Functional mushrooms, what the research says about lion's mane, reishi and more
Lion's mane, reishi, chaga, cordyceps and turkey tail compared by their trials in people, with safety points and what to check on a label.
- Written by
- Liz W.
- Last updated
- Reading time
- 8 min read
Overview
Functional mushrooms are mushrooms such as lion's mane, reishi, cordyceps, chaga and turkey tail, taken as supplements. Lion's mane and cordyceps have small trials in healthy adults with mixed results. Reishi has a few small trials, turkey tail was tested mostly alongside cancer treatment, and we found no trials of chaga in people.
Key points
- Functional mushrooms are fungi such as lion's mane, reishi, chaga, cordyceps and turkey tail, sold as powders, capsules and coffees.
- Lion's mane has the most trials we found in healthy adults, and those trials are small with mixed results.
- Reishi has small trials with mixed results, including better fitness scores in one student trial and no effect on blood sugar in a Cochrane review.
- Fruiting body and mycelium are different parts, and some mycelium products tested as mostly grain.
- Reishi powder and large amounts of chaga have case reports of liver and kidney harm, so check first if you have either condition.
Reishi has been taken in Asia for more than 2,000 years [1]. Today it sits on UK shelves beside lion's mane, chaga, cordyceps and turkey tail, as capsules, powders, gummies and coffees.
Functional mushrooms are mushrooms taken as supplements for effects beyond everyday nutrition. Lion's mane and cordyceps have small trials in healthy adults with mixed results. Reishi has a few small trials with mixed results, turkey tail has been tested mostly alongside cancer treatment, and we found no trials of chaga in people.
What are functional mushrooms?
The name covers a handful of fungi sold for focus, energy, calm or immunity. They're usually dried and powdered, or made into an extract, rather than eaten as food. The five you'll see most often are lion's mane, reishi, chaga, cordyceps and turkey tail.
Which mushroom supplements have the most research?
Of these five, lion's mane has the most trials we found in healthy adults, with cordyceps and reishi next, and all of them are small. Here's how the five compare.
| Mushroom | Sold for | What trials in people found | Evidence |
|---|---|---|---|
| Lion's mane | Memory and focus | Small trials found improvements on some memory and thinking tests and not others [2] | Early |
| Cordyceps | Energy and exercise | Two of three trials in athletes found better endurance, one found no change [3] | Mixed |
| Reishi | Calm and immunity | Better fitness test results in one student trial, changes in immune cell tests in older women, no effect on blood sugar in type 2 diabetes [1][4][5] | Early |
| Turkey tail | Immune support | Tested alongside cancer treatment, with very low certainty results [6] | Early |
| Chaga | Antioxidants | We found no trial in people | None found |
Our guide to cordyceps covers its exercise trials.
Lion's mane
A 2025 review of lion's mane trials found small studies in people with and without memory problems. Results were mixed, with improvements on some memory and thinking tests and not others [2]. Our page of lion's mane studies lists each trial in people, with its dose and length.
Our guide to lion's mane covers the mushroom in more depth.
What is reishi mushroom good for?
Reishi has a handful of small trials in people, with different results by group. In a 2024 trial of 78 inactive female students in India, those taking 1,000 mg of reishi a day for 30 days did better on fitness tests than those on a placebo, and their anxiety and well-being scores improved [4]. In 39 older women, 2 g a day of reishi extract for 8 weeks changed several lab measures of how immune cells behave [5].
A Cochrane review found five trials, mostly in people with type 2 diabetes, taking 1.4 to 3 g a day for 12 to 16 weeks. Reishi didn't lower blood sugar, blood pressure or cholesterol compared with a placebo [1].
In a small safety trial, 16 healthy adults took 2 g of reishi extract or a placebo twice a day for 10 days, and the extract caused no side effects compared with the placebo [7].
Chaga and turkey tail
Chaga isn't a cap and stem at all. It grows as a dark, crusty lump on birch trees [8]. Most chaga research is in cells and animals, and we found no trial of it in people.
Turkey tail has been tested mostly as an extract given alongside cancer treatment. A Cochrane review of 7 trials in people with bowel cancer rated the evidence as very low certainty [6]. We found no trial of turkey tail in healthy adults.
Fruiting body or mycelium?
The fruiting body is the part you'd see above ground or on a tree. The mycelium is the network of root-like threads. Many supplements use mycelium grown on grain such as oats or rice, and lab tests of some of these found they were mostly grain, with little of the mushroom's own fibre [9].
So the part matters as much as the species. A label should say which one you're getting.
Are mushroom supplements safe?
Most trials report few side effects, but the risks differ by mushroom.
- Lion's mane. Trials reported mild stomach complaints, and it hasn't been linked to liver injury [10].
- Reishi. Rare case reports describe serious liver injury, including one death, after people switched to reishi powder [11].
- Chaga. It's high in oxalate, and case reports describe kidney damage after large amounts for months, such as 4 to 5 teaspoons a day for 6 months [12].
How to choose a mushroom supplement
Check the label for four things.
- The species. Each mushroom by its Latin name, such as Hericium erinaceus for lion's mane.
- The part. Fruiting body, mycelium, or mycelium grown on grain [9].
- The amount. The weight of each mushroom in a day's dose, not just a blend total.
- The evidence. Whether the mushroom has trials in people for what you want it for, using the table above.
Mushroom coffees blend several of these with caffeine. Our guide to mushroom coffee covers them.
Where Nooroots fits
Nooroots Ashwagandha + Lion's Mane pairs lion's mane fruiting body extract with KSM-66 ashwagandha root extract in two capsules a day. It's made for calm focus and calm resilience on demanding days.
Frequently asked questions
What are the best mushroom supplements?
Lion's mane has the most trials we found in healthy adults, followed by cordyceps and reishi, and all are small with mixed results [2][3][4]. We found no trials of chaga in people.
What are adaptogenic mushrooms?
Adaptogenic mushrooms is a marketing name for mushrooms such as reishi, cordyceps and chaga, sold to help the body cope with stress. Cordyceps and reishi both have small trials in healthy adults, mainly on exercise and fitness [3][4].
Is reishi good for sleep?
We found no trial of reishi for sleep in healthy adults. Its main review covered blood sugar, blood pressure and cholesterol, and found no clear effect [1].
What is turkey tail mushroom good for?
Turkey tail extracts have mostly been tested alongside cancer treatment, where a Cochrane review rated the evidence very low certainty [6]. We found no trials in healthy adults.
Is chaga safe?
Chaga is high in oxalate, and case reports describe kidney damage after large amounts taken for months [12]. People with kidney problems should speak to a GP first.
Can you take mushroom supplements every day?
Lion's mane trials gave it daily for up to several months, with mild side effects [2][10]. There's little research on taking several mushrooms together.
References
Every study here is listed so you can read it yourself. This guide is for general information and doesn't replace advice from your GP or pharmacist. We check it again at least every six months.
- Klupp NL, Chang D, Hawke F, et al. (2015). Ganoderma lucidum mushroom for the treatment of cardiovascular risk factors. Cochrane Database of Systematic Reviews 2: CD007259. PMID 25686270
- Menon A, Jalal A, Arshad Z, Nawaz FA, Kashyap R (2025). Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review. Frontiers in Nutrition 12: 1641246. PMID 40959699
- Shu MY, Zhang XC, Zuo L, et al. (2025). Effects of fungal supplementation on endurance, immune function, and hematological profiles in adult athletes: a systematic review and meta-analysis. Frontiers in Nutrition 12: 1670416. PMID 41280379
- Mitra S, Mitra M, Nandi DK, et al. (2024). Efficacy of lingzhi or reishi medicinal mushroom Ganoderma lucidum (Agaricomycetes) supplementation on psychological stress and selective fitness profile parameters in female college students in West Bengal, India. International Journal of Medicinal Mushrooms 26(11): 51–64. PMID 39241163
- Iser-Bem PN, Lobato TB, Alecrim-Zeza AL, et al. (2024). Ganoderma lucidum dry extract supplementation modulates T lymphocyte function in older women. British Journal of Nutrition 132(2): 130–140. PMID 38800991
- Pilkington K, Wieland LS, Teng L, et al. (2022). Coriolus (Trametes) versicolor mushroom to reduce adverse effects from chemotherapy or radiotherapy in people with colorectal cancer. Cochrane Database of Systematic Reviews 11: CD012053. PMID 36445793
- Wicks SM, Tong R, Wang CZ, et al. (2007). Safety and tolerability of Ganoderma lucidum in healthy subjects: a double-blind randomized placebo-controlled trial. American Journal of Chinese Medicine 35(3): 407–414. PMID 17597499
- Raal A, Kaldmäe H, Kütt K, et al. (2024). Chemical content and cytotoxic activity on various cancer cell lines of chaga (Inonotus obliquus) growing on Betula pendula and Betula pubescens. Pharmaceuticals 17(8): 1013. PMID 39204121
- Sweeney LC et al. (2026). Advances in enzymatic measurement of β-glucan in mushrooms, yeast, algae, and dietary supplements. Journal of AOAC International, published online 18 May 2026: qsag041. PMID 42152188
- LiverTox (updated 5 January 2024). Lion's mane. LiverTox: clinical and research information on drug-induced liver injury. US National Institute of Diabetes and Digestive and Kidney Diseases. PMID 38289992
- Wanmuang H, Leopairut J, Kositchaiwat C, et al. (2007). Fatal fulminant hepatitis associated with Ganoderma lucidum (Lingzhi) mushroom powder. Journal of the Medical Association of Thailand 90(1): 179–181. PMID 17621752
- Kikuchi Y, Seta K, Ogawa Y, et al. (2014). Chaga mushroom-induced oxalate nephropathy. Clinical Nephrology 81(6): 440–444. PMID 23149251
