Nootropic Mushrooms: What the Research Actually Shows

What the evidence shows

Lion’s mane has the clearest direct cognition trial evidence, but the positive findings come from small studies and are not consistent across tests or populations.
A trial in older adults with mild cognitive impairment reported improved cognitive scale scores during lion’s mane use; it does not establish dementia prevention or lasting benefit.
A 2022 study in college-age adults and a small acute trial in healthy young adults did not show an overall cognitive benefit from lion’s mane.
The cited reishi-cordyceps trial tested a combination in healthy young adults and found no significant differences across cognitive domains.
Different mushroom parts, extracts and formulations are not interchangeable, and animal or laboratory findings do not establish effects in people.

What counts as evidence for a mushroom nootropic?

A human cognition trial tests whether a mushroom preparation changes measured cognitive performance in people. That is different from laboratory or animal research on compounds such as erinacines, hericenones or cordycepin. Those findings can suggest questions for human research, but they do not establish that a supplement improves memory, focus or brain health in people.

The studies also test particular preparations: whole dried mushroom, fruiting-body extract, mycelium, or blends. Their results cannot automatically be applied to other products, because mushroom part, extraction and composition can differ. Even a well-designed trial of one preparation would not establish effects for every supplement sold under the same mushroom name.

Lion’s mane: a promising signal, with important limits

Lion’s mane (Hericium erinaceus) has the most direct cognition research among these three mushrooms. In a double-blind, placebo-controlled trial, 30 Japanese adults aged 50–80 with mild cognitive impairment were randomized to lion’s mane or placebo for 16 weeks. The lion’s mane group’s cognitive scale scores improved during the study; scores fell after the supplement was stopped. The small sample and limited follow-up mean this is an early finding, not evidence that lion’s mane prevents dementia or produces lasting change. (Mori et al., 2009.)

A later randomized, double-blind, placebo-controlled study of lion’s mane fruiting-body supplements over 12 weeks reported improvement on the Mini-Mental State Examination, but not on the other two cognitive tests used. That pattern matters: one positive measure among several does not establish a broad cognitive effect. The available abstract does not give enough detail to judge how well the result applies to other groups or preparations. (Saitsu et al., 2019.)

Healthy adults: results are mixed

Trials in healthy adults have not established a reliable cognitive benefit. A 2022 placebo-controlled study tested lion’s mane in college-age adults over four weeks and found no significant change in the cognitive measure used. A small acute, double-blind crossover study in 18 healthy adults aged 18–35 likewise found no significant overall effect on composite cognition or mood. Some individual task results differed, but the findings pointed in conflicting directions, so they need replication. (Grozier et al., 2022; acute lion’s mane trial, 2025.)

These studies address short-term performance in healthy, relatively young people. They do not answer whether a particular lion’s mane preparation could have a different effect in older adults or people with cognitive impairment. Nor do small studies settle whether any change is large enough to matter in daily life.

Reishi and cordyceps: the cognition evidence is thinner

A randomized trial studied a commercial supplement combining Ophiocordyceps sinensis (cordyceps) and Ganoderma lucidum (reishi) in 96 healthy physical-education students, with a mean age of about 26. Participants were assigned to two supplement groups or placebo for 30 days. The study found no significant differences between groups across global cognition, memory, executive function, attention, processing speed and other assessed domains. (Tsuk et al., 2017.)

Because the product combined both mushrooms, the result cannot show what reishi or cordyceps would do alone. It also studied healthy young adults, not older people or people with cognitive impairment. Based on this trial, the human cognition evidence for either mushroom is limited; claims that either reliably sharpens memory or focus go beyond what it tested.

What remains uncertain

The studies differ in participants, mushroom species, mushroom part, extraction and cognitive tests. That makes comparisons difficult and limits how confidently one result can be generalized. Most trials are also small or short, and a statistically detectable change on one test does not by itself show a meaningful day-to-day benefit.

More research would need to test clearly described preparations in larger groups, use consistent and appropriate cognitive measures, and follow participants long enough to see whether any effects persist. For now, lion’s mane has preliminary human signals alongside null and mixed findings. For reishi and cordyceps, the direct cognition evidence described here comes from a combination product trial that found no benefit. Animal mechanisms and traditional use do not resolve these uncertainties.

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About this article

NootroWorld publishes research summaries, not medical advice. This article describes what studies have and have not established; it does not tell you what to take. Supplements can interact with medication, pregnancy and existing health conditions, and study populations often differ from your own situation. Discuss any personal decision with a qualified healthcare professional.