That also makes it the page where cheating is easiest: all it takes is to quote “IPSS fell significantly” and stop there. We sell reishi, and that is exactly why we bring both halves — the drop that was measured, and the threshold it did not cross. The page walks through the two trials, through what the extract that was tested is and is not, through PSA and prostate cancer, through sexual function, and through what a man at this age really needs to know before he adds a supplement to a medication.

What was measured for each mushroom — and in which system?

The table sorts nine mushrooms along four axes: prostate symptoms, PSA and testosterone in men, prostate cancer, and sexual function and fertility. Only one row contains a randomized trial in humans — reishi. Three rows contain a negative open-label study in prostate cancer. The rest: cells in culture, rats, or nothing.

Mushroom	Prostate symptoms (BPH/LUTS)	PSA and testosterone in men	Prostate cancer	Sexual function and fertility
Reishi (Ganoderma lucidum)	2 randomized trials, 138 men — IPSS fell 1.18 versus placebo; objective measures unchanged	Measured — did not move	Open-label study in 15 men — zero PSA responses; cells in culture	Rats and mice only
Lion’s mane (Hericium erinaceus)	Nothing at all	Nothing at all	Cells in culture	Rats (microplastics)
Cordyceps	Isolated rat bladder strips	Nothing at all	Nothing at all	Diabetic rats; mouse Leydig cells; human sperm in a dish
Turkey tail (Trametes versicolor)	Nothing at all	Nothing at all	One cell line responded, another did not	Nothing at all
Shiitake (Lentinula edodes)	Nothing at all	Open-label study	Open-label study in 62 men — “not effective”	Nothing at all
Maitake (Grifola frondosa)	Nothing at all	Nothing at all	Cells in culture; dogs with lymphoma — zero responses	Nothing at all
Agaricus (Agaricus blazei)	Nothing at all	Open-label study	Open-label study in 32 men — zero PSA responses	Nothing at all
Chaga (Inonotus obliquus)	Nothing at all	Nothing at all	Nothing at all	Cells in culture — direction ambiguous
White button mushroom (Agaricus bisporus)	Nothing at all	Uncontrolled phase I trial	Phase I trial in 36 men, 8–14 grams a day, 11% response	Nothing at all

What exactly did the two trials in men measure — and what came out?

The large trial: 88 men over age 49 with mild to moderate lower urinary tract symptoms, an ethanol extract of reishi at 6 mg a day versus placebo, 12 weeks. The IPSS fell 2.1 points; the difference versus placebo was 1.18 (95% CI: 0.62–1.74; P<0.0001). Quality of life, urine flow, post-void residual, prostate volume, PSA and testosterone — no change.

One detail that most citations leave out deserves attention: the trial had two primary endpoints — the change in IPSS and the uroflowmetry measures, that is, urine flow. Half of the primary endpoint did not move. The IPSS is a questionnaire the patient fills in; urine flow is a measurement taken by an instrument. The questionnaire improved slightly; the instrument saw nothing. The authors themselves closed with a call for “further evaluation on a large scale and over the long term” — not with the announcement of a treatment.

The second trial, a pilot by the same group, compared placebo (12 men) with 0.6 mg (12), 6 mg (12) and 60 mg (14) a day, in men aged 50 and over with an IPSS of 5 or more and PSA below 4 ng/mL. Here too: significance in the change in IPSS between the groups at weeks 4 and 8, and no change in urine flow, post-void residual, prostate volume or PSA. The dose set as recommended: 6 mg. The pilot’s abstract reports no effect size, P value or confidence interval for the IPSS — so any number online attributed to “the dose-ranging trial” did not come from its abstract. Both trials were well tolerated, with no serious adverse effects. Take care not to mix them up: “88 men” belongs to the 6 mg versus placebo trial; “0.6, 6 and 60 mg” belongs to the pilot of 50.

Is 1.18 points on the IPSS a lot?

No. The accepted threshold for a “clinical responder” on the IPSS is 3 points, and when researchers measured the threshold men themselves report as “slightly improved” — it came out at 5.26 points. The difference measured with reishi, 1.18, is less than 40% of the lenient threshold and less than a quarter of the patient-centered one. The improvement is statistically real, and too small for most men to feel.

This is the chapter that decides whether the page is honest, so here are the numbers in full. A 2025 study calculated the minimal important difference (MID) for the IPSS by a patient-centered method: 82 men with lower urinary tract symptoms who reported after 12 weeks “slightly improved” — and the mean change among them was 5.26 points (95% CI: 4.38–6.13). In moderate symptoms the threshold was 4.00, and in severe symptoms 8.23. The reishi difference, 1.18, sits below the lower bound of the confidence interval even in the mildest subgroup. The classic threshold, 3 points, appears in clinical trials as the definition of the “minimal clinically important difference.”

And one reference point that is genuinely impressive: the Cochrane review of saw palmetto (Serenoa repens) — the most widely used plant in the world for the prostate — summed up 17 trials in 2,008 men and found it no better than placebo: mean difference in IPSS −0.16 points (95% CI: −1.45 to 1.14), and a responder rate (a drop of 3 points or more) of 43% versus 44% on placebo. The reishi confidence interval (−1.74 to −0.62) sits entirely inside the confidence interval of the plant declared “no better than placebo.” By contrast, a commercial hexanic extract of the same saw palmetto, in a meta-analysis of 27 studies in 5,800 men, improved IPSS by 5.73 points from baseline and raised urine flow by 2.75 mL per second — that is what a botanical intervention that does cross the threshold looks like, and no mushroom preparation has got there.

The extract that was tested is not the extract you buy

The extract in the two trials was chosen from a screen of 19 mushrooms as the one with the strongest 5-alpha-reductase inhibition, extracted in ethanol, and given at 6 mg a day. It is a specific research extract. The extract we sell is a different extract, at a different concentration and in a different form — and it was not tested in that trial, nor in any prostate trial.

This chapter is the difference between a page that rests on research and a page that steals it. The evidence on reishi and the prostate is valid for the extract that was tested — and for it alone. The same research group showed itself how much this depends on the preparation: in 2009 it reported that 30% ethanol extracts of reishi showed “weak” 5-alpha-reductase inhibitory activity — the same mushroom previously defined as “the strongest of 19.” The difference was the solvent and the fraction, not the mushroom. A commercial extract, ours or any other maker’s, is not the trial extract, and whoever writes “reishi clinically proven for the prostate” on a bottle is attributing to his bottle a trial that was done on something else. What actually was measured in our bottle, and about what exactly — in the product chapter below.

5-alpha-reductase and DHT: what was found in the test tube and in rats — and what does it prove about a man?

In the dish, triterpenoids from reishi inhibit the enzyme that turns testosterone into DHT: ganoderic acid DM with an IC₅₀ of 10.6 micromolar, in rat liver microsomes. In castrated rats given testosterone, reishi extract restrained prostate growth. And in men who took the extract for 12 weeks — blood testosterone did not change, and DHT was never measured in any human trial.

The mechanism all the marketing rests on is real — in the dish. In 2005, methanol extracts of 19 edible and medicinal mushrooms were screened, and reishi showed the strongest inhibition; the fruiting body or its extract inhibited testosterone-induced growth of the prostate in castrated rats. In 2006, ganoderic acid DM (IC₅₀ 10.6 micromolar) and a second lanostane compound (41.9 micromolar) were isolated from the extract — in rat liver microsomes, not in a whole animal. In 2012, in rats given testosterone at 3 mg/kg for 28 days, reishi extracts at 10, 20 and 50 mg/kg restrained the rise in prostate weight ratio, against finasteride at 1 mg/kg as the positive control, and PSA fell — in rats. And in 2026, a screen of 85 triterpenoids from four strains found in-vitro inhibition rates of 61.16% for ganoderic acid DM.

Now connect that to men. If the enzyme inhibition were translated into a hormonal signal in the body, something would have moved in the blood — testosterone, PSA, prostate volume. In both trials, including the 60 mg a day arm, nothing moved. The claim “reishi blocks DHT” is based on a measurement in rat liver microsomes; its most common source online is a review of plant-derived anti-androgens that names no dose, no test system and no endpoint, and cites a review. DHT in men after reishi has never been measured.

Does reishi change PSA — or could it mask prostate cancer?

There is no evidence of that. In both randomized trials PSA did not change — even though the extract was chosen for its 5-alpha-reductase inhibition, and even at a dose of up to 60 mg. The masking is documented for drugs: 5-alpha-reductase inhibitors lower PSA for up to 48 months from the start of treatment. With reishi there is no screen — and precisely because the question gets asked, there is no substitute for monitoring.

Medically, this is the most important question on the page, because lower urinary tract symptoms in a man over 50 can be benign enlargement — and can be something else. The justified fear is that a supplement will “lower PSA” and delay a diagnosis. What is known about the drugs: under finasteride or dutasteride the PSA reduction lasts up to 48 months, any rise from the nadir should be regarded as suspicious, and a biopsy decision that relies on PSA alone may miss aggressive tumors. What is known about reishi: PSA did not move in men with prostate symptoms, and it did not move either in 15 men with recurrent prostate cancer who took reishi for six months in an open-label study — zero partial responses, and zero as well in 32 men who took agaricus in the same study. Two opposite conclusions, both correct: there is no evidence that reishi masks PSA, and there is no evidence that it does anything hormonal at all. A review of randomized trials on diet, supplements and PSA — medicinal mushrooms among them — concluded that the evidence is “insufficient to recommend use.” The practical conclusion: a supplement is no reason to postpone a test, and no reason to cancel one.

Prostate cancer — what is there in the dish, and what is there in humans?

In humans: zero randomized trials, for any mushroom — the direct search returns zero. What exists is uncontrolled open-label studies, and three of them are negative: reishi (15 men), agaricus (32) and shiitake (62) — zero PSA responses. In the dish, extracts of reishi, lion’s mane, turkey tail and maitake damage prostate cancer cells. Cells in a dish are not a patient.

Start with the human. A shiitake extract was tested in 62 men with proven prostate cancer and rising PSA, three times a day for six months: by month 6 — 23 with disease progression, 0 complete responses, 0 partial, 4 with stable disease. The authors’ conclusion, in their words: “shiitake extract alone is not effective in the treatment of clinical prostate cancer.” The Cochrane review of reishi in cancer found only five randomized trials — none in prostate cancer, none with survival data — and concluded that there is insufficient evidence to justify using reishi as a first-line treatment. The only “positive” trial is a phase I study in 36 men with white button mushroom powder, 8–14 grams a day, with no control arm — a PSA response in 11%. A mushroom we do not sell, in a quantity that is not a capsule, without placebo.

And in the dish: reishi extract in LNCaP cells induced apoptosis and competed with DHT for the androgen receptor; lion’s mane extract suppressed the PI3K/AKT and RAS/MAPK pathways in prostate cancer cells — zero animals, zero humans; turkey tail extract lowered secreted PSA in one cell line, acted weakly in two, and did not act at all in a fourth; maitake beta-glucan enhanced the cytotoxicity of a chemotherapy drug in PC-3 cells. A 2022 review summed up the gap: of about 32 mushroom species that showed a signal in the test tube or in an animal, only 11 have ever been tested clinically, and most of the trials are small. ⛔ We are not hinting at prevention and not at treatment. Anyone facing prostate cancer — the address is the oncologist, and we wrote about mushrooms and cancer research separately.

What is PC-SPES — and why is it still cited as “evidence for reishi”?

PC-SPES was a mixture of eight herbs, reishi among them, sold to prostate cancer patients, which lowered PSA in case reports and surveys. The FDA took it off the shelves, and its MeSH record carries the term “drug contamination.” And when the mixture was broken down into its components in cells — reishi was among the herbs that actually raised PSA expression.

This is a complete myth chain, and it is worth knowing because it comes back in every discussion of mushrooms and the prostate. In 2000, two cases of hormone-refractory prostate cancer were reported in which PSA fell from 100 and from 386 ng/mL to 24 and to 114 under PC-SPES; a survey of a support group reported that 88% of users kept their PSA low. A mixture of eight herbs, uncontrolled, unblinded — and not one number attributable to reishi. Then two things happened. First: in 2002, each herb was tested separately on LNCaP cells; reishi suppressed growth by 63.5%, but of the eight herbs only licorice, skullcap and saw palmetto lowered PSA — “the other herbs actually increased PSA expression,” reishi among the “others.” Second: the product was recalled from the shelves by the US FDA, and the literature files it under “drug contamination.” The lesson: a supplement that seemed to “work” on PSA may have worked because it contained something else entirely, and PSA data from mixtures are not evidence for a mushroom. The same pattern in the reviews: a review of prostate treatments lists reishi among plants with “some improvement” — and concludes that for lack of evidence, botanical treatments earn no advantage and alpha-blockers will remain the urologists’ choice. The list is a list of the mentioned, not the proven.

Sexual function, testosterone and fertility — what was measured in humans?

Nothing. There is not a single trial in the world that measured erectile function in a human being after any mushroom, and no trial in men that measured sperm quality after cordyceps. “Cordyceps raises testosterone” was measured in mouse Leydig cells; “reishi improves erections” — in diabetic rats. The nickname “Himalayan Viagra” appears as a keyword in a paper titled “Myths and Realities.”

The search for mushrooms and erectile function returns nine publications, and zero trials in humans: a reishi polysaccharide in rats with diabetes-induced erectile dysfunction (100 or 400 mg/kg, 8 weeks) improved erectile tests and raised testosterone — in rats; cordyceps in diabetic rats versus sildenafil — rats; chaga extracts in rat penile smooth muscle cells, in which one extraction method actually raised PDE5, the enzyme that ends an erection. The most important paper in this chapter is a 2017 position paper in Trends in Biotechnology on “the mysterious caterpillar fungus,” which describes its marketing for male impotence under the heading “myths and realities.” And what every testosterone claim rests on: a 2003 study in which cordyceps fractions stimulated testosterone production in purified mouse Leydig cells, and in live mice. Mice.

Fertility: cordycepin, the compound, improved hyperactivated motility of human sperm — in a dish, not in a man and not in a pregnancy. Lion’s mane mycelium improved sperm count in rats exposed to microplastics — and that is the entire evidence in the world on lion’s mane and men’s health. And the most honest finding in the chapter: reishi polysaccharides and triterpenoids in obese rats improved sperm motility and restored testosterone — and “pregnancy rates did not change significantly.” The hardest endpoint did not move. More on cordyceps and sexual function and on mushrooms and hormonal balance — on the dedicated pages.

I take tamsulosin or finasteride — can I add a mushroom?

That is a question for your doctor, and what matters to know before the conversation: there is not one study in all of PubMed on an interaction between medicinal mushrooms and tamsulosin, finasteride or dutasteride — the search returns zero. The safety base in men with prostate symptoms is 138 men, up to 12 weeks, with no drug alongside. Absence of evidence of harm is not evidence of absence of harm.

What is known: in both trials “treatment was well tolerated with no serious adverse effects” — 138 men, up to 60 mg a day, up to 12 weeks. A systematic review of 34 randomized trials of fungal beta-glucans, at doses of 2.5 to 1,000 mg a day for up to 6.5 months, recorded no adverse event causally linked to the glucans — but it did not review the prostate, PSA or prostate drugs. The Cochrane review of reishi in cancer recorded nausea and insomnia, with no significant hematological or hepatic toxicity. What does not exist: safety data for a year, for two years, or in combination with an alpha-blocker or a 5-alpha-reductase inhibitor — that is, exactly the situation of most of the men who arrive at this page. And one more thing a man at this age has to know: reishi has a measurable effect on blood platelets in humans, so anyone taking aspirin or an anticoagulant — we set it out on the blood pressure page and on who shouldn’t take reishi. The rule: not instead of the medication, not without the doctor. The full list — in drug interactions.

Same extract, same enzyme — and why does it matter for hair too?

Because the same mechanism is sold twice. 5-alpha-reductase produces the DHT involved both in prostate enlargement and in hereditary hair loss, so the same 2005 study is cited both as “reishi for the prostate” and as “reishi for hair loss.” The difference: for the prostate there are two trials in men, in which the hormones did not move. For hair — zero trials.

This is a real connection between two pages, not just a link. The strongest evidence on reishi and hair is precisely the two prostate trials you have just read: the same extract, the same enzyme inhibition in the dish, and in men — testosterone and PSA unchanged. If the hormonal signal did not reach the blood, there is no reason to assume it reaches the hair follicle. Whoever cites 2005 and omits the human trials is omitting the part that contradicts him. The other side of the story, including the famous mouse trial that was done on an entirely different plant, we wrote up in medicinal mushrooms and hair loss. And the complete picture of what was and was not measured on reishi, condition by condition — in the reishi evidence ledger. In the same series: cordyceps and lung health and kidney health.

What has never been tested at all?

5 queries returned zero results across all of PubMed: any medicinal mushroom with chronic prostatitis or pelvic pain; lion’s mane, turkey tail or cordyceps with prostate enlargement; any mushroom in prostate cancer in a randomized trial; mushrooms with tamsulosin, finasteride or dutasteride; and cordyceps with sperm quality in men. Here, evidence of absence is evidence.

Evidence of absence is evidence when the search is systematic. There is not one publication in the world, at any grade of evidence, linking a medicinal mushroom to chronic prostatitis — no trial, no case report, not even cells in culture. Lion’s mane, turkey tail and cordyceps have never been tested for prostate enlargement, in any animal. Nocturia and frequency: three publications, and zero measurement in a man — what there is are isolated rat bladder strips, in which a cordyceps extract caused a contraction followed by relaxation, and a bladder ischemia model in a rabbit. And a review proposing that lion’s mane may affect the urinary tract via the gut — a hypothesis, without a single patient. You will also find the sources by mushroom in the research hub — reishi.

What we actually measure in our bottle

After a page about a research extract that is not ours, you deserve to know what was measured in ours — and about what. We grow the mushrooms ourselves, on a farm in the Galilee: fresh fruiting body, not mycelium grown on grain and not an imported powder whose name on the sack cannot be verified. The mushroom goes from harvest straight into extraction, with no drying step in between; as far as we know, we are among the few in the world who work this way. The extraction is triple, and its alcohol stage lasts 7 weeks. The extraction ratios on a fresh-mushroom basis: reishi 1:3 and cordyceps 1:2.5. Alcohol in the finished extract: 32%.

And the numbers are not ours to set. We sent the finished extracts to be tested at TÜV Austria, and what came back is the beta-glucan percentage on a dry-matter basis — and beside it alpha-glucan, that is, starch, which was not detected in any of them. Alpha-glucan that is not detected is the chemical proof that there is no grain in the bottle. To understand why that matters, it helps to know the market’s three-step ladder: mycelium grown on grain, in which beta-glucan is usually below 7% and most of the weight is the grain’s starch; imported dried fruiting body, whose quality depends on who dried it and when; and fresh fruiting body from the farm, which is what we do. Why beta-glucan and not “total polysaccharides” — we explained separately.

Extract	Beta-glucan (dry basis)	Alpha-glucan (starch)
Cordyceps	28.16%	Not detected
Reishi	25.65%	Not detected
Lion’s mane	23.93%	Not detected
Turkey tail + reishi	23.21%	Not detected

All our tests are public, and anyone who wants to read the report for themselves will find our guide to reading a COA. Kosher certification — Mateh Yehuda Rabbinate, Rabbi Gad Atias. That is what we know how to measure and prove about what is in the bottle. What it will do for your prostate or your urinary symptoms was not measured in this bottle — so it is not written.

What this page does not say — and what we do not claim

We do not claim that reishi, cordyceps, lion’s mane or turkey tail treat prostate enlargement, shrink it, improve urine flow, lower PSA or protect against prostate cancer. We do not claim that our extract is the extract tested in the trials — it is not. We do not claim that an improvement of 1.18 points on a questionnaire is an improvement you will feel — the measurement says most men will not. We do not claim that enzyme inhibition in a dish is a clinical achievement; in men, the hormones did not move. And we do not claim the opposite either — there is no evidence that reishi harms the prostate or masks PSA. What we do say: lower urinary tract symptoms in a man over 50 require evaluation by a doctor, before any supplement and not instead of one, and anyone already taking a prostate medication talks to the doctor before adding anything, including ours. We sell mushroom extracts, and we are telling you explicitly not to buy them for your prostate.

Dealing with prostate symptoms, or under PSA surveillance? The first address is your family doctor or urologist — for evaluation before, not instead. Before any supplement, including ours, talk to your doctor, especially if you take tamsulosin, finasteride, dutasteride, aspirin or an anticoagulant. A mushroom extract is a dietary supplement, not a treatment. Our matching quiz is built to choose a mushroom by goal — sleep, focus, endurance, immunity — and not by medical condition, and the prostate is not one of the goals in it. 100-day trial, free shipping over ₪285. Take the matching quiz See the lab results

The bottom line

Reishi is the only mushroom that has been tested in men with prostate symptoms, and what was measured is an improvement of 1.18 points on a questionnaire versus placebo — below the 3-point threshold that defines a clinical responder, and below the 5.26 that men report as a noticeable improvement — while urine flow, prostate volume, PSA and testosterone did not move. The extract that was tested is not the extract that is sold, including ours. Prostate cancer: zero randomized trials, and three negative open-label studies. Sexual function: zero measurements in a human being. Interaction with prostate medications: zero studies. Anyone with symptoms — to the doctor, before and not instead. And if someone is selling you a mushroom for your prostate, send them this page.

Frequently asked questions

Does reishi help with prostate symptoms?