Lion’s Mane Mushroom: Benefits, Dosage, Side Effects And Research

ByJustin Updated on

Lion’s mane mushroom (Hericium erinaceus) is an edible fungus sold as a nootropic supplement because animal and cell studies suggest its compounds can stimulate nerve growth factor (NGF). The human evidence is much thinner: a handful of small trials, mostly from Japan, found modest improvements on cognitive screening tests in older adults taking about 1 to 3 grams a day for several months. It appears to be well tolerated, but the hype around lion’s mane benefits runs well ahead of the data.

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Key Takeaways

  • Mostly preclinical: The NGF and neuroprotection findings come largely from animal and cell studies.[8]
  • Small human trials: The best-known trial gave 30 older adults with mild cognitive impairment about 3 g a day for 16 weeks; scores improved, then dropped after they stopped.[1]
  • Young, healthy adults: A 2023 pilot trial found only a single faster reaction-time result and a borderline drop in stress.[4]
  • Dose: Human studies used roughly 1 to 3 g a day of whole mushroom powder or about 1 g of an erinacine-enriched mycelium extract.[9]
  • Safety: Mild stomach upset is the most common complaint; allergic reactions are rare but reported.[9]

What Is Lion’s Mane Mushroom And How Does It Work?

Lion’s mane is a white, shaggy mushroom that grows on hardwood trees and has long been eaten in East Asia, where it is known in Japan as yamabushitake. It is a fungus, not a plant, although “lion’s mane plant” is a common search. Supplements are made from the fruiting body (the mushroom itself), the mycelium (the root-like network), or both.

Its reputation as a nootropic rests on two families of compounds: hericenones, isolated from the fruiting body, and erinacines, found mainly in the mycelium.[8] In laboratory and animal research, these compounds may stimulate the release of nerve growth factor, reduce inflammation and oxidative stress, and protect nerve cells from damage.[8] The mushroom also contains polysaccharides (including beta-glucans) and other compounds studied for antioxidant and immune effects.[7]

The key caveat: a review of these neurotrophic effects notes that the studies were conducted on animal models and that clinical trials are still needed.[8] Results in a mouse or a petri dish do not tell us whether a capsule changes NGF levels in a human brain.

Lion’s Mane Benefits: What Human Studies Show

Possible Benefit Evidence Strength Summary
Cognition in older adults with mild impairment Limited Two small Japanese RCTs found better scores on screening tests
Early Alzheimer’s disease Preliminary One 49-week pilot trial; most between-group differences not significant
Focus and memory in healthy young adults Preliminary One pilot RCT with mostly null results
Mood, anxiety and sleep Preliminary Two small studies suggest improvements
Nerve growth and neuroprotection Preclinical only Animal and cell data; not shown in humans

Lion’s Mane And Mild Cognitive Impairment

The trial most often cited for lion’s mane is a 2009 Japanese study of 30 adults aged 50 to 80 with mild cognitive impairment. Participants took four 250 mg tablets of dried fruiting-body powder three times a day (about 3 g daily) or placebo for 16 weeks. The lion’s mane group scored significantly higher on a cognitive function scale at weeks 8, 12 and 16. Four weeks after stopping, scores fell significantly, which suggests any benefit depends on continued use.[1] The trial was small, and the placebo group’s scores also rose at some time points.

A 2019 Japanese randomized, placebo-controlled trial gave fruiting-body supplements for 12 weeks. Mini-Mental State Examination scores improved compared with placebo, but two other memory tests did not.[2]

Lion’s Mane And Early Alzheimer’s Disease

A Taiwanese pilot trial gave 49 people with mild Alzheimer’s disease either placebo or about 1,050 mg a day of mycelium enriched with erinacine A (5 mg per gram) for 49 weeks. The lion’s mane group improved on daily-living activities compared with placebo, but differences on most cognitive tests were not statistically significant between groups. Four people dropped out because of abdominal discomfort, nausea or skin rash, and several authors worked for the company that made the product.[3] This is a hypothesis-generating study, not evidence that lion’s mane treats Alzheimer’s.

Lion’s Mane As A Nootropic For Healthy Adults

Most people buying lion’s mane nootropics are young and healthy, and that group has the least data. A 2023 UK pilot trial gave 41 healthy adults aged 18 to 45 either 1.8 g a day of lion’s mane or placebo for 28 days. Sixty minutes after a single dose, Stroop task speed improved, but no other cognitive test, global score or memory measure improved, and immediate word recall was actually worse after the first dose. After 28 days there was a borderline trend toward lower subjective stress. The authors called the study underpowered and urged caution.[4]

Mood, Anxiety And Sleep

A small 2010 study gave 30 women cookies containing lion’s mane fruiting body or placebo cookies for four weeks. Depression scores and some complaint scores fell in the lion’s mane group.[5] An Italian study in adults with overweight or obesity reported improvements in mood and sleep over 8 weeks using a mix of mycelium and fruiting-body extract at about 1.5 g a day.[6][9] Both studies were small, so this is preliminary.

A 2025 systematic review that pooled the available human research described the evidence base as heterogeneous and limited in size, with several trials lasting only one to four weeks.[9]

Lion’s Mane Dosage: How Much Should You Take Per Day?

Purpose Dose Duration Study
Mild cognitive impairment About 3 g/day fruiting-body powder (1 g three times daily) 16 weeks Mori 2009[1]
Cognitive function About 3.2 g/day fruiting-body powder 12 weeks Saitsu 2019[2][9]
Mild Alzheimer’s disease About 1,050 mg/day erinacine A-enriched mycelium 49 weeks Li 2020[3]
Cognition and stress (healthy adults) 1.8 g/day (three 600 mg capsules each morning) 28 days Docherty 2023[4]
Mood and sleep About 1.5 g/day mycelium plus fruiting-body extract 8 weeks Vigna 2019[6][9]

So how much lion’s mane should you take daily? Studies of whole mushroom powder used about 1 to 3 g a day, and the one mycelium extract trial used about 1 g a day of a product standardized for erinacine A.[9] Concentrated extracts are not directly comparable to whole powder, so follow the label of a product that tells you what it is standardized for. The older-adult trials lasted 12 to 16 weeks, so give it at least two to three months before deciding.

Best Time To Take Lion’s Mane

No study has compared morning with evening dosing. The 2023 healthy-adult trial dosed in the morning,[4] while the 2009 trial split the dose three times a day.[1] The practical answer is to take it at a consistent time each day, with food if it bothers your stomach, and split larger doses.

Forms: Fruiting Body Vs Mycelium, Extracts And Drops

This is the biggest point of debate in the lion’s mane supplement market.

  • Fruiting body: The mushroom itself. It is the source of hericenones, and most human trials used fruiting-body powder.[8][9]
  • Mycelium: The fungal network. Erinacine A appears only in fermented mycelium and is absent from fruiting bodies, which is the strongest argument for including mycelium.[8] The one Alzheimer’s pilot used an erinacine-enriched mycelium.[3]
  • Mycelium on grain: Many products are made from mycelium grown on a grain substrate. Critics argue the finished powder can include leftover grain that dilutes the active material; producers argue mycelium contributes compounds the fruiting body lacks. Without a lab report showing what is actually in the capsule, you cannot tell which camp a product falls into.
  • Heavy metals: One review notes lion’s mane can contain metals such as arsenic, cadmium and lead, and that mycelium tends to carry more than fruiting bodies.[8] Third-party testing matters.
  • Extracts, drops and tinctures: Hot-water or dual extracts concentrate certain compounds; tinctures (lion’s mane drops) vary widely in strength. None of these forms has head-to-head human data.

Researchers note that standardization of mushroom supplements is still in its early stages, with no uniform standards for quality or composition.[8] When choosing the best lion’s mane supplement, look for products that state which part of the mushroom is used, what the extract is standardized for (beta-glucans, hericenones or erinacines) and that publish third-party test results.

Lion’s Mane Spawn, Spores And Growing Kits

Lion’s mane spawn and spores are sold for growing your own mushrooms, not as supplements. Fresh lion’s mane is a well-regarded culinary mushroom, but eating it occasionally provides far less than the gram-per-day amounts used in trials.

Lion’s Mane Side Effects And Safety

Lion’s mane appears to be well tolerated in short-term human trials, though a 2025 systematic review noted that side effects often went unreported.[9]

  • Stomach upset: Mild stomach discomfort and diarrhea occurred at similar rates with lion’s mane and placebo in the 2009 trial.[1]
  • Nausea and rash: Led to dropouts in the 49-week Alzheimer’s pilot.[3]
  • Headache and allergic reactions: Listed among reported side effects across studies.[9]
  • Rare serious reaction: One case report described acute respiratory distress syndrome in a 63-year-old man who had taken lion’s mane extract long term, with testing that supported an allergic mechanism.[9]

Does Lion’s Mane Make You High?

No. Lion’s mane is a culinary mushroom, not a psychedelic (“magic”) mushroom, and none of the human trials described intoxicating effects. If you feel noticeably altered after taking a lion’s mane product, stop and check the label, since some blended “mushroom” gummies contain other ingredients.

Drug Interactions And Who Should Avoid Lion’s Mane

Well-documented drug interactions in humans have not been established, largely because the trials are small and short. As a precaution:

  • Avoid it if you are allergic to mushrooms or other fungi, given the allergy reports.[9]
  • Talk with a clinician first if you take diabetes medication, blood thinners or immune-suppressing drugs, or have a chronic illness, since interaction data is lacking.
  • Pregnant and breastfeeding women should avoid supplemental doses because safety has not been studied.

How Lion’s Mane Stacks With Other Nootropics

Lion’s mane is a slow, long-term ingredient, so it fits best alongside compounds with different roles:

None of these combinations has been tested in controlled trials. For ready-made templates, see our nootropic stacks guide and our roundup of the best nootropics.

Where To Buy The Best Lion’s Mane Supplement

Mind Lab Pro (Lion’s Mane In A Broad Stack)

Mind Lab Pro includes 500 mg of organic lion’s mane (fruiting body plus mycelium) per two-capsule serving. That is a meaningful amount, but it is still below the 1 to 3 g a day of whole mushroom used in most human trials. Mind Lab Pro is a reasonable choice if you want lion’s mane as part of a broad, well-tolerated daily formula with citicoline, bacopa, L-theanine and phosphatidylserine. If you specifically want to match a lion’s mane study dose, a standalone product is the better fit. Read our full Mind Lab Pro review.

Check Mind Lab Pro Price

Standalone lion’s mane: For a single-ingredient extract with published third-party testing, consider Nootropics Depot lion’s mane. On Amazon, buy only from listings marked “Sold by Nootropics Depot,” and check the label for the mushroom part used and what the extract is standardized for. More in our Nootropics Depot review.

Lion’s Mane FAQs

What Are The Main Lion’s Mane Benefits?

The most-studied benefit is modest improvement on cognitive screening tests in older adults with mild impairment after 12 to 16 weeks.[1][2] Claims about nerve regrowth are based on animal and cell research.[8]

How Much Lion’s Mane Should I Take?

Human trials used about 1 to 3 g a day of mushroom powder, or about 1 g a day of an erinacine-enriched mycelium extract.[9] Follow the label for concentrated extracts.

How Long Does Lion’s Mane Take To Work?

In the 2009 trial, differences from placebo appeared by week 8 and persisted to week 16.[1] Expect weeks to months, not hours.

Is Lion’s Mane Fruiting Body Or Mycelium Better?

Most human trials used fruiting body, but erinacine A is found only in mycelium.[8] No trial has compared the two directly, so a combined product or a well-tested fruiting-body extract are both reasonable.

Is Lion’s Mane Safe To Take Every Day?

Daily use for up to 49 weeks was generally well tolerated in small trials, with stomach upset and rare allergic reactions reported.[3][9]

Do The Effects Last After You Stop?

Probably not. In the 2009 trial, cognitive scores dropped significantly within four weeks of stopping.[1]

Medical disclaimer: This article is for educational purposes only and is not medical advice. Dietary supplements are not evaluated by the FDA to diagnose, treat, cure or prevent any disease. Talk with your doctor or pharmacist before starting a supplement, especially if you are pregnant, nursing, take prescription medication or have a medical condition. Read our full medical disclaimer.

References

  1. Mori K, et al. Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial. Phytother Res. 2009;23(3):367-372. PubMed
  2. Saitsu Y, et al. Improvement of cognitive functions by oral intake of Hericium erinaceus. Biomed Res. 2019;40(4):125-131. PubMed
  3. Li IC, et al. Prevention of early Alzheimer’s disease by erinacine A-enriched Hericium erinaceus mycelia pilot double-blind placebo-controlled study. Front Aging Neurosci. 2020;12:155. PubMed
  4. Docherty S, et al. The acute and chronic effects of lion’s mane mushroom supplementation on cognitive function, stress and mood in young adults: a double-blind, parallel groups, pilot study. Nutrients. 2023;15(22):4842. PubMed
  5. Nagano M, et al. Reduction of depression and anxiety by 4 weeks Hericium erinaceus intake. Biomed Res. 2010;31(4):231-237. PubMed
  6. Vigna L, et al. Hericium erinaceus improves mood and sleep disorders in patients affected by overweight or obesity: could circulating pro-BDNF and BDNF be potential biomarkers? Evid Based Complement Alternat Med. 2019;2019. PubMed
  7. Friedman M. Chemistry, nutrition, and health-promoting properties of Hericium erinaceus (lion’s mane) mushroom fruiting bodies and mycelia and their bioactive compounds. J Agric Food Chem. 2015;63(32):7108-7123. PubMed
  8. Szućko-Kociuba I, et al. Neurotrophic and neuroprotective effects of Hericium erinaceus. Int J Mol Sci. 2023;24(21):15960. PubMed
  9. Menon A, et al. Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review. Front Nutr. 2025;12:1641246. DOI

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