Lion's Mane: what it is and what the research says

Lion's Mane (Hericium erinaceus) is an edible mushroom that grows on oak, beech and other broadleaf hardwoods across Asia, Europe and North America, usually on dead or damaged trunks. It has no cap and no stem. It forms a rounded clump of soft white spines that hang down like icicles, and that shaggy look gives it its name. Older specimens turn cream, then yellowish brown.

It goes by plenty of other names. In Japan it is yamabushitake, after the mountain monks whose robes the spines were said to resemble. In China it is hou tou gu, the monkey head mushroom. English speakers also call it bearded tooth, hedgehog mushroom or pom pom mushroom.

A few related Hericium species grow in Europe and look similar, including coral tooth and tiered tooth. H. erinaceus is the one grown commercially and the one used in almost every study, so when a label says Lion's Mane, that is the species it should mean.

In Britain the wild mushroom is rare. It is listed on Schedule 8 of the Wildlife and Countryside Act 1981, the strongest legal protection given to plants and fungi, which makes picking it in the wild an offence. Everything you buy in the UK, fresh or as a supplement, comes from cultivated mushrooms grown on sawdust, logs or grain.

In China and Japan, Lion's Mane has been cooked as a food for generations and prepared as a tonic in traditional practice, often dried and simmered into soups and teas. Traditional Chinese sources describe it as a mushroom for the stomach, and it also appears in Korean and Indian traditional use. That is a description of how it was used, not evidence that it works.

You will sometimes read that the ancient Greek physician Hippocrates praised Lion's Mane around 450 BCE. We could not trace that claim to a primary source, so we treat it as a story that gets repeated rather than as history.

Scientific interest took off in the early 1990s, when Japanese chemists isolated two groups of compounds from the mushroom, hericenones and erinacines. Since then it has become one of the best known functional mushrooms in Europe and the US. It is sold in coffee blends, capsules, powders, tinctures and gummies, and it has more human research on memory and mood than any other mushroom we cover in our guides.

A mushroom has two main parts. The fruiting body is the bit you see and cook. The mycelium is the network of fine threads that grows through wood or soil. Both are used in supplements, and their chemistry is different.

• Hericenones are found mainly in the fruiting body.
• Erinacines are found mainly in the mycelium. Erinacine A is the one most often measured and the one used in a Taiwanese trial described below.
• Beta-glucans are long sugar chains found in the cell walls of most mushrooms. They are the compounds most often studied for effects on immune cells in the lab.
• Hericenone B slowed platelet clumping in laboratory work, which is one reason people on blood thinners are advised to check before taking Lion's Mane.

In cell studies, both hericenones and erinacines increased production of nerve growth factor (NGF), a protein that nerve cells need to grow and survive. That lab work is the reason Lion's Mane is often called the brain mushroom. Whether the same thing happens in a human brain at supplement doses has not been measured.

As a food, Lion's Mane is like most mushrooms: low in calories, fat and salt, with some protein and fibre. It contains B vitamins such as thiamine, riboflavin and niacin, and minerals including potassium, zinc and manganese. The amounts in a supplement serving are tiny, so a capsule or gummy should not be counted as a source of any of them.

At the time of writing (26 September 2026) there are only a handful of controlled human trials of Lion's Mane on its own. None had more than 80 people. Here is each one in plain terms, with who took part, what they took and what happened.

• Older adults with mild cognitive impairment, Japan, 2009. Thirty people aged 50 to 80 took either Lion's Mane tablets or a placebo for 16 weeks. The dose was four 250 mg tablets of dried fruiting body powder, three times a day, which is about 3 g daily. The Lion's Mane group scored higher on a cognitive function scale than the placebo group at weeks 8, 12 and 16. Four weeks after stopping, their scores fell back. Blood tests showed no adverse effects. The lead researcher worked for a mushroom company. Mori et al., Phytotherapy Research, 2009
• Older adults, Japan, 2019. A 12 week placebo-controlled trial of a fruiting body supplement. Scores on one screening test, the Mini Mental State Examination, were higher in the Lion's Mane group. Two other memory tests showed no difference. Saitsu et al., Biomedical Research, 2019
• People with mild Alzheimer's disease, Taiwan, 2020. A 49 week pilot trial using three 350 mg capsules a day of mycelium enriched with erinacine A. The placebo group's scores on one cognitive screening tool fell over the year, while the Lion's Mane group scored better on the Mini Mental State Examination and on everyday living tasks. Four people dropped out with stomach discomfort, nausea or a skin rash. The trial was run with the company that makes the ingredient. Li et al., Frontiers in Aging Neuroscience, 2020
• Healthy young adults, Northumbria University, UK, 2023. Forty-one people aged 18 to 45 took 1.8 g a day or a placebo for 28 days. After a single dose, the Lion's Mane group was faster on the Stroop task, a test of focus, 60 minutes later. After 28 days there was a trend towards lower stress scores that just missed statistical significance. Most other tests showed no difference, and a few went slightly the wrong way. Docherty et al., Nutrients, 2023
• Healthy young adults, University of Surrey, UK, 2025. Eighteen people aged 18 to 35 took one 3 g dose of a 10:1 fruiting body extract or a placebo. Ninety minutes later there was no overall difference in thinking or mood. One test of hand dexterity came out better in the Lion's Mane group. Surendran et al., Frontiers in Nutrition, 2025
• Women with menopausal and general health complaints, Japan, 2010. Thirty women ate cookies made with Lion's Mane powder or placebo cookies for four weeks. Depression scores and a general complaints score went down in the Lion's Mane group compared with where they started. Against placebo, concentration, irritability and anxiety moved in the same direction but did not reach significance. Nagano et al., Biomedical Research, 2010
• Adults with overweight or obesity, Italy, 2019. Seventy-seven people on a low calorie diet took a Lion's Mane supplement made from mycelium and fruiting body for eight weeks. Their questionnaire scores for depression, anxiety and poor sleep were lower afterwards. The diet itself makes the result harder to read. Vigna et al., Evidence-Based Complementary and Alternative Medicine, 2019

One more trial is often quoted. In 2016 a small study in people with ulcerative colitis used a mixed mushroom drink in which Lion's Mane was a minor ingredient. Symptom and quality of life scores were better than placebo after three weeks, but there was no difference for Crohn's disease, and nobody can say which mushroom was responsible.

Most headline claims about Lion's Mane come from cells in a dish or from mice and rats. That work shows how something might act, not what happens when a person eats a gummy.

• Nerves and the brain. Extracts encouraged nerve cells to grow in the lab and sped up nerve repair in rats after injury. In mouse models of Alzheimer's disease, they slowed memory loss and the build-up of amyloid plaques. Researchers have also looked at stroke, Parkinson's disease and multiple sclerosis in animal models.
• Mood. A 2018 mouse study reported fewer anxiety and depression-like behaviours, with signs of new cell growth in the hippocampus, a brain area involved in memory and emotion.
• Stomach. In rats, extracts protected the stomach lining against alcohol-induced ulcers, partly by thickening the protective mucus. In test tubes, they slowed the growth of Helicobacter pylori, the bacterium linked to many ulcers.
• Blood sugar. Diabetic rodents given Lion's Mane had lower blood sugar. One proposed reason is that it blocks alpha-glucosidase, an enzyme that breaks down carbohydrate in the gut. A six week mouse study also reported less nerve pain linked to diabetes.
• Fats and the heart. Mice on a high fat diet gained less weight and had lower triglycerides. Test tube work showed less oxidation of LDL cholesterol.
• Inflammation and the gut. Rodent studies reported lower markers of inflammation and oxidative stress, changes in gut bacteria and more activity in immune tissue lining the intestine. In one study, mice infected with a lethal dose of salmonella lived several times longer when given Lion's Mane.

Animal doses are often far higher, for body weight, than anything in a supplement.

What the evidence shows

• In small trials, people took between about 1 g and 3 g a day for anywhere from 4 to 49 weeks, and side effects were uncommon and mild.
• In older adults with mild cognitive impairment or early Alzheimer's disease, some cognitive screening scores were higher with Lion's Mane than with placebo.
• In healthy young adults, single doses gave mixed results: faster on one focus test in one study, no overall difference in another.
• In the one trial that followed people after they stopped, the difference faded within four weeks.

What it does not show

• That Lion's Mane prevents, treats or cures dementia, depression, anxiety or any other condition.
• That healthy people see lasting changes in memory or focus.
• What the right dose is, or whether fruiting body, mycelium or a particular extract works better.
• How it compares with a proper diet, sleep and exercise, which have far stronger evidence behind them.

There are good reasons for caution. Every trial was small. Several were funded or run by companies that sell Lion's Mane. Each used a different preparation, so the results cannot simply be pooled. Most took place in Japan and Taiwan, and few have been repeated by independent teams. The two UK trials, from Northumbria and Surrey, are among the more careful ones, and both reported modest or null findings alongside the positives.

That is why, in Great Britain, no health claim is authorised for Lion's Mane. It is also why we describe the studies rather than promise you a result.

Lion's Mane has a long history as a food, and the trials above reported few problems. They were short and small, though, so rare or long-term effects would not show up.

Side effects reported in trials and case reports include:

• Stomach discomfort, nausea and loose stools
• Skin rashes and itching
• Allergic reactions in people sensitive to mushrooms

One serious case was published in 2003. A 63 year old man in Japan developed acute respiratory distress syndrome, a severe lung reaction, after taking a Lion's Mane extract, and tests suggested a reaction to it. He recovered in hospital. Nakatsugawa et al., Internal Medicine, 2003 It is a single case, but it is the reason people with mushroom allergies or asthma are told to steer clear or ask first.

Check with your GP or pharmacist before taking Lion's Mane if you:

• are pregnant, trying to conceive or breastfeeding, since there is not enough safety information
• take medicine for diabetes, because animal studies found lower blood sugar
• take blood thinners or antiplatelet drugs such as warfarin, apixaban, clopidogrel or daily aspirin, because of the lab findings on platelet clumping
• have surgery booked, for the same reason; tell your surgical team what supplements you take
• have an autoimmune condition or take immunosuppressant medicine, since mushroom compounds act on immune cells in the lab
• have a known mushroom allergy, asthma or a history of allergic reactions
• are under 18, as the trials were all in adults

Stop taking it if you get a rash, breathing problems or stomach upset that does not settle. If you have swelling of the face or throat or difficulty breathing, call 999.

There is no official recommended amount, in the UK or anywhere else. The only sensible guide is the dose on the label of the product you buy, and the amounts used in trials give a sense of range.

• About 3 g a day of dried fruiting body powder for 16 weeks (Mori, 2009)
• 1.8 g a day for 28 days (Docherty, 2023)
• Three 350 mg capsules of erinacine A enriched mycelium a day for 49 weeks (Li, 2020)
• About 2 g a day of powder baked into cookies for 4 weeks (Nagano, 2010)
• A single 3 g dose of a 10:1 extract (Surendran, 2025)

Some writers suggest 3 to 5 g a day of dried mushroom for cognition, but that figure is not based on a trial that compared doses. Comparing numbers across products is tricky, because 1 g of a concentrated extract is not the same as 1 g of plain dried powder. The extract ratio, covered in the next section, tells you how much mushroom went in.

Most people take it in the morning with food. Nothing in the research favours one time of day, and the trials that saw differences ran for weeks, not days.

Lion's Mane is sold as capsules, tablets, powder, tinctures, gummies and coffee or cacao blends. No official standard exists for these products, so quality varies. Check the label for these.

• Fruiting body or mycelium. Fruiting body products carry more hericenones and beta-glucans. Mycelium products carry more erinacines, but mycelium grown on grain can end up containing a lot of leftover starch. A good label says which part is used.
• Extract or plain powder. Plain powder is dried, ground mushroom. An extract has been steeped in hot water, alcohol or both, with the solid material then removed.
• Extract ratio. A 2:1 extract means about two parts of dried mushroom went into each part of finished extract. A 10:1 extract is more concentrated. The ratio shows how much raw material was used, not how much of any particular compound ended up in it.
• Beta-glucan content. Some brands state a beta-glucan percentage. It is a better marker than the words polysaccharides, which can include starch from grain.
• Testing and the rest of the recipe. Look for batch testing for heavy metals and microbes. Check gummies for gelatine if you are vegan, and coffee blends for caffeine.

Be wary of any product that says it treats anxiety, dementia, ADHD or nerve damage. In the US the Food and Drug Administration has written to sellers about claims like these, and in the UK such wording breaks food law and advertising rules.

If you can find it fresh, Lion's Mane is a very good eating mushroom. Cooked, it has a mild, slightly sweet flavour and a stringy, meaty texture that many people compare to crab, lobster or scallops. It is usually cooked rather than eaten raw.

• Tear it into pieces along the grain rather than slicing it, so it keeps its texture.
• Dry fry it in a hot pan first to drive off water, then add butter or oil and cook until golden.
• Press thick slices under a heavy pan for crisp mushroom steaks, or roast it as a meat alternative.
• Add torn pieces to stir fries, risotto, pasta, soups and stews, or pile it on toast.
• Use dried Lion's Mane or the powder in broths, stocks and baking, or stir the powder into hot water, tea, coffee or smoothies.

Pick white or cream mushrooms with no brown, wet patches and use them within a few days. Cooking changes some of the compounds, and nobody has tested whether eating the fresh mushroom gives the same results as the supplements in the trials.

In the UK, Lion's Mane supplements are sold as food supplements, which are regulated as foods, not medicines. They do not need approval before sale. Local trading standards and the Food Standards Agency enforce food law, and the Advertising Standards Authority polices the wording in ads.

What that means on a label:

• Health claims on foods must appear on the GB Nutrition and Health Claims Register. There are no authorised claims for Lion's Mane or any other mushroom extract. Claims for botanical ingredients have been on hold for years.
• No food or supplement may claim to prevent, treat or cure a disease. A product that did would be treated as an unlicensed medicine by the MHRA.
• Authorised claims exist for some vitamins and minerals. For example, zinc contributes to normal cognitive function. If a Lion's Mane product mentions memory or focus, check whether that wording is attached to an added vitamin or mineral rather than to the mushroom.

The NHS does not publish specific guidance on Lion's Mane. Its general advice on supplements applies: speak to a GP or pharmacist before taking one if you are pregnant, breastfeeding or on medicine.

Supplements are sold by high street chains such as Holland & Barrett and Boots, independent health food shops and online brands. Fresh mushrooms come from UK specialist growers and farmers' markets, and grow-at-home kits are easy to find online.

Two Starshroooms gummies contain a 2:1 Lion's Mane extract, alongside Reishi, Chaga, Maitake, Cordyceps and Tremella, plus Panax Ginseng. They are blackcurrant flavoured, vegan and caffeine free. Most people take their two gummies with breakfast.

The studies on this page tested Lion's Mane on its own, often in different forms and at different amounts, and none of them tested our gummies. We link to them so you can see what has been studied and make your own decision.

If you want to try the combination, the Trial Pack has 10 gummies, which is about five days. The Full Pack has 60 gummies, one month's supply, for £24.99. Since the trials ran for weeks rather than days, a full pack is the fairer way to judge whether it suits your routine.

You can read about the other ingredients in our guides to Reishi, Cordyceps, Chaga, Maitake, Tremella and Panax Ginseng, see the full list of studies on our research page, or browse all our mushroom gummies.