“Lion's mane mushroom improves memory and focus.”
Lion's mane has not been shown to improve memory or focus in healthy people; small trials found only a few scattered effects on single tests.
Lion's mane is not a proven way to sharpen memory or focus. The few positive results are small, come from tiny studies, and are strongest in older adults who already have memory problems, so a healthy person should not expect a noticeable change.
Save your money for now: lion's mane is unlikely to make a noticeable difference to a healthy memory or focus.
Safety note: Stomach discomfort, headache and allergic reactions such as skin rash have been reported with lion's mane supplements. Stop taking it if you get a rash or other allergic reaction.
Talk to a healthcare professional if: your memory or focus problems are new, getting worse, or getting in the way of daily life.
A handful of small, short trials found a few scattered gains on single tests, while overall memory and thinking scores in healthy adults did not change. The trials are tiny, used different products, and several had ties to companies selling lion's mane.
Lion's mane has not been shown to improve memory or focus in healthy people; small trials found only a few scattered effects on single tests. In a 2023 trial of 41 healthy adults aged 18 to 45, one dose made people faster on one attention test but worse at recalling a word list, and 28 days of use did not clearly improve memory or thinking. In a 2025 trial of 18 healthy young adults, one dose did not improve overall thinking or mood.
The strongest signal is in older adults with mild memory problems. In a 2009 Japanese trial of 30 adults aged 50 to 80 with mild cognitive impairment, scores on a thinking test rose more with lion's mane than with placebo over 16 weeks, then fell after people stopped taking it. A 2025 review of the human studies found five small randomized trials and three pilot studies; in the two studies it could combine, scores on a 30-point memory and thinking test rose about 1 point. A 2026 trial of 109 adults aged 40 to 75 who felt their thinking had slipped found a gain on one of six computer tasks over 8 weeks, with no change in overall scores; it was paid for by a company that sells lion's mane and has not been peer reviewed. Much of the interest in lion's mane comes from animal and lab studies.
- 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;15(22):4842. DOI: 10.3390/nu15224842. PMID: 38004235
- Surendran G, Saye J, Binti Mohd Jalil S, et al. 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. Frontiers in Nutrition. 2025;12:1405796. DOI: 10.3389/fnut.2025.1405796. PMID: 40276537
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- Daoust J, Farrar S, Grant A, Erfe M, Oliver P, Luna V, Moos J, Craft N. A randomized, double-blind, placebo-controlled study evaluating the impact of Hericium erinaceus (Lion's Mane) on cognitive performance and subjective wellbeing. medRxiv preprint, posted 17 April 2026. DOI: 10.64898/2026.04.13.26350781