Reviewed
Reviewed on 2026-09-19 against the evidence rules: every claim carries a grade, every claim and every safety flag carries a source, and every citation was re-resolved against the record it names. The read was delegated by the owner on 2026-09-18 and signed by the Lead on his behalf (D-295) — it is a delegated review, not the owner's own reading of the page. Every claim on it carries an evidence grade and a named weakest link. It is educational and is not medical advice.
Last reviewed
Four small human trials, four different preparations, and no trial at all of the branded product most readers are about to buy. This is the dossier where the difference between an ingredient and a product does all the work.
Safety
Adverse effects
The US LiverTox monograph gives Lion's Mane its lowest concern rating and records that it has not been linked to liver enzyme elevations or clinically apparent liver injury. Gastrointestinal complaints appeared in fewer than one in ten trial participants and rarely stopped anyone continuing.
Who should not
One acute hypersensitivity reaction to oral Lion's Mane is described in the literature. Anyone with a mushroom allergy should not take it.
Product quality
Fruiting body and mycelium are different materials with different chemistry, and mycelium products are frequently grown on grain that stays in the finished powder. Every human trial above names which one it used; a label that says only "Lion's Mane" has not told you what is in it.
No data in your group
There is no trial in pregnancy and none in under-18s. There is one 28-day trial in healthy adults under 45, and it is a pilot.
What the evidence says, and how strong it is
A grade belongs to one claim, in one population, for one preparation — never to a compound, a food or a page. Open a grade to see the four links between the evidence and the thing you would actually do, and which of them is doing the least work.
In one 16-week trial of 30 adults aged 50 to 80 with mild cognitive impairment, a fruiting-body powder improved scores on a cognitive function scale at weeks 8, 12 and 16 against placebo, and the scores fell again four weeks after the powder stopped.
Evidence grade C: Early research suggestsIn whom: Japanese adults 50–80 with mild cognitive impairment
What form: Fruiting-body powder, 96% dry, 3 g/day for 16 weeks
Measured as: Global cognition on the Revised Hasegawa Dementia Scale
Why this grade
- Weakest link
- Population — the people studied are not the people reading. Thirty Japanese adults aged 50 to 80 who already had mild cognitive impairment, and the scores fell again once the powder stopped — not the reader of this page.
- What was actually studied
- Japanese adults 50–80 with mild cognitive impairment (n = 30)
- Detail worth knowing
- Four 250 mg tablets of 96% dry fruiting-body powder three times daily for 16 weeks, then 4 weeks off treatment.
In a 12-week randomised trial of a fruiting-body supplement, the MMSE moved and the two other tests run alongside it — a visual retention test and a verbal paired-associate test — did not.
Evidence grade C: Early research suggestsIn whom: Adults taking a fruiting-body supplement for 12 weeks
What form: Fruiting-body supplement, dose not stated in the abstract
Measured as: MMSE score, with the two other tests of cognition null in the same trial
Why this grade
- Weakest link
- Outcome — what was measured is not what you would notice. One of the three cognitive tests in the trial moved and the other two did not, which is the shape of a chance finding as much as of an effect.
- What was actually studied
- Adults taking a fruiting-body supplement for 12 weeks
- Detail worth knowing
- Three tests run; MMSE moved and the Benton visual retention test and the standard verbal paired-associate test did not. The abstract reports no group size.
In a 49-week pilot trial in patients with mild Alzheimer's disease, a solid-culture erinacine-A mycelium preparation was reported to improve MMSE scores within the treated group, and the instrumental-activities-of-daily-living score was the measure that differed between the groups. This is what that trial measured in that group; it says nothing about a healthy adult and this site makes no claim from it.
Evidence grade D: Human evidence insufficientIn whom: Patients with mild Alzheimer's disease
What form: Solid-culture erinacine-A-enriched mycelia, 350 mg capsules at 5 mg/g erinacine A, three per day for 49 weeks
Measured as: MMSE and instrumental activities of daily living in a disease population — context only, never a Brainmaxing claim
Why this grade
- Weakest link
- Population — the people studied are not the people reading. The participants had mild Alzheimer's disease. A disease population cannot validate anything for a healthy reader, and this site makes no claim from this trial at all.
- What was actually studied
- Patients with mild Alzheimer's disease
- Detail worth knowing
- Solid-culture EAHE mycelia, 350 mg capsules containing 5 mg/g erinacine A, three per day for 49 weeks. NCT04065061. Several authors are employees of Grape King Bio Ltd, which makes the preparation.
In a pilot trial of 41 healthy adults aged 18 to 45, a single 1.8 g dose was followed by faster Stroop performance an hour later, and 28 days of the same dose produced only a trend towards lower self-reported stress. The authors record null and limited negative findings elsewhere in the same trial and ask for caution.
Evidence grade C: Early research suggestsIn whom: Healthy adults 18–45
What form: Fruiting body, 1.8 g/day, single dose and 28 days
Measured as: Speed on the Stroop task 60 minutes after a single dose
Why this grade
- Weakest link
- Outcome — what was measured is not what you would notice. One task at one time point an hour after a single dose, with null and mildly negative findings around it in the same pilot.
- What was actually studied
- Healthy adults 18–45 (n = 41)
- Detail worth knowing
- 1.8 g/day. Stroop faster 60 min after a single dose (p = 0.005); a trend towards reduced subjective stress after 28 days (p = 0.051); the authors record null and limited negative findings elsewhere and ask for caution. Product supplied by Sempera Organics, which had no role in design or analysis.
The maker of Erinamax states that it supports cognitive function, memory and nerve growth factor production. No trial of Erinamax exists. The one human trial of an erinacine-A preparation used solid-culture mycelia at 5 mg per gram, in patients with mild Alzheimer's disease, for 49 weeks — a different preparation in a different group, searched on 2026-08-23.
Evidence grade E: Seller's claim — not supported by a study of this productIn whom: Healthy adults
What form: Erinamax — liquid-culture Hericium erinaceus mycelium, 500 mg per capsule at 2.5 mg erinacine A, 5 mg erinacine A per two-capsule serving
Measured as: Any cognitive outcome
Why this grade
- Weakest link
- Preparation — what was tested is not what is sold. There is no trial of Erinamax at all: the one erinacine-A trial used solid-culture mycelia at 5 mg per gram in patients with mild Alzheimer's disease, and a different preparation inherits nothing from it.
- What was actually studied
- Not applicable — a composition statement, not a study; Patients with mild Alzheimer's disease
- Detail worth knowing
- States liquid-culture Hericium erinaceus mycelium, 500 mg per capsule with 2.5 mg erinacine A, and 5 mg erinacine A per two-capsule serving. The page also asserts support for cognitive function, memory, nerve growth factor production and neuroplasticity, under the FDA structure/function disclaimer.
- Solid-culture EAHE mycelia, 350 mg capsules containing 5 mg/g erinacine A, three per day for 49 weeks. NCT04065061. Several authors are employees of Grape King Bio Ltd, which makes the preparation.
Everything above, and where it comes from
- Mori K, Inatomi S, Ouchi K, Azumi Y, Tuchida T (2009). Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial. Phytotherapy Research 23(3):367–372
- Saitsu Y, Nishide A, Kikushima K, Shimizu K, Ohnuki K (2019). Improvement of cognitive functions by oral intake of Hericium erinaceus. Biomedical Research 40(4):125–131
- Li IC, Chang HH, Lin CH, et al. (2020). Prevention of Early Alzheimer's Disease by Erinacine A-Enriched Hericium erinaceus Mycelia Pilot Double-Blind Placebo-Controlled Study. Frontiers in Aging Neuroscience 12:155
- Docherty S, Doughty FL, Smith EF (2023). 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 15(22):4842
- Nootropics Depot. Erinamax — Hericium erinaceus liquid-culture mycelium, product page. nootropicsdepot.com
- National Institute of Diabetes and Digestive and Kidney Diseases. Lion's Mane — LiverTox: Clinical and Research Information on Drug-Induced Liver Injury. NCBI Bookshelf NBK599740
The one thing worth doing
If you are going to test this on yourself anyway, decide in advance which single thing you will notice, write down where it is today, and check it in four weeks. That costs nothing and it is the only part of this page that is about you.
Regulatory note — this note has not yet been reviewed by a lawyer. In the United States, supplements are sold under DSHEA: a structure/function claim is not reviewed by the FDA before it appears, and the label must carry the words "This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease." In the EU and the UK, only health claims on the authorised register may be used in advertising, and a food or supplement advertisement may not say a product prevents, treats or cures a disease. Whether an evidence page that carried a purchase link would itself count as advertising under those rules is an open question that counsel, not this page, will answer; there are no purchase links here. Nothing on this page is medical advice.