Cordyceps, Lungs and Breathing: What the Research Actually Tested — and What It Hasn’t

Cordyceps, the caterpillar fungus of traditional Chinese medicine, is the mushroom every “supports breathing and oxygen use” claim rests on — and the only one of our four with human lung trials. The evidence exists only in COPD, all of it Chinese and almost all added to standard care; by the meta-analysis’s own account, no trial was placebo-controlled. Asthma: zero single-mushroom trials. And in the only trial of cordyceps alone, peak-exercise oxygen uptake did not change.

The kinds of evidence that do exist, from closest to a person to furthest: meta-analyses of Chinese cordyceps trials in COPD, with no placebo arm; two human trials in asthma — both of a multi-herb formula, one of them negative; four small exercise trials, most of them blends; one turkey tail trial in lung cancer that failed its primary endpoint; rats, mice and petri dishes. And on reishi — the mushroom we grow and sell — the only human respiratory evidence is that it is an allergen.

Do medicinal mushrooms help the lungs and breathing?

Not in any properly measured way. The only human evidence is cordyceps in COPD — Chinese trials with no placebo arm, almost always added to standard care. In asthma there is no single-mushroom trial. For oxygen use, cordyceps alone did not change peak-exercise oxygen uptake. And for reishi the opposite is documented: a respiratory allergen.

This page replaced an earlier version of ours that promised “support for breathing, oxygen use and lung function” without a single citation. Now there are 37 citations, and the picture is more complicated and less comfortable: there is real human evidence on cordyceps in COPD, and good reason not to rely on it yet; there are two asthma trials, and one of them lost to placebo; and there is one unambiguous human finding on reishi — in the direction of allergy, not benefit. We sell both cordyceps and reishi, and that is exactly why we write all of this. The page walks through COPD, asthma, oxygen, allergy, infections, lung cancer, myths and safety — and ends with what was actually measured in the bottle.

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

The table sorts eight mushrooms along five respiratory axes and along the other side — the mushroom as a cause of respiratory disease. Only one row contains randomized human trials in a lung disease: cordyceps, and without placebo. And only two rows contain human evidence of the mushroom itself as a trigger of allergy or lung disease: reishi and shiitake.

What did the cordyceps trials in COPD actually show?

A reported improvement — on a foundation that has no floor yet. The comprehensive meta-analysis pooled 15 studies in 1,238 COPD patients at GOLD stages 2–3 and found possible benefit in lung function and endurance; then the authors wrote: “no study was placebo-controlled or of high methodological quality”. The first placebo-controlled trial, in 160 participants, is still a protocol.

This is the chapter that decides whether the page is honest, so here is the structure of the evidence. A meta-analysis of 27 randomized trials of the Bailing capsule — a preparation made from cultured cordyceps mycelium — reported improvement in FEV1, in the FEV1/FVC ratio, in the 6-minute walk test and in exacerbations. But look at the design: in the treatment arm the preparation was given in addition to standard care, and in the control arm — standard care alone. It is always “drug + mushroom” versus “drug”, never mushroom versus placebo. A systematic review of 22 studies in 1,834 participants on Chinese herbal medicines added to COPD treatment found a 54.61-metre improvement in the walk test — but the principal herbs were astragalus, ginseng and cordyceps together, and the metres cannot be credited to the mushroom.

The largest modern trial, from 2025, teaches the most: 240 COPD patients were assigned to the Yong Chong Cao capsule versus the Bailing capsule — two cordyceps preparations with similar constituents — for 24 weeks plus 24 weeks of follow-up. The primary endpoint, the number of exacerbations, favoured the tested preparation (P=0.002). And in the same breath: “no significant differences were observed between the groups in lung-function parameters”, nor in the mMRC, CAT and CCQ questionnaires. There is no placebo arm here at all — a cordyceps preparation against a cordyceps preparation. And what closes the chapter: the protocol for the first placebo-controlled trial, 160 patients, 24 weeks, FEV1 as the endpoint — whose authors themselves write that the earlier studies “were limited by the lack of placebo control”. It contains not one result. When it is published, we will update this page — in whichever direction it points.

And what is cited as if it were done in humans — but was done in rats and on a computer?

Most of the “cordyceps and lungs” literature is rodents, cells and simulations. The most-cited study on “reversing airway changes” gave rats 2.5 to 7.5 grams per kg per day — in a 70 kg adult that is 175 to 525 grams a day. And “network pharmacology” studies are done on a computer alone, with no animal and no cell.

Three patterns are worth knowing, because they recur on every marketing page. The first: the impossible dose. In rats with COPD, cordyceps powder at 2.5, 5 or 7.5 grams per kg per day for 12 weeks reduced airway-wall thickening, collagen deposition and fibrosis. A real finding — at a dose with no equivalent in any capsule. The second: the isolated compound. Ergosterol, a single molecule, reversed cigarette-smoke damage in bronchial epithelial cells and in mice through NF-κB inhibition — a molecule at a laboratory dose, not a swallowed extract. The third: the computer. A 2025 “network pharmacology” study identified possible targets of cordyceps in COPD — PARP1, PDE4, HMOX1 — through databases and literature. It contains no biological experiment at all, not in an animal and not in a cell. It is the kind of publication that is cited the most and proves the least. More on what has and has not been measured for this mushroom is on the cordyceps science page.

Do cordyceps or reishi help asthma?

Not in any way that lets anyone say. There is no randomized trial of reishi, lion’s mane or turkey tail in asthma. The two cordyceps trials gave a multi-herb formula: the larger, in 85 children, failed — “the effect was smaller than the placebo effect”; the second measured blood markers only. In mice, reishi lowered inflammation but not airway reactivity.

The trial worth knowing is the one that failed, because it is the only one done properly: randomized, double-blind, placebo-controlled, 85 asthmatic children aged 7–15 on inhaled steroids, six months of a five-herb formula — astragalus, cordyceps, stemona, fritillaria and scutellaria — at 0.619 grams a day. The primary endpoint: reduction in steroid dose. The result: −2.3 mg on the formula versus −3.1 mg on placebo (P=0.915) — the placebo group came down further. FEV1/FVC, peak expiratory flow, severity score, biochemical markers — no difference. The authors wrote that the effect “was smaller than the placebo effect” and recommended consulting a professional before preferring a herbal formula over conventional treatment. The second trial, in 60 adults with moderate asthma, measured blood markers only — IgE, IL-4, MMP-9 — not FEV1, not symptoms, not exacerbations; and its abstract confuses the treatment group with the control.

Reishi in asthma has been tested only in mice, and there the finding shows exactly where the line runs: in 40 mice sensitised with ovalbumin, reishi significantly lowered a row of inflammatory cytokines — and then the authors write that no significant change was observed in airway hyper-responsiveness, in goblet-cell hyperplasia, in mucus secretion, nor in IL-4 and IL-13, the two central cytokines of allergic asthma. Inflammation fell; the functional measure that defines asthma did not move. In a mouse. In humans — zero FEV1 measurements after reishi, ever. And worth knowing: the study of the Cs-4 preparation in mouse and rat models of rhinitis and asthma was written in part by authors affiliated with the company that markets it.

Does cordyceps improve oxygen use and lung function?

In the only trial that gave cordyceps alone — 12 young men, 1 gram of extract, a placebo-controlled crossover — resting oxygen uptake rose (0.37 versus 0.24 litres per minute; P=0.022) and peak-exercise oxygen uptake did not change at all (P=0.490). The “VO2max improvements” quoted online were measured in mushroom blends or combined with rhodiola, and one of them was entirely negative.

The boundary between “lung function” and “athletic performance” matters, and the athletic side — VO2max, strength, endurance, recovery — we wrote up in cordyceps and athletic performance. Here, only what concerns breathing. The cleanest trial, from 2026: cordyceps alone, 30 minutes before a cycling test to exhaustion. Resting oxygen uptake rose; at peak exercise — it did not. Reaction time in a Stroop test after exercise was faster (P=0.042), but the condition×time interaction was not significant. Glucose, blood pressure and heart rate — no difference. The authors’ own conclusion: an acute cognitive effect, independent of exercise — not a performance improvement.

The study everyone quotes is on a mushroom blend, not on cordyceps: 28 participants, 4 grams a day, versus maltodextrin. After one week — no significant interaction on any measure (VO2max P=0.364, time to exhaustion P=0.540). Only after 3 weeks, and only in the 10 volunteers who continued, did VO2max improve by 4.8 ml per kg per minute versus 0.9 on placebo (P=0.042). n=10, a blend, and a negative first week. The trial almost nobody cites: 8 cyclists, cordyceps with rhodiola, two exercise tests — no difference in muscle oxygen saturation, in VO2max, in ventilatory threshold or in time to exhaustion. And at 2,200 metres of altitude, 18 men on 1,400 mg of rhodiola and 600 mg of cordyceps a day: running time to exhaustion lengthened more (+5.7% versus +2.2%) — with 9 per arm, two ingredients, and erythropoietin that stayed higher in the placebo group of all places. And if you have seen “cordyceps and chaga reduced inflammation after cycling” — the supplement in that trial included beetroot nitrate, caffeine, vitamin C and B vitamins, and only at the end 2.5 grams of a mushroom blend; the authors attributed the result to the beetroot.

Reishi is a documented respiratory allergen — and we grow it

Yes. In a two-year study in Delhi, 28.48% of 172 respiratory-allergy patients showed a marked skin reaction to reishi spore extract, and 17.44% to the fruiting-body extract; more than 80% of the positives had significantly elevated IgE. Peak airborne spores: 336 per cubic metre in September. This is IgE-mediated allergy — not “mushroom worker’s lung”, which is not documented for reishi.

This is the chapter that turns the page from an advertisement into an asset, so it gets its full space. Reishi releases spores, and airborne spores are a documented allergen: the Delhi sampling ran from October 1989 to September 1991, the peak season is July–September, and sensitisation to the mushroom had been reported earlier in New Zealand, North America and Europe. Modern aerobiological monitoring in Poland found the spore season stronger in the countryside than in the city, and the authors open by noting that the high-concentration periods are periods when “allergy and asthma symptoms may appear in allergic individuals”. What this means for anyone sensitive to mould and fungi: reishi is not “safe because it is a mushroom”. Seasonal allergy and rhinitis — a different topic with a close connection — we covered in reishi and seasonal allergies.

And the distinction that must not be blurred: IgE allergy is not “mushroom worker’s lung” — hypersensitivity pneumonitis. The search linking reishi to hypersensitivity pneumonitis or to growers’ occupational asthma returns zero results. That disease is documented for shiitake: a 37-year-old French grower with a month of dry cough and shortness of breath, arterial oxygen 65 mmHg, 55% lymphocytes in the bronchoalveolar lavage fluid, and precipitins to shiitake spores — who recovered completely after the exposure stopped, with the authors warning that the growing interest in exotic mushrooms “may increase the risk” among mushroom workers. And a first European case of occupational asthma from shiitake, with distinct allergen bands at 15 and 24 kilodaltons. The broader background: inhaled beta-glucan is an airway irritant — in 42 poultry-house workers exposed to organic dust, airway reactivity was significantly higher than in 40 controls. Inhaled. Swallowed — a different story, and a different question.

Do medicinal mushrooms protect against colds and respiratory infections?

Not measured once. No trial in the common cold or seasonal respiratory infection exists with any of our four mushrooms — the search returns zero. The closest trial measured antibody titres after a flu vaccine in 30 adults. In blood cells from older adults, extracts of a close relative of lion’s mane and of turkey tail lowered interferon against respiratory viruses.

The only trial that comes close: 30 healthy adults who received a seasonal flu vaccine, with the intervention group taking AHCC, an extract of shiitake mycelium, at 3 grams a day. Three weeks after vaccination, the antibody titre to influenza B improved significantly in the supplement group. The endpoint: antibodies — not colds, not illness duration, not days off work; 30 participants, a pilot. And from the other side, a finding that demands caution and that most sites will not tell you about: peripheral blood cells from older adults were treated with extracts of Hericium coralloides — a close relative of lion’s mane from the same genus — and of turkey tail, and then exposed to rhinovirus and influenza. In the presence of virus, type I and type II interferon fell significantly with every extract at at least one concentration, and IL-1β, IL-6 and IL-8 rose. Interferon is the body’s antiviral defence. Cells in a dish, not people — but the direction is the opposite of “immune boosting against colds”, and we wrote about that distinction on the autoimmune disease page. And a 2021 review that asked in its title whether medicinal mushrooms might help against COVID-19 is a hypothesis resting on mice with sepsis — without a single human trial in lungs.

Turkey tail and lung cancer — what was measured, and what failed?

Two human trials. The larger, chemotherapy with or without PSK in 138 lung-adenocarcinoma patients: response 17.9% versus 16.9%, median survival 330 versus 331 days — zero difference. The smaller, 68 patients and 28 days of PSP: blood counts improved, but “patients did not improve in disease symptoms”. Turkey tail as an adjunct in lung cancer is not proven.

A sharp separation between systems, because here the confusion is the most dangerous. The larger trial, from 1990, compared cisplatin and vindesine against the same chemotherapy plus 3 grams of PSK a day: on the primary endpoint — zero difference. Only in the stage III subgroup was 11.1% versus 37.5% reported (P=0.046), with a median-survival difference that was not significant (P=0.075) — a subgroup search after a failed primary. The smaller trial, from 2003: 68 patients with advanced non-small-cell lung cancer who had completed conventional treatment, 34 per arm, 28 days. Leukocyte count, IgG, IgM and body-fat percentage improved; fewer patients withdrew because of disease progression (5.9% versus 23.5%; P=0.04). And then the authors’ decisive sentence: the patients did not improve in disease symptoms. The success is in a trial-withdrawal measure, over 28 days, in 68 patients.

And what gets quoted as “PSK and lungs” is actually about the colon: in 205 colorectal-cancer patients, PSK with oral chemotherapy reduced recurrence, “especially lung metastasis” (odds ratio 0.27) — prevention of metastases from a bowel tumour, not treatment of primary lung cancer and not a lung disease. And a 2025 review on combining reishi and turkey tail with EGFR inhibitors in lung cancer warns explicitly of a “potential risk of herb–drug interactions” through drug transporters and cytochrome P450 enzymes — and reports no clinical trial of the combination. Anyone facing lung cancer — the address is the oncologist, and mushrooms and cancer research we wrote separately.

And what about lion’s mane and turkey tail for breathing?

Nothing. There is not one publication with a respiratory endpoint for lion’s mane — not COPD, not asthma, not lung function. The search for lion’s mane or turkey tail with asthma, COPD or spirometry returns two publications, and neither is a respiratory study. Turkey tail has been tested in humans only as an adjunct in lung cancer — see the previous chapter.

It is worth knowing what does come back in the search, because any result may surface online as “a study on lion’s mane and lungs”: a publication on spinocerebellar ataxia, a study on blood cells in culture, and five publications on lion’s mane with “lung” or “asthma” of which not one measures breathing. The only finding that touches breathing is the one from the infections chapter — interferon falling in cells, in a close relative from the same genus — and it points the opposite way. If someone is selling you lion’s mane “for the lungs”, there is not one measurement behind it.

Where did “ATP by 28%” and “it grows at 4,000 metres, so it helps you breathe” come from?

From mice and from a story. The ATP claim comes from a study where a cordyceps preparation raised ATP in mouse brains after a stroke — not muscle, not a human, not exercise, no percentage in the abstract. The altitude claim rests on an anti-hypoxia study done on a computer, in rat heart cells, mice and a hen’s egg. Not one human.

The ATP myth: mice received a fermented cordyceps preparation at 0.04 to 1 mg per kg before cerebral-artery occlusion. Prolonged pre-treatment reduced infarct volume, and “the ATP concentration rose significantly in the ischaemic brain”. And in mice with a temporary occlusion — zero neuroprotection. From this was born “cordyceps increases ATP production by 28%”: brain, after a stroke, in a mouse, with no percentage. The altitude myth: an anti-hypoxia study combined network pharmacology, H9C2 cells (rat heart cells), mice, and a chorioallantoic-membrane model — a hen’s egg. The connection between the altitude at which the fungus grows in the wild and a person’s ability to breathe is not a finding; it is a story. And incidentally, the preparations studied in COPD are cultured mycelium — because, as a Chinese review notes, production of the wild fungus is “so limited that it cannot be used widely”.

And a third myth, which we of all people need to say out loud: “X% of the supplements on the market are fake”. No such number exists in the literature. What is documented, in a review from the Institute of Microbiology of the Chinese Academy of Sciences: false geographic labelling, substitution of wild fungus with cultivated, adulteration, adulteration in blends and “artificial enhancement” — by name, and without percentages. The gap between what is written on the jar and what is inside it is a documented problem, and no study has screened labels against contents. That is why the chapter on our bottle talks about testing, not about promises.

Safety and interactions: cyclosporine, anticoagulants and respiratory drugs

The only interaction measured in humans is with cyclosporine: in 202 kidney-transplant recipients, cordyceps at 1 gram three times a day significantly lowered blood levels of the drug in the 3 to 6 months after transplantation. Theophylline, prednisone and anticoagulants — zero interaction studies. And a 2026 case report: a 9-year-old with seizures after a multi-component mushroom supplement.

The transplant trial is the strongest evidence in the file for a real drug interaction: 93 patients received cordyceps on top of their immunosuppressive regimen versus 109 controls. Graft survival, creatinine and acute rejection — no significant difference; liver and kidney toxicity — lower in the treatment group. And then: cyclosporine doses in the treatment group were significantly lower in months 2–6, and whole-blood trough concentrations of the drug were significantly lower in months 3–6. The mushroom changed the drug level. Anyone taking an immunosuppressant who adds cordyceps without telling their doctor is changing their own treatment. And this is a mushroom with measurable immunosuppressive activity, not an “immune balancer”.

What has not been tested: cordyceps with theophylline — zero. Cordyceps with prednisone in asthma patients — zero. Reishi with warfarin and antiplatelet drugs in humans — zero, and reishi’s measurable effect on platelets we covered on the blood pressure page. In other words: whoever says “safe” and whoever says “dangerous” are both making it up; the correct wording is “not tested”, and that is what you tell your doctor. And for parents: a 2026 case report of a 9-year-old with well-controlled epilepsy who developed myoclonic seizures, hallucinations and altered consciousness after a dose increase of a multi-component mushroom supplement containing reishi and cordyceps — and recovered completely when it was stopped. More in medicinal mushrooms for children, in who shouldn’t take cordyceps and who shouldn’t take reishi, and in the full list of drug interactions.

What has never been tested at all?

15 queries returned zero results across all of PubMed. Among them: reishi as a cause of hypersensitivity pneumonitis; reishi in growers’ occupational asthma; cordyceps with theophylline; cordyceps as a steroid-sparing agent in asthma; a mushroom supplement in the common cold in a randomized trial; and even one study screening mushroom-supplement labels against their actual contents.

Evidence of absence is evidence when the search is systematic. Zero placebo-controlled trials of cordyceps in COPD — the first has only been registered. Zero randomized trials of reishi, lion’s mane or turkey tail in asthma. Zero FEV1 measurements after reishi in humans. Zero trials in the common cold with any of our four mushrooms. Zero publications on reishi as a cause of hypersensitivity pneumonitis — the distinction that separates allergy from lung disease. And zero studies that checked whether a mushroom supplement’s label matches what is inside it — not for beta-glucan, not for species identification, not for adulteration. The sources by mushroom are also in the research hub — cordyceps. In the same series: medicinal mushrooms and prostate health, and what has and has not been measured for reishi, condition by condition — in the reishi evidence ledger.

What we actually measure in our bottle

After a page that is all “not tested” and “not placebo-controlled”, you deserve to know what was measured — 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. Extraction ratios on a fresh-mushroom basis: cordyceps 1:2.5 and reishi 1:3. Alcohol in the finished extract: 32%.

And the numbers are not ours to set. The finished extracts were tested at TÜV Austria, and what came back is the beta-glucan percentage on a dry-matter basis — and alongside it alpha-glucan, meaning starch, which was not detected in any of them. Alpha-glucan 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, where 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. And on a page where a scientific review documents species substitution and adulteration in the cordyceps market, and no study has screened labels against contents — the only way to know what is in the bottle is an open test of the bottle. Why beta-glucan and not “total polysaccharides” — we explained separately.

All our tests are public, and anyone who wants to read the report 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 lungs or your breathing was not measured — so it is not written.

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

We do not claim that cordyceps, reishi, lion’s mane or turkey tail improve lung function, relieve asthma or COPD, increase oxygen use, prevent colds or help in lung cancer — at any dose and in any form. We do not claim that the Chinese COPD trials “proved” anything; their own meta-analysis says they have no placebo arm. We do not claim that the acute cognitive effect in the cordyceps trial is a respiratory improvement. And we do not claim the opposite either — there is no evidence that taking a mushroom extract by mouth harms the lungs; what is documented is allergy to airborne spores, and an interaction with cyclosporine. What we do say: anyone living with asthma or COPD needs a pulmonologist and treatment with evidence behind it, and anyone taking a respiratory drug or an immunosuppressant talks to their doctor before any supplement — including ours. We sell mushroom extracts, and we are telling you explicitly not to buy them for your lungs.

The bottom line

The only human evidence on medicinal mushrooms and the lungs is cordyceps in COPD — 15 studies, 1,238 participants, and not one of them placebo-controlled, in the meta-analysis’s own words; the first trial with a placebo has not yet run. In asthma, the formula that included cordyceps lost to placebo in 85 children, and for reishi, lion’s mane and turkey tail there is no trial. Cordyceps alone did not change peak-exercise oxygen uptake. Turkey tail in lung cancer failed its primary endpoint. What was measured in humans: reishi is a respiratory allergen, and cordyceps changes cyclosporine levels. If you have a lung disease — to the doctor, before and not instead. And if someone is selling you a mushroom for your lungs, send them this page.

Frequently asked questions

Scientific sources (peer-reviewed)

• Systematic review and meta-analysis of cordyceps in stable COPD, GOLD 2–3: 15 studies, 1,238 participants; possible benefit in lung function and endurance — and “no study was placebo-controlled or of high methodological quality” — Yu X, et al. Evidence-Based Complementary and Alternative Medicine, 2019. View on PubMed
• Meta-analysis of 27 randomized trials of the Bailing capsule (cultured mycelium) added to standard COPD care: improvement in FEV1, FEV1/FVC, the 6-minute walk and exacerbations — always “treatment + mushroom” versus “treatment” — Ma G, Jin Y. Pharmaceutical Biology, 2024. View on PubMed
• Multi-centre randomized active-controlled trial in 240 COPD patients: one cordyceps preparation versus another, 24 weeks. Fewer exacerbations (P=0.002) — and no difference in lung function, mMRC, CAT and CCQ. No placebo arm — Li S, et al. Journal of Evidence-Based Medicine, 2025. View on PubMed
• Systematic review of Chinese herbal medicines added to COPD treatment: 22 studies, 1,834 participants; +54.61 metres on the 6-minute walk. Principal herbs: astragalus, ginseng and cordyceps together — Chen X, et al. PLoS One, 2014. View on PubMed
• Protocol for the first placebo-controlled trial: 160 COPD patients, 24 weeks, FEV1 endpoint; the authors write that the earlier studies “were limited by the lack of placebo control”. No results — Lin S, et al. Frontiers in Pharmacology, 2026. View on PubMed
• COPD rats, cordyceps powder at 2.5, 5 or 7.5 grams per kg per day for 12 weeks: less wall thickening, collagen and fibrosis. In a 70 kg adult — 175–525 grams a day — Yang L, et al. Experimental and Therapeutic Medicine, 2018. View on PubMed
• Ergosterol — an isolated molecule — reversed cigarette-smoke damage in bronchial epithelial cells and in mice through NF-κB inhibition. A single compound at a laboratory dose — Sun X, et al. Clinical Science, 2019. View on PubMed
• Network pharmacology only: possible targets of cordyceps in COPD (PARP1, PDE4, HMOX1, MMP1) through databases. No biological experiment, not in an animal and not in a cell — Zang Z, et al. Immunity, Inflammation and Disease, 2025. View on PubMed
• Randomized double-blind placebo-controlled trial in 85 asthmatic children aged 7–15: a five-herb formula including cordyceps, 0.619 grams a day, 6 months. Steroid reduction −2.3 versus −3.1 mg on placebo (P=0.915); “the effect was smaller than the placebo effect” — Wong ELY, et al. Journal of Alternative and Complementary Medicine, 2009. View on PubMed
• 60 patients with moderate asthma, a cordyceps capsule added to an inhaled steroid, two months: falls in serum IgE, sICAM-1, IL-4 and MMP-9. Blood markers only — not FEV1, not symptoms — Wang NQ, et al. Zhongguo Zhong Yao Za Zhi, 2007. View on PubMed
• The Cs-4 preparation (cultured mycelium) in mouse and rat models of allergic rhinitis and asthma: falls in IgE and IL-4/IL-13. Rodents; two authors affiliated with the company that markets the preparation — Chen J, et al. Molecules, 2020. View on PubMed
• 40 asthmatic BALB/c mice: reishi lowered IL-1β, -5, -6, -8, -17, -25, -33 and -38 — and “no significant change was observed” in airway hyper-responsiveness, goblet-cell hyperplasia and mucus secretion; IL-4 and IL-13 unchanged — Li Y, et al. Respiratory Physiology & Neurobiology, 2022. View on PubMed
• An isolated chromatographic fraction of reishi (GLEF100) in asthmatic mice: falls in IgE and NF-κB. A fraction, not a commercial extract; mice — Li N, et al. Journal of Natural Medicines, 2026. View on PubMed
• Reishi polysaccharide in engineered particles for inhaled delivery: reached deep lung tissue in mice. A drug-delivery engineering study, inhaled — not swallowed, not efficacy — Xing Z, et al. European Journal of Pharmaceutical Sciences, 2018. View on PubMed
• Randomized double-blind placebo-controlled crossover trial in 12 young men: 1 gram of cordyceps extract alone before a cycling test. Resting VO2 0.37 versus 0.24 litres per minute (P=0.022); peak-exercise VO2 unchanged (P=0.490); faster Stroop (P=0.042) — Farzan H, Koushkie Jahromi M. PLoS One, 2026. View on PubMed
• 28 participants, a 4-gram-a-day mushroom blend versus maltodextrin: after one week — no significant interaction on any measure (VO2max P=0.364); after 3 weeks in 10 volunteers — +4.8 versus 0.9 ml per kg per minute (P=0.042) — Hirsch KR, et al. Journal of Dietary Supplements, 2017. View on PubMed
• 8 cyclists, a cordyceps-and-rhodiola formula, double-blind placebo-controlled: no difference in muscle oxygen saturation, VO2max, ventilatory threshold or time to exhaustion — Colson SN, et al. Journal of Strength and Conditioning Research, 2005. View on PubMed
• 18 men at 2,200 metres, rhodiola 1,400 mg + cordyceps 600 mg a day versus placebo (9 per arm): running time to exhaustion +5.7% versus +2.2%; erythropoietin higher in the placebo group of all places. A blend, controlled but not randomized — Chen CY, et al. High Altitude Medicine & Biology, 2014. View on PubMed
• 20 cyclists, a supplement of beetroot nitrate, caffeine, vitamin C, B vitamins — and 2.5 grams of a mushroom blend with cordyceps and chaga: the authors attributed the reduced inflammation to the beetroot nitrate. The mushrooms were not isolated — Nieman DC, et al. Frontiers in Nutrition, 2024. View on PubMed
• 172 respiratory-allergy patients in Delhi: 28.48% marked skin reaction to reishi spore extract and 17.44% to the fruiting body; more than 80% of the positives with significantly elevated IgE. Peak of 336 spores per cubic metre in September — Singh AB, et al. Clinical and Experimental Allergy, 1995. View on PubMed
• Aerobiological monitoring of reishi spores in Poland: the spore season is stronger in the countryside than in the city; high-concentration periods are periods of allergy and asthma symptoms in sensitised people — Wójcik-Kanach M, Kasprzyk I. Fungal Biology, 2025. View on PubMed
• Case report: a 37-year-old mushroom grower with hypersensitivity pneumonitis from shiitake spores — arterial oxygen 65 mmHg, 55% lymphocytes in BAL; full recovery after the exposure stopped — Ampere A, et al. Medical Mycology, 2012. View on PubMed
• Case report: severe hypersensitivity pneumonitis from shiitake spores with decreased pulmonary perfusion, treated with prednisolone — Murakami M, et al. Journal of Internal Medicine, 1997. View on PubMed
• IgE-mediated occupational asthma from shiitake: skin test positive to shiitake alone, allergen bands at 15 and 24 kilodaltons; the attacks stopped with avoidance — Pravettoni V, et al. International Journal of Occupational Medicine and Environmental Health, 2014. View on PubMed
• 42 poultry-house workers versus 40 controls: exposure to airborne endotoxin and beta-glucan — significantly higher airway reactivity. Inhaled beta-glucan is a respiratory irritant — Rylander R, Carvalheiro MF. International Archives of Occupational and Environmental Health, 2006. View on PubMed
• 30 healthy adults after a flu vaccine, AHCC 3 grams a day: the antibody titre to influenza B improved significantly. Endpoint: antibodies — not colds; a pilot — Roman BE, et al. Nutrition Research, 2013. View on PubMed
• Peripheral blood cells from older adults with extracts of Hericium coralloides and turkey tail, against rhinovirus and influenza: type I and type II interferon fell significantly, IL-1β, IL-6 and IL-8 rose. Cells in culture — Williams LM, et al. Nutrients, 2023. View on PubMed
• A hypothesis review: could medicinal mushrooms help against COVID-19? Rests on mice with sepsis; without a single human trial in lungs — Hetland G, et al. Scandinavian Journal of Immunology, 2021. View on PubMed
• Randomized double-blind placebo-controlled phase II trial in 68 patients with advanced non-small-cell lung cancer: PSP for 28 days. Blood counts and IgG/IgM improved; fewer withdrawals (5.9% versus 23.5%; P=0.04); “patients did not improve in disease symptoms” — Tsang KW, et al. Respiratory Medicine, 2003. View on PubMed
• Randomized controlled trial: chemotherapy versus chemotherapy + PSK 3 grams a day in lung adenocarcinoma, 138 cases — response 17.9% versus 16.9%, median survival 330 versus 331 days; the stage III subgroup not significant for survival (P=0.075) — Nishiwaki Y, et al. Gan To Kagaku Ryoho, 1990. View on PubMed
• 205 colorectal-cancer patients: PSK + oral chemotherapy reduced recurrence, “especially lung metastasis” (odds ratio 0.27). Colon — not primary lung cancer — Ohwada S, et al. British Journal of Cancer, 2004. View on PubMed
• Review on combining reishi and turkey tail with EGFR inhibitors in lung cancer: an explicit warning of a “potential risk of herb–drug interactions” through transporters and CYP450 enzymes; no clinical trial of the combination — Zhang H, et al. Pharmaceutics, 2025. View on PubMed
• 202 kidney-transplant recipients: cordyceps 1.0 gram three times a day (93) versus control (109). Cyclosporine doses significantly lower in months 2–6, and blood trough concentrations significantly lower in months 3–6. The only interaction measured in humans — Li Y, et al. Transplantation Proceedings, 2009. View on PubMed
• Case report: a 9-year-old with well-controlled epilepsy developed myoclonic seizures, hallucinations and altered consciousness after a dose increase of a multi-component mushroom supplement containing reishi and cordyceps; full recovery on stopping it — Melek Arsoy HE, Özdemir Ö. BMC Complementary Medicine and Therapies, 2026. View on PubMed
• Review of cordyceps products on the market: false geographic labelling, substitution of wild fungus with cultivated, adulteration, adulteration in blends and artificial enhancement — documented by name, without percentages — Meng G, et al. Critical Reviews in Biotechnology, 2025. View on PubMed
• The source of the ATP myth: a cordyceps preparation in mice before cerebral-artery occlusion — “the ATP concentration rose significantly in the ischaemic brain”; zero neuroprotection in temporary occlusion. Brain, stroke, mouse, no percentage — Wu J, et al. Biomedicine & Pharmacotherapy, 2020. View on PubMed
• Anti-hypoxia study of cordyceps: network pharmacology, rat heart cells, mice and a hen’s egg membrane. Not one human — the source of the “grows at altitude, so it helps you breathe” myth — Long H, et al. Journal of Ethnopharmacology, 2021. View on PubMed

Read next

• Medicinal mushrooms by goal — the hub
• The research hub — cordyceps
• Cordyceps science — what was measured and what was not
• Cordyceps and athletic performance
• Reishi and seasonal allergies
• Medicinal mushrooms and blood pressure
• Medicinal mushrooms and prostate health
• Medicinal mushrooms and autoimmune disease
• Mushrooms and cancer research
• Medicinal mushrooms for children
• Who shouldn’t take cordyceps?
• Who shouldn’t take reishi?
• Medicinal mushrooms and drug interactions
• Do medicinal mushrooms have side effects?
• Lab results — beta-glucan
• How to read a test report (COA)
• Fresh or dried mushrooms

The information on this page is for educational purposes only and does not constitute medical advice, diagnosis or a substitute for professional care. Medicinal mushroom extracts are dietary supplements, not drugs, and are not intended for the treatment of asthma, COPD, respiratory infections, lung cancer or any other medical condition. Lung diseases require medical follow-up and treatment; do not stop, replace or change the dose of any respiratory or immunosuppressive medication without your treating physician’s guidance. Before starting any supplement — and especially if you take steroids, theophylline, immunosuppressants or anticoagulants, have a known sensitivity to mould or fungi, are pregnant or breastfeeding, are giving it to a child, or have any existing medical condition — consult a physician. *These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.*