Lion's Mane and Cognition: What the Human Trials Show

Lion’s mane (Hericium erinaceus) is an edible mushroom sold as a “brain” supplement. The human evidence is a handful of small trials, several tied to companies that sell the mushroom, with mixed results and no meta-analysis. The nerve growth factor (NGF) story comes from cell and rodent work. On the claim that it is “cope”, the fair reading is partly supported: no trial shows a reliable benefit in healthy adults, but it is not an empty placebo story either.

Key points

• Human trials are small (18 to 109 people) and short (a single session to about a year). The one trial in mild cognitive impairment had 30 participants [1].
• Results in people without a diagnosis are mixed: one trial found faster responses on a single task, another found no effect on its main outcome [3][4]. The newest and largest trial is positive but is an abstract only so far [5].
• Hericenones (fruiting body) and erinacines (mycelium) are the compounds linked to NGF in cells and rodents. No human trial measured NGF in the brain [8].
• In the EU, a lion’s mane mycelium powder is a novel food; fruiting-body extract powders are listed as not novel [9]. In the US it is sold as a dietary supplement, and the FDA has acted against disease claims [11][12].

What is in it, and how it was studied

Two groups of compounds get the attention. Hericenones are reported only in the fruiting body; erinacines are the compounds measured in cultured mycelium [7][8]. A 2025 systematic review of preclinical work (23 studies, cell lines and rodents) found that erinacines enhanced NGF-driven neurite outgrowth in PC12 cells and induced NGF release from astrocyte-type cells. Erinacine A did not raise NGF output on its own, which led the authors to suggest it may increase NGF potency rather than NGF expression [8].

For hericenones the same review says only that they stimulate NGF synthesis in vitro, and only in glial cells. It did not assess them, because it excluded fruiting-body studies [8]. A 2014 review calls polysaccharides the main active components [15]. Binding targets are unknown and erinacine content was often unreported [8].

That is the basis for “lion’s mane grows nerves”, and it is cell and rodent work. The review notes earlier work suggesting some compounds cross the blood-brain barrier, but did not evaluate absorption [8].

Human trials you can open

Trial	Population	Size, length, design	Product as described	Funding or ties
Mori et al., Phytotherapy Research 2009 [1]	Japanese adults 50-80 with mild cognitive impairment	30 randomized (15 and 15), 16 weeks, double-blind, placebo-controlled	Yamabushitake tablets; part of the mushroom not stated in the record I read	First author at Hokuto Corporation (mushroom company); no grant listed in the record
Saitsu et al., Biomedical Research 2019 [2]	Adults, population not stated on the page I read	12 weeks, double-blind, placebo-controlled; a later review lists N=31 [7]	Fruiting body	No funding or conflict statement on the page
Li et al., Frontiers in Aging Neuroscience 2020 [6]	Mild probable Alzheimer’s, mean age about 74-77	49 randomized, 41 finished, 49 weeks, pilot	Erinacine A-enriched mycelia	Grape King Bio paid salaries of five authors and supplied materials
Docherty et al., Nutrients 2023 [3]	Healthy adults 18-45	43 randomized, one session plus 28 days, parallel pilot	Proprietary “organic mushroom complex”; part not specified	Product supplied by Sempera Organics; no other funding
Surendran et al., Frontiers in Nutrition 2025 [4]	Healthy adults 18-35	18, one session, crossover	Water-ethanol fruiting-body extract	Two authors employed by Beyond Alcohol Ltd., which uses lion’s mane; the company helped pay the publication fee
Grant et al., Frontiers in Nutrition 2026 [5]	Adults 40-75 with self-reported cognitive difficulty	109 evaluated (57 and 52), 8 weeks, double-blind	Fruiting body plus mycelial biomass	Funding statement not visible in the abstract page; two authors affiliated with M2 Ingredients

Mild cognitive impairment (Mori). The treated group scored higher than placebo at weeks 8, 12 and 16 on a scale based on the Revised Hasegawa Dementia Scale, then dropped significantly four weeks after stopping. Laboratory tests showed no adverse effects [1]. Thirty people and a company-affiliated first author make this a lead, not a firm result. I could not open the full text, so product details beyond “tablets” are unverified.

Mild Alzheimer’s (Li). Within-group, the treated arm’s MMSE rose from 21.75 to 23.2 at week 49 (p=0.035) and the placebo arm’s CASI score fell at week 25. Between-group differences on the cognitive scales were not significant; a daily-living score favoured the treated arm (p=0.012) [6]. Seven of 49 left for efficacy or side-effect reasons, and the paper gives two different dropout rates (14.3% and 8.2%) [6].

Adults without a diagnosis. Saitsu reported that the MMSE alone showed significant improvement, while the other two tests were not reported as significant in the abstract [2]. In Docherty, the treated group responded faster on a Stroop task an hour after one dose (688 vs 738 ms at baseline, p=0.005), but also recalled fewer words than before, and no effect appeared on the other individual tasks or global scores. A stress score was lower on day 29 (p=0.033) [3].

Surendran found no effect on the global cognition or mood composites. A pegboard test improved, a Flanker task was worse, and the authors called the results inconclusive [4]. Grant, the largest trial, reports greater gains on a visual attention and working-memory task (p<0.05), plus sleep, restedness and mood, with “no adverse events” in the treated group. Only the abstract page was available, with no exact statistics, no designated primary outcome and no funding statement. The final version had not been published at the time of reading [5].

Reviews. A 2025 systematic review (PubMed only, 26 studies, 5 randomized trials) calls the effectiveness “limited” and says a meta-analysis was not possible because of incomplete reporting [7]. Its abstract nonetheless reports a pooled MMSE gain of 1.17 drawn from one trial and one pilot, and its text gives other figures (0.81 in the Discussion), so that number should not be relied on [7]. I did not find a meta-analysis of randomized trials.

Fruiting body or mycelium

The products are not the same thing. Fruiting bodies carry hericenones; mycelium grown in culture carries erinacines, and erinacine A-enriched mycelium is a manufactured ingredient [7][8]. The Alzheimer’s pilot used mycelium [6]; Saitsu and Surendran used fruiting body [2][4]; Grant used a blend [5]; Mori and Docherty do not say in the records I read [1][3]. The 2025 review does not compare the forms and contradicts itself on which compounds come from which part [7]. Results cannot be pooled across these products.

Regulatory status

• European Union. The Commission’s novel food consultation list (page opened 2026-11-08, undated as a whole) has three Hericium entries. “Dehydrated mycelium powder” is a novel food (consultation 29 October 2019). A fruiting-body extract powder is “not novel” (28 February 2025, an ultrasound-extraction product) and a “powder extract from the fruiting body” is “not novel” (10 September 2026) [9]. The list is non-binding [9]. A 2025 review notes the general rule that fruiting bodies of known edible mushrooms are treated as food while mycelium is a novel food [10]. EU health claims and national positions in Germany were not checked, nor were the UK or EMA.
• United States. I found no FDA drug approval for lion’s mane. It is sold as a dietary supplement under the 1994 DSHEA framework, where manufacturers are responsible for safety and labeling before marketing [11]. Disease claims turn a product into an unapproved drug: a FDA/FTC action in February 2019 named a lion’s mane product among seven, over dementia and Alzheimer’s claims [13], and a July 2021 FDA letter cited claims about dementia, depression and ulcers [12]. I did not check GRAS notices or FDA’s treatment of mycelium.

Risks and unknowns

Trials report little harm, but safety reporting is thin. Docherty and Surendran do not report adverse-event results in the text I read [3][4]. In Li, three treated participants left because of abdominal discomfort, nausea or skin rash [6]. The 2025 review lists stomach discomfort, diarrhea, headache, nausea, skin rash and allergic reactions, adding that side effects are “commonly unreported” [7].

The one serious case it describes is a 2003 report from Japan of a 63-year-old man with untreated mild diabetes who developed acute respiratory distress syndrome after regular use of a dry extract. A lymphocyte test with the extract was positive, which the report read as an allergic reaction. The review says causality cannot be assumed [7]. I tried to verify a separate reported lion’s mane anaphylaxis case and could not, so I do not cite it.

People with mushroom allergy are the obvious at-risk group. Not studied in the trials I read: use beyond about a year, children, pregnancy, interactions with prescription drugs, and how much active compound reaches the brain. Product content varies and is often unreported [8].

What the post claims

The @Hoostethics post of 15 October 2026 reads “ranking the most cope supplements.” and is an image. I could not see the image; my text read through the fxtwitter mirror has no description, and the project’s transcription of it lists lion’s mane under “Cope” [14]. See also the cope supplements tier list check.

Verdict: partly supported. If “cope” means the benefit is unproven for healthy people, that holds: the healthy-adult trials are small, short, positive on isolated tasks at best, and the largest one is not yet fully published [3][4][5]. If it means nothing is going on, that overreaches: there are consistent, if weak and company-adjacent, signals in older adults with impairment or complaints [1][5][6], and plausible cell mechanisms [8]. Large, independent, preregistered trials are the gap.

Frequently asked questions

Does lion’s mane improve memory in healthy adults? The trials do not show a consistent effect. One 43-person pilot found faster responses on one task but fewer words recalled; an 18-person crossover found no change in its main outcome [3][4].

Is there a meta-analysis? I did not find one. A 2025 systematic review of 26 studies said pooling was not possible, though its abstract quotes a pooled figure that conflicts with its text [7].

Is lion’s mane approved by the FDA or EMA? No drug approval was found. In the US it is a dietary supplement; in the EU fruiting-body extracts are listed as not novel and mycelium powder as a novel food [9][11].

Does lion’s mane raise NGF in humans? That has not been shown. NGF effects come from cell and rodent studies, mostly with erinacines from mycelium [8].

Sources

1. Mori K. et al., “Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment”, Phytotherapy Research 23(3) (2009). https://pubmed.ncbi.nlm.nih.gov/18844328/ (PubMed blocked automated access; abstract read through the Europe PMC record; full text not opened)
2. Saitsu Y. et al., “Improvement of cognitive functions by oral intake of Hericium erinaceus”, Biomedical Research 40(4) (2019). https://www.jstage.jst.go.jp/article/biomedres/40/4/40_125/_article
3. Docherty S., Doughty F., Smith E., “The Acute and Chronic Effects of Lion’s Mane Mushroom Supplementation on Cognitive Function, Stress and Mood in Young Adults”, Nutrients 15(22):4842 (2023-11-20). https://pmc.ncbi.nlm.nih.gov/articles/PMC10675414/
4. Surendran G. et al., “Acute effects of a standardised extract of Hericium erinaceus on cognition and mood in healthy younger adults”, Frontiers in Nutrition 12 (2025-04-10). https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2025.1405796/full
5. Grant A. et al., “A randomized, double-blind, placebo-controlled study evaluating the impact of Hericium erinaceus (Lion’s Mane) on cognitive performance and wellbeing”, Frontiers in Nutrition 13 (accepted 2026-10-11; abstract page only). https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2026.1904820/abstract
6. Li I-C. et al., “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 (2020). https://pmc.ncbi.nlm.nih.gov/articles/PMC7283924/
7. Menon A. et al., “Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review”, Frontiers in Nutrition 12:1641246 (2025-09-01). https://pmc.ncbi.nlm.nih.gov/articles/PMC12434001/
8. Spangenberg E.T. et al., “Unveiling the role of erinacines in the neuroprotective effects of Hericium erinaceus: a systematic review in preclinical models”, Frontiers in Pharmacology (2025-06-23). https://www.frontiersin.org/journals/pharmacology/articles/10.3389/fphar.2025.1582081/full
9. European Commission, “Consultation process on novel food status” (no page date). https://food.ec.europa.eu/food-safety/novel-food/consultation-process-novel-food-status_en
10. Bergmann P. et al., “Mycelium as Food: When will it be approved as a Novel Food?”, Ernaehrungs Umschau international (09/2025). https://www.ernaehrungs-umschau.de/fileadmin/Ernaehrungs-Umschau/pdfs/pdf_2025/09_25/EU09_2025_M544_M549_en.pdf (abstract only read)
11. FDA, “Dietary Supplements” (current as of 2024-10-01). https://www.fda.gov/food/dietary-supplements
12. FDA, Warning letter to Brilliant Enterprises LLC (2021-07-20). https://www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/warning-letters/brilliant-enterprises-llc-609523-07202021
13. FTC, “FTC, FDA send warning letters to companies selling dietary supplements claiming to treat Alzheimer’s disease” (2019-02-11). https://ftc.gov/news-events/press-releases/2019/02/ftc-fda-send-warning-letters-companies-selling-dietary
14. @Hoostethics, post “ranking the most cope supplements.” (2026-10-15). https://x.com/Hoostethics/status/2110728908735979632 (text read through the fxtwitter mirror; image not viewed; tier placement from the project’s transcription)
15. Wang M. et al., “Hericium erinaceus (Yamabushitake): a unique resource for developing functional foods and medicines”, Food & Function 5(12) (2014-12). https://pubmed.ncbi.nlm.nih.gov/25317734/ (abstract via Europe PMC)

This article is information, not medical advice.