Lion's mane mushroom
Summary
Human evidence for lion's mane is limited to a few small trials. A 16-week trial in 30 older adults with early memory problems found better cognitive scores that faded after stopping. In healthy young adults, results were mostly null with one faster task after a single amount. Nerve-growth effects come from laboratory studies.
Key facts
- Dried fruiting-body powder (tablets, capsules, foods) and extracts; mycelium products contain erinacines[1][4]
- No head-to-head human data between fruiting-body and mycelium products in our sources[4]
- Cognitive scores in older adults with early memory problems ↑ (D); cognition and stress in healthy young adults: mostly null (D); mood and complaint scores in women: mixed (D)[1][2][3]
- Laboratory tests showed no adverse effects in a 16-week trial; a 2025 review lists stomach discomfort, headache and allergic reactions as possible, often unreported, side effects[1][4]
- 3 graded human outcomes on this page
- October 9, 2026
How it works
ProposedHericenones and erinacines from lion's mane stimulate nerve growth factor synthesis in laboratory studies, and erinacines show neural-stimulating activity; whether this happens in people is not established (proposed).[3][4]
What the human research says
Human trials only, one row per outcome. The form column shows what each trial actually tested. Grades follow our evidence-grading policy.
At a glance: strongest evidence per outcome
| Outcome | Grade | Effect | Strongest evidence | Rows |
|---|---|---|---|---|
| Focus | Grade D | Mixed | Pilot RCT · n = 41 · 2023 | 2 rows |
| Stress | Grade D | Mixed | RCT · n = 30 · 2010 | 1 row |
Every graded row
| Outcome | Effect | Grade | Best evidence | PMID |
|---|---|---|---|---|
| Cognition, stress and mood in healthy young adults | Mixed | Grade D | Pilot RCT · n = 41 · 2023 Healthy adults aged 18–45 Form: Lion's mane vs placebo · Dose: 1.8 g (single amount and daily) · Duration: Single amount and 28 days Participants were quicker on the Stroop task 60 minutes after a single amount, and subjective stress trended lower after 28 days (p = 0.051). Null and some negative findings were also observed. | 38004235 (opens PubMed)Source [2] |
| Cognitive function scores in older adults | Improved | Grade D | RCT · n = 30 · 2009 Japanese adults aged 50–80 with mild cognitive impairment Form: Tablets of 96% dried lion's mane fruiting-body powder vs placebo · Dose: Four 250 mg tablets three times a day (3 g/day) · Duration: 16 weeks, plus 4 weeks off Cognitive scale scores rose significantly more than placebo at weeks 8, 12 and 16, then fell significantly 4 weeks after stopping. Laboratory tests showed no adverse effects. | 18844328 (opens PubMed)Source [1] |
| Mood, sleep and general complaint scores in women | Mixed | Grade D | RCT · n = 30 · 2010 Women (menopause, depression, sleep and complaint indices measured) Form: Cookies containing lion's mane vs placebo cookies · Dose: Not stated in the abstract · Duration: 4 weeks Depression (CES-D) and complaint scores fell from baseline in the lion's mane group; versus placebo, only two complaint items ('insentive' and palpitations) were significantly lower, and concentration, irritation and anxiety only trended lower. | 20834180 (opens PubMed)Source [3] |
Forms
| Form | Elemental % | Absorption (human data) | GI tolerance | Studied for |
|---|---|---|---|---|
| Fruiting-body powder or extract (tablets, capsules, foods) | Varies[1] | No head-to-head human data[4] | No adverse effects on laboratory tests over 16 weeks at 3 g/day.[1] | Cognition, mood |
| Mycelium products (erinacine-containing) | Varies[4] | No head-to-head human data[4] | Possible stomach discomfort, headache and allergic reactions (review).[4] | Laboratory and early human studies |
Studied doses
Doses studied in human trials ranged from 1.8 to 3 g of lion's mane powder a day for 4 to 16 weeks; one acute study gave 1.8 g once.[2][1]
Interactions
Published interactions only: each row cites a source. No row means none was found in our sources, not that a combination is safe.
None found in our sources.
Who should be careful
- Mushroom allergy
- Allergic reactions are listed among possible side effects of lion's mane.[4]
- Memory concerns
- Trials were small and short; in one, gains faded within 4 weeks of stopping.[1]
- Before you start
- Talk to your pharmacist or clinician before adding this supplement, especially if you take prescription medicines, are pregnant or breastfeeding, or have a chronic health condition.[4]
Talk to your pharmacist or clinician before starting a supplement, especially if you take prescription medicines.
Articles about Lion's mane mushroom
Plain-English answers to common questions, built on the evidence above.
Frequently asked questions
Does lion's mane improve memory?
In a 16-week trial of 30 older adults with early memory problems, 3 g/day raised cognitive scores versus placebo, but scores fell after stopping. In healthy young adults, a 28-day pilot found mostly null results.[1][2]
Does lion's mane help focus right away?
Two small studies found faster performance on some tasks 1–2 hours after a single amount (1–1.8 g), alongside null results on others.[2][6]
Does lion's mane help mood or anxiety?
A 4-week trial in 30 women found lower mood-scale (CES-D) and complaint scores within the lion's mane group, but few differences versus placebo. Evidence is too limited to draw conclusions.[3]
Does lion's mane grow nerve cells?
Compounds called hericenones and erinacines stimulate nerve growth factor in laboratory studies. This has not been shown in people.[3][4]
Is lion's mane safe?
No adverse effects appeared on laboratory tests in a 16-week trial. A 2025 review notes stomach discomfort, headache and allergic reactions as possible side effects.[1][4]
What did other trials find?
A 12-week multicenter trial reported better scores on the MMSE but not on two other memory tests.[5]
Sources
- [1]Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial.. Phytother Res, 2009. RCT
- [2]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. pilot-RCT
- [3]Reduction of depression and anxiety by 4 weeks Hericium erinaceus intake.. Biomed Res, 2010. RCT
- [4]Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review.. Front Nutr, 2025. systematic-review
- [5]Improvement of cognitive functions by oral intake of Hericium erinaceus.. Biomed Res, 2019. RCT
- [6]Acute Effects of Naturally Occurring Guayusa Tea and Nordic Lion's Mane Extracts on Cognitive Performance.. Nutrients, 2023. crossover-RCT
What changed
- First draft. Every evidence-row PMID checked with NCBI E-utilities (esummary + efetch abstract) and re-read in an independent adversarial pass.