Skip to content
Deals

Lion's mane mushroom and global cognition: grade C

Limited evidence. Direction: Benefit.

C LimitedIndustry-funded

Educational guidance, not medical advice

Why this grade

Rubric condition met: C: small RCTs whose positive results come from older adults and clinical populations, extrapolated to healthy adults

Three small placebo-controlled trials (30 adults with mild cognitive impairment, 31 healthy adults around 60, 49 with mild Alzheimer's disease) reported better scores on cognitive screening scales. In the trial with mild cognitive impairment, scores fell within 4 weeks of stopping. Two of the three trials were run by or with staff of mushroom companies. The 2025 systematic review could not pool the trials. The positive screening-scale results come from older and clinical populations; an 18-person single-dose trial in healthy younger adults, with authors employed by a company selling lion's mane, found no significant effect on composite global cognition.

How we grade evidence

Studies this grade rests on

EffectMixedNo effectSize shows participants (n)200520102015202020252030Meta-analysisRCTCrossover RCTLi 2020, 2020: RCT, n = 49, result not recordedSaitsu 2019, 2019: RCT, n = 31, result not recordedMori 2009, 2009: RCT, n = 30, result not recordedSurendran 2025, 2025: crossover RCT, n = 18, result not recordedMenon 2025, 2025: meta-analysis, n not recorded, result not recorded
each study this grade rests on, by publication year and design. Solid: effect versus the comparator; half-filled: mixed; hollow: no effect; dashed: result not recorded yet. Larger marks had more participants.
Show the numbers
StudyYearDesignParticipantsResult
Mori 20092009RCT30result not recorded
Saitsu 20192019RCT31result not recorded
Li 20202020RCT49result not recorded
Surendran 20252025crossover RCT18result not recorded
Menon 20252025meta-analysisnot recordedresult not recorded

Acute effects of a standardised extract of Hericium erinaceus (Lion's Mane mushroom) on cognition and mood in healthy younger adults: a double-blind randomised placebo-controlled study.

Surendran G, Saye J, Binti Mohd Jalil S. Acute effects of a standardised extract of Hericium erinaceus (Lion's Mane mushroom) on cognition and mood in healthy younger adults: a double-blind randomised placebo-controlled study Front Nutr, 2025. PMID 40276537

Result not recorded
Design
Randomized, double-blind, placebo-controlled crossover trial (single dose)
Sample
n = 18
Population
Healthy adults aged 18-35
Funding
Beyond Alcohol Ltd. (Three Spirit Drinks) contributed towards the publication fee

Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review.

Menon A, Jalal A, Arshad Z. Benefits, side effects, and uses of Hericium erinaceus as a supplement: a systematic review Front Nutr, 2025. PMID 40959699

Result not recorded
Design
Systematic review (5 RCTs, 3 pilot clinical trials, laboratory studies, 1 case report); no meta-analysis performed
Population
Human studies in people with and without dementia, plus laboratory studies
Funding
Article processing charges covered by Mohammed Bin Rashid University of Medicine and Health Sciences

Prevention of Early Alzheimer's Disease by Erinacine A-Enriched Hericium erinaceus Mycelia Pilot Double-Blind Placebo-Controlled Study.

Li IC, Chang HH, Lin CH. Prevention of Early Alzheimer's Disease by Erinacine A-Enriched Hericium erinaceus Mycelia Pilot Double-Blind Placebo-Controlled Study Front Aging Neurosci, 2020. PMID 32581767

Result not recorded
Design
Pilot randomized, double-blind, placebo-controlled trial (49 weeks)
Sample
n = 49
Population
Adults with diagnosed mild Alzheimer's disease (clinical population)
Funding
Grape King Bio Ltd. (salaries of five authors and research materials, per the paper's conflict-of-interest statement)

Improvement of cognitive functions by oral intake of Hericium erinaceus.

Saitsu Y, Nishide A, Kikushima K. Improvement of cognitive functions by oral intake of Hericium erinaceus Biomed Res, 2019. PMID 31413233

Result not recorded
Design
Randomized, double-blind, placebo-controlled parallel-group trial
Sample
n = 31
Population
Healthy Japanese adults aged about 50 and over (mean age about 61, per S4 table)
Funding
not stated

Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial.

Mori K, Inatomi S, Ouchi K. Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial Phytother Res, 2009. PMID 18844328

Result not recorded
Design
Randomized, double-blind, placebo-controlled parallel-group trial
Sample
n = 30
Population
Japanese adults aged 50-80 with diagnosed mild cognitive impairment (clinical population)
Funding
not stated

Search and history

Search (): (Hericium erinaceus[tiab] OR "lion's mane"[tiab]) AND (cognit*[tiab] OR memory[tiab]) AND (randomized controlled trial[pt] OR clinical trial[pt])

  • Graded C (proposed): Proposed in the monograph draft
  • C to C (approved): Editor sign-off November 13, 2026: grade matches the editor-approved final page