Lion's mane mushroom and perceived stress: grade C

Limited evidence. Direction: No effect.

C LimitedIndustry-fundedSubjective outcome onlyShort-term only

Educational guidance, not medical advice

Why this grade

Rubric condition met: C: small or pilot studies with within-group or uncontrolled signals; the largest controlled trial did not report lion's mane alone beating placebo

In healthy young adults, 28 days of 1.8 g a day gave only a non-significant trend towards lower stress (p = 0.051). In 84 young women with stress or anxiety, a lion's mane and reishi blend lowered the primary anxiety score relative to lion's mane alone, and all groups including placebo improved. Lower mood-questionnaire scores were reported within the lion's mane group in a 4-week trial in 30 women and in an uncontrolled 8-week study in a clinical population whose participants were also on a low-calorie diet, so supplement and diet effects cannot be separated.

How we grade evidence

Studies this grade rests on

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

Study	Year	Design	Participants	Result
Nagano 2010	2010	RCT	30	result not recorded
Vigna 2019	2019	uncontrolled pilot study (no placebo group), 8 weeks	77	result not recorded
Docherty 2023	2023	RCT	41	result not recorded
Smith 2026	2026	RCT	84	result not recorded

Hericium erinaceus Improves Mood and Sleep Disorders in Patients Affected by Overweight or Obesity: Could Circulating Pro-BDNF and BDNF Be Potential Biomarkers?

Vigna L, Morelli F, Agnelli GM. 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. PMID 31118969

Result not recorded

Design: Uncontrolled pilot study (no placebo group), 8 weeks
Sample: n = 77
Population: Adults with overweight or obesity and a mood or sleep disorder or binge eating, on a low-calorie diet (clinical population)
Funding: Italian Ministry of Education, University and Research; University of Pavia (Crossref); supplement provided by A.V.D. Reform s.r.l.

Reduction of depression and anxiety by 4 weeks Hericium erinaceus intake.

Nagano M, Shimizu K, Kondo R. Reduction of depression and anxiety by 4 weeks Hericium erinaceus intake Biomed Res, 2010. PMID 20834180

Result not recorded

Design: Randomized, placebo-controlled trial (4 weeks)
Sample: n = 30
Population: Women, studied for menopausal symptoms, mood and sleep quality
Funding: not stated

The effects of four-week supplementation of Lion's mane and a Lion's mane and Reishi blend on prioritised mood and wellbeing measures in young women.

Smith EF, Docherty S. The effects of four-week supplementation of Lion's mane and a Lion's mane and Reishi blend on prioritised mood and wellbeing measures in young women Front Nutr, 2026. PMID 42978868

Result not recorded

Design: Randomized, double-blind, placebo-controlled three-arm parallel trial (28 days)
Sample: n = 84
Population: Women aged 18-26 experiencing subjective stress and/or anxiety
Funding: Internal funding from Northumbria University; investigational products provided by Sempera Organics

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.

Docherty S, Doughty FL, Smith EF. 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. PMID 38004235

Result not recorded

Design: Randomized, double-blind, placebo-controlled parallel-group pilot trial (acute and 28-day)
Sample: n = 41
Population: Healthy adults aged 18-45
Funding: No external funding; investigational product provided by Sempera Organics (manufacturer), which had no role in design, analysis or writing

Search and history

Search (November 11, 2026): (Hericium erinaceus[tiab] OR "lion's mane"[tiab]) AND (mood[tiab] OR stress[tiab] OR depress*[tiab] OR anxiety[tiab] OR sleep[tiab]) AND (randomized controlled trial[pt] OR clinical trial[pt] OR trial[ti])

November 11, 2026 Graded C (proposed): Proposed in the monograph draft
November 12, 2026 C to C (proposed): Editor review ed-2026-11-11: C kept, direction changed from benefit to none: no controlled trial showed lion's mane alone beating placebo; industry-funded added because 3 of 4 studies used manufacturer-donated product (policy 3.3).
November 13, 2026 C to C (approved): Editor sign-off November 13, 2026: grade matches the editor-approved final page