Supplement: Leeuwenmanenpaddenstoel (Lion's Mane)

What Is Lion's Mane?

The shaggy white mushroom grows on hardwood, its fruiting body a fist of soft dangling spines. Japan calls it Yamabushitake, after the yamabushi mountain ascetics. China prized it for centuries as food and as medicine, one of the dishes of the imperial table.

What the Human Trials Show

Every human trial of lion's mane enrolled at most a few dozen people and ran at most a few months, starting with Mori's study in 2009. All of them lean the same way, toward benefit.

The clearest result comes from one controlled trial in mild cognitive impairment (Mori 2009). The gain reversed within about a month of stopping. A small Alzheimer's pilot ran over nearly a year, and everyday function improved while the cognitive-test scores were no better than placebo (Li 2020). Weakest are the mood and healthy-adult results, one short trial each, and their findings do not all line up (Nagano 2010; Docherty 2023; Biomed Res 2019).

The Research & Studies

Everything here is based on the research we have collected and checked, sorted into groups and ordered with the strongest evidence first. Click any claim to open the studies behind it.

Cognition

Lion's mane raised cognitive-test scores over 16 weeks in 30 adults with mild cognitive impairment, and the gain faded after stoppingEmerging

In plain terms

Older people with early memory decline scored better on a thinking test while taking lion's mane for four months, and the improvement faded within a month of stopping.

In detail

A double-blind, placebo-controlled trial randomized 30 Japanese adults (ages roughly 50 to 80) with mild cognitive impairment to lion's mane fruiting-body powder (3 g/day, as tablets) or placebo for 16 weeks. The treatment group scored significantly higher on the Hasegawa Dementia Scale-Revised at weeks 8, 12 and 16, with scores improving over time. At a 4-week follow-up after stopping, scores had declined, suggesting the benefit depended on continued intake. The study is small and short, and the outcome is a cognitive screening scale, so it is an encouraging early signal, not a definitive result.

The study · 1

Mori et al. 2009, Phytother Res · Phytother Res

An erinacine-rich mycelium improved daily function, with cognitive scores trending up, over 49 weeks in an early-Alzheimer's pilotPreliminary

In plain terms

People with early Alzheimer's who took an erinacine-rich lion's-mane mycelium for nearly a year did better on memory and everyday-function tests than those on a placebo.

In detail

A pilot double-blind, placebo-controlled study assigned patients with mild Alzheimer's disease to an erinacine-A-enriched H. erinaceus mycelium (three 350 mg capsules/day, each containing 5 mg/g erinacine A) or placebo for 49 weeks; of 68 recruited and 49 randomized, 41 completed (20 treatment, 21 placebo; 17 men and 24 women). The one between-group difference on a cognitive or functional measure to reach significance was Instrumental Activities of Daily Living at week 49, higher on the mushroom (p=0.012). Mini-Mental State Examination scores rose significantly within the treatment group from baseline (p=0.035) but did not differ significantly from placebo, and Cognitive Abilities Screening Instrument scores showed a non-significant upward trend as the placebo group's scores declined. Some biomarker and neuroimaging measures moved favorably. The sample was small and this is an early pilot, so it establishes a first human signal in Alzheimer's, not proven efficacy.

The study · 1

Li et al. 2020, Front Aging Neurosci · Front Aging Neurosci

A single 1.8 g dose sped a thinking task in healthy adults, while 28-day use gave small, mixed resultsPreliminary

In plain terms

In healthy people, lion's mane has shown small and patchy effects, a bit faster on one thinking task after a single dose, some hint of lower stress, and not much that lines up across studies.

In detail

A double-blind pilot in 41 healthy young adults found that a single 1.8 g dose of lion's mane improved speed of performance on a Stroop task about an hour later, while 28 days of supplementation produced a non-significant trend toward reduced subjective stress and no clear cognitive gain (Docherty 2023). A separate small controlled trial in healthy adults reported improved scores on a cognitive screening measure after 12 weeks of oral intake (Biomed Res 2019). Taken together these are small, short, heterogeneous studies with modest and not fully consistent results, best read as a preliminary signal in healthy people.

The studies · 2

Docherty et al. 2023, Nutrients · Nutrients

Saitsu et al. 2019, Biomed Res · Biomed Res

Mood & stress

Women around age 40 with perimenopausal complaints reported better mood after four weeks of lion's-mane baked goods, in a 30-woman pilotPreliminary

In plain terms

Women around age 40 with perimenopausal complaints who ate lion's-mane cookies for four weeks reported better mood than those given plain cookies.

In detail

A placebo-controlled pilot gave 30 Japanese women (mean age about 40, enrolled for perimenopausal and other indefinite complaints) cookies containing Hericium erinaceus or placebo cookies for four weeks; after exclusions, 26 were analyzed (12 on the mushroom, 14 on placebo). The lion's-mane group reported lower depression (CES-D) and indefinite-complaints (ICI) scores from their own baseline over the four weeks; between the groups, only two indefinite-complaint items, palpitations and one insensitivity measure, reached significance, while concentration, irritability and anxiety were non-significant downward trends. The study is very small, very short, and in a specific population, so it is a preliminary signal for mood, not evidence of a reliable antidepressant or anxiolytic effect.

Who this may not transfer to:The single mood trial enrolled only women (menopausal-age); whether the mood effect transfers to men is untested.

The study · 1

Nagano et al. 2010, Biomed Res · Biomed Res

How it works

Lion's mane raises nerve growth factor and sprouts new nerve connections in cell studiesPreliminary

In plain terms

In the lab, lion's mane and its active compounds make nerve cells produce more nerve growth factor and grow new connections. This is the mechanism behind the interest in memory and nerve repair.

In detail

Hericium erinaceus extracts and their isolated compounds have been shown in laboratory cell models to raise nerve growth factor (NGF). In human 1321N1 astrocytoma cells, the whole extract dose-dependently increased NGF mRNA expression and secretion, while the isolated hericenones did not, so the extract’s NGF-inducing compounds in that assay are not the hericenones (Mori 2008). Aqueous extracts have also promoted neurite outgrowth in cultured neurons, indicating neurotrophic activity (Lai 2013). These are in-vitro findings that establish a plausible mechanism; the open question is how much of this NGF effect reaches and acts in a living human brain, since NGF itself does not readily cross the blood-brain barrier.

The studies · 2

Mori et al. 2008, Biol Pharm Bull · Biol Pharm Bull

Lai et al. 2013, Int J Med Mushrooms · Int J Med Mushrooms

A compound that raises nerve growth factor in a laboratory dish has not yet been shown to reach a living human brain and act there.

How It Works

The interest in the brain is recent, traced to laboratory work first reported in the 1990s.

Anatomy of the Practice

1Two families of compounds

The fruiting body (the mushroom you eat) is rich in hericenones; the mycelium (the root-like network, usually grown on grain) is where erinacines concentrate. Both have been shown in the laboratory to stimulate nerve growth factor. That is one reason a fruiting-body product and a mycelium product are not interchangeable, and it is why trials name the one they used.

2Nerve growth factor

Nerve growth factor, or NGF, is a signaling protein that supports nerve-cell survival, maintains the connections between neurons, and aids regrowth after damage. In cell studies, lion's-mane extracts and their isolated compounds raise NGF production and promote neurite outgrowth, the sprouting of new connections between nerve cells.

3From the dish to the brain

How much of that laboratory effect reaches a living human brain is unknown. The NGF protein is a large molecule and does not easily cross from the blood into the brain; the smaller erinacines are the likelier candidates for crossing. The human trials measure memory and mood, and none measures NGF directly.

How to Take It

Ways to Do It

Cooking and eating the fresh mushroom is how lion's mane was taken for centuries in China and Japan, and it carries the food history the tradition rests on. Beyond the whole food, the studied approach is a daily dose of a well-characterized product, kept up for a couple of months so you can judge it. A fruiting-body extract with a stated beta-glucan number tells you more about what you are getting than the brand name does. Trials used 1 to 3 grams a day; there is no single established dose.

1

Take 1 to 3 grams a day of a fruiting-body product$Easy

The clearest cognition trial used 3 grams a day of powdered fruiting body. Common supplement doses run from about 500 mg to 3 grams a day of a fruiting-body extract or powder. The fruiting body carries the longest food history and the hericenone compounds. Take it with a meal every day; in the trials the effect built up over several weeks of steady use.

2

Give it 8 to 16 weeks, then judge whether it is doing anything$Easy

The trials ran roughly two to four months, so it is taken continuously rather than as a single dose. The studied window is the point to look for any change, measured against how you were before you started.

3

Read the label for fruiting body versus mycelium, and for fillers$Easy

Read the label. A stated fruiting-body source, or a measured beta-glucan number, tells you the capsule holds actual mushroom rather than grain.

4

A third-party-tested fruiting-body extract stating its beta-glucan content$$Easy

A fruiting-body extract from a brand that runs independent third-party testing and states a measured beta-glucan percentage tells you the tub holds what the label claims. It is also free of the heavy metals and contaminants that mushrooms can concentrate. A plain fruiting-body powder is the same material in a simpler form.

Go Deeper

• Placebo and its power: why a benefit that works partly through expectation is still a benefit worth having, useful when reading small, subjective supplement trials.
• How we grade evidence: what emerging and preliminary mean, and why a strong laboratory mechanism and a handful of small human trials are graded separately.

The Chinese Medicine View

Cautions For This Practice

Everything to be aware of is here, in one place. This practice suits most healthy people; a few situations call for real care.

Allergy and breathing reactions

Lion's mane is a mushroom and a food, and like any mushroom it can cause allergic reactions in people who are sensitive to it. Case reports describe skin rashes from contact and, rarely, breathing problems after eating or inhaling it. If you have a known mushroom allergy, or you develop itching, a rash, or any difficulty breathing after taking it, stop and seek care. Start with a small amount the first time so you can see how you react.

Product quality and what is actually in the tub

Mushroom supplements are loosely regulated and vary a great deal. Mycelium products are grown on grain and often dried with the grain still in, so a share of the powder is grain starch rather than mushroom. Mycelium carries the erinacine compounds, but it is a different material, tested in different trials, and a result shown for one does not automatically carry to the other. Mushrooms also concentrate heavy metals from where they grow.

Blood sugar, bleeding, and surgery

Early laboratory and animal work suggests lion's mane may lower blood sugar slightly and may have a mild blood-thinning action. The human evidence for either is thin. If you take medication for diabetes or a blood thinner, raise it with the doctor handling that treatment before you start. Stopping it a couple of weeks before any planned surgery is a sensible precaution.

Pregnancy and breastfeeding

There is not enough safety data on concentrated lion's-mane supplements during pregnancy or breastfeeding to judge them. The cautious course is to treat it as an ordinary food during those times, if at all, and to leave the concentrated supplement aside.

Start slow, be smart, read the research, and consult a professional if you have any concerns. This is here to inform your choice, not make it for you.

Common Questions

Does lion's mane improve memory?

The early evidence points that way and is limited. In a trial of 30 older adults with mild cognitive impairment, memory-test scores rose over 16 weeks and slipped back within a month of stopping. A pilot in early Alzheimer's disease found better daily function over nearly a year, while the cognitive-test scores did not separate from placebo. These are small, short studies using different preparations, so they show a consistent early signal, not a settled effect. Alongside its long use as a food and tonic, lion's mane has early promise for the brain and a human evidence base still too thin to call it a treatment.

What is the difference between fruiting body and mycelium?

The fruiting body is the mushroom you would recognize and eat, and it is rich in compounds called hericenones. The mycelium is the root-like network the mushroom grows from, usually cultivated on grain, and it concentrates different compounds called erinacines. Both raise nerve growth factor in laboratory studies, but they are different materials tested in different trials, so a benefit shown for one does not automatically apply to the other. Many cheaper products are mycelium grown on grain and dried with the grain in. That can leave mostly starch, so read the label.

How much lion's mane should I take, and for how long?

The clearest cognition trial used 3 grams a day of powdered fruiting body, and common supplement doses run from about 500 mg to 3 grams a day of a fruiting-body extract or powder, taken with a meal. Any effect in the trials built over weeks, and in the mild-cognitive-impairment study it faded within a month of stopping, so give it eight to sixteen weeks and judge it against how you were before. If nothing has shifted in that window, it is not working for you.

Is lion's mane safe?

For most people it is well tolerated, and it has a long history as an ordinary food across East Asia. Because it is a mushroom, it can cause allergic reactions in people who are sensitive, from skin rashes to, rarely, breathing problems, so it is sensible to start small. The larger practical issue is product quality, since many supplements are mostly grain-grown mycelium with little actual mushroom, and mushrooms can concentrate heavy metals, which is why a third-party-tested fruiting-body product matters. The full detail is in the Cautions section above.

How does lion's mane work in the body?

Its most-studied mechanism is nerve growth factor. Compounds in the mushroom, hericenones from the fruiting body and erinacines from the mycelium, raise the production of NGF in cell studies and promote the sprouting of new connections between nerve cells. NGF keeps neurons healthy and supports their regrowth. That is why the research has looked at memory and mood. The open question is how much of that laboratory effect reaches a living human brain, which is why the effect is plausible but not yet shown in a living person.