Does Lion’s Mane Help With Brain Fog? What Every Human Trial Actually Measured, and What a Tincture Can Do

Lion’s Mane (Hericium erinaceus, yamabushitake in Japanese, hóu tóu gū — “monkey head mushroom” — in Chinese) is the medicinal mushroom sold more than any other “for brain fog”, and the state of the human research, said all the way to the end, is this: no trial has ever recruited people for brain fog or measured brain fog as an outcome.

What exists: one trial in 30 older adults with diagnosed mild cognitive impairment, in which scores rose over 16 weeks and fell back a month after stopping; a 12-week trial in healthy adults in which one of three tests moved; and three single-dose trials in healthy young adults that found faster reaction times on a few tasks, no difference in how clear-headed people felt, and in one case nothing at all. A four-week trial at 10 g a day found nothing. Below: every one of those trials with size, dose and result; what medicine knows about brain fog itself and its causes; what happened when someone tried to isolate the famous “NGF molecule”; and a plain statement of what a 1.4 ml daily dose of fruiting-body extract can and cannot do.

Does Lion’s Mane help with brain fog?

In humans it has been shown to raise cognition scores in older adults with mild cognitive impairment for as long as they keep taking it, and to shorten reaction times on some computerised tasks one to two hours after a single dose. It has never been tested in people whose complaint is brain fog, no trial has measured “fog” or “clarity” as a primary outcome, and in the trials that did ask participants how they felt, they felt no different from placebo. That is a narrower answer than “the smart mushroom”, and it is the one the trials support.

The table lists every human study we found in PubMed in which Lion’s Mane was taken by mouth and a cognitive or psychological outcome was recorded. The “what it does not mean” column is where the distance between a search-result sentence and a research finding lives.

Three things stand out. First, the only clear effect — the 2009 trial — belongs to people who already had a diagnosed decline, and it vanished when they stopped. Second, in every trial in healthy adults that asked participants how they felt, they felt no different from placebo; what moved was the measuring instrument, and sometimes not even that. Third, the 2025 systematic review that pooled the clinical research found five randomised trials and three pilots, and when it combined the only two that reported MMSE it arrived at a weighted increase of 1.17 points — on a 30-point scale. A broad 2024 review of 34 human studies on mushrooms and the brain concluded that the observational studies were positive and “the results obtained from intervention studies were mixed”. The original answer this article gave in July 2026 is preserved below; the table above is the reason we stand behind it.

What is brain fog, exactly — and what does research measure when it studies it?

Brain fog is not a diagnosis but a word people use for very different experiences, which is why you cannot “test a mushroom for brain fog” without first deciding what to measure. When researchers in Edinburgh analysed 717 Reddit posts that used the term, 141 first-person descriptions spoke of forgetfulness (51), difficulty concentrating (43), dissociative feelings of detachment (34), slowness and excessive cognitive effort (26), communication difficulties (22), “fuzziness” or pressure (10) and fatigue (9). Half the posts were in forums about illness. The neurologist who led the study wrote for clinicians in 2025 that “at least some of the time we are likely to be getting it wrong” about what a patient means.

The consequence for our question is simple: when someone says “fog”, they sometimes mean memory, sometimes attention, sometimes detachment, sometimes fatigue — and the Lion’s Mane trials measured general cognition scales (MMSE, HDS-R), reaction times (Stroop, N-Back, Go/No-go) and mood questionnaires. None measured detachment or “excessive effort”, which are a central part of what people call fog. When a 2025 study of 793 people after COVID-19 looked for objective markers of fog, it found slower reading and typing, slower reaction times on cognitive tasks and changes in information-processing speed — exactly the kind of measure on which Lion’s Mane showed its small improvements in healthy young adults. That is the only point where the two literatures touch, and it is indirect: the study that measured the marker gave no mushroom, and the studies that gave the mushroom recruited nobody with fog. The article’s original explanation of what fog is stands below; it is right, and only the numbers are new.

What causes brain fog — and why does that matter for a question about a mushroom?

Because each cause has a literature of its own, with numbers of its own, and Lion’s Mane has been tested in none of them. After COVID-19: a meta-analysis of 81 studies found that 32% of people report fatigue and 22% report cognitive impairment 12 or more weeks after the illness (25,268 and 13,232 people respectively). Sleep loss: a single night of 2–6 hours of sleep lengthens reaction times on sustained-attention tasks and increases lapses (44 studies), and a meta-analysis of 70 papers found that lapses in simple attention are the largest single casualty of short-term sleep deprivation. Menopause: longitudinal studies find small but reliable declines in memory performance across the perimenopause, not explained by age alone, and within normal limits for almost all women. Hypothyroidism: a fog described as fatigue, low mood and difficulty with memory and executive function, sometimes predating the diagnosis.

The reason we spell this out on a page that sells a mushroom is that the research on post-COVID fog has already tested interventions — a 2024 systematic review found 17 studies of non-invasive brain stimulation, hyperbaric oxygen, cognitive rehabilitation and a PEA-luteolin supplement — and none of them was a mushroom. We searched ourselves: “Hericium” together with “brain fog” or “COVID” in PubMed returns general reviews of mushrooms and viruses, and zero trials. A Canadian study from 2023 found that women, people who had a relatively mild acute illness, and people with prior mental-health diagnoses were at higher risk of cognitive symptoms eight months after COVID-19, with gradual improvement over 20 months; the 793-person study from 2025 found that at follow-up 82.4% had not remitted. These are numbers a person with fog should know before buying any supplement, because they say the first step is to identify the cause. Our calm, focus and balance page and our mushrooms for sleep page touch the two causes on which indirect mushroom research does exist.

What has actually been studied?

Three forms: dried fruiting-body powder in tablets or capsules (1–3.2 g a day, 12–16 weeks), a single dose of powder or concentrated extract (1–3 g, measured 60–120 minutes later), and food — cookies and muffins with the mushroom baked in (4 weeks, up to 10 g a day). The measures: general cognition scales for older adults, computerised speed and attention tests, and mood and sleep questionnaires. The original version of this article chose three representative trials and explained the chemistry behind them; it is preserved below as written, including its funding disclosure, and the table above completes it to nine.

What did the research find — and what did it not find?

Found: higher cognition scores in older adults with mild cognitive impairment for as long as they kept taking it; one test of three improved after 12 weeks in healthy adults; faster reaction times on a few tasks one to two hours after a single dose in young adults. Not found: any difference from placebo in felt focus or clarity in any trial; any improvement on the composite cognition measure after 3 g of a concentrated extract; anything at all after 10 g a day for a month; and any effect that outlasted stopping. The original analysis of the three trials is preserved below, including its most important point — that improving from a baseline of 29.19 out of 30 is not an improvement anyone can feel.

Is the result in people who already have cognitive decline relevant to someone with fog?

Only indirectly, and that is the distinction supplement sellers erase. The 2009 trial — the source of “a Japanese study showed cognitive improvement” on every sales page — recruited people aged 50–80 diagnosed with mild cognitive impairment, a condition in which a cognition scale can rise because it has somewhere to rise to. The 2020 trial recruited patients with mild Alzheimer’s disease and gave them a mycelium product standardised to erinacine A for 49 weeks. Those two trials are the best human evidence for Lion’s Mane, and both were run in people who do not “have fog” but have a diagnosis, using products — 3 g of powder a day, an enriched mycelium — unlike what is sold for fog.

There is also something important here in the mushroom’s favour: the 2009 Japanese trial is one of the better-run trials in the field — double-blind, placebo-controlled, three measurement points showing a trend, and a post-treatment follow-up showing the effect disappear. The drop after stopping is the most convincing evidence that the effect was real and not noise, and in the same breath it says Lion’s Mane does not “repair” something but acts for as long as it is in the body. The 2025 systematic review pooled the only two studies reporting MMSE — the 2020 Alzheimer’s trial and the 2019 healthy-adult trial — into a weighted gain of 1.17 points out of 30, and called for larger trials. Anyone with a diagnosed cognitive decline should be talking to a neurologist, not a web page; anyone with fog should know that the trial being quoted to them was run on someone else. Our Lion’s Mane and cognitive function page and our Lion’s Mane and memory page go deeper into that literature.

What happens in healthy adults — the full picture?

Four trials in healthy young and middle-aged adults, four thin results: 1.8 g shortened a Stroop task an hour after dosing in 41 young adults, alongside null results the authors themselves caution about; 1 g improved reaction times on two of three tasks against baseline, while participants rated the caffeine tea as the thing that gave them “clarity”; 3 g of a concentrated extract did not move the composite in 18 young adults; and 10 g a day for four weeks moved nothing in 24 students. The 12-week trial in healthy adults moved one test of three.

The pattern matters more than any single trial. When you measure healthy people on sensitive computerised tests, an improvement of a few milliseconds in reaction time can be statistically significant and completely imperceptible — and that is exactly what came out: instruments moved, people did not feel it. The 2023 trial that compared Lion’s Mane to guayusa tea is a lesson in itself, because it showed what people do feel: participants rated the caffeine drink higher on clarity, focus, concentration and productivity than both Lion’s Mane and placebo, and their blood pressure rose with it. Lion’s Mane changed a measure; caffeine changed a feeling. Someone looking to “not feel foggy” is looking for the second, and the research does not supply it. The 10 g trial from 2022 deserves special mention because it is the only one to test a genuinely high dose over time in young adults — and found nothing, on attention or metabolism; it is single-blind and small, but had it been positive it would be quoted on every blog. Our mushrooms for focus page lays out the same trials from the angle of concentration.

Does Lion’s Mane affect concentration and mood — the hint from menopausal women?

Two small trials found better mood, and one of them is the closest human hint to “fog” in the whole literature: in 30 menopausal women who ate Lion’s Mane cookies for four weeks, the “concentration”, “irritation” and “anxiety” items of the complaints questionnaire tended to be lower than placebo, and the “insensitivity” and “palpitation” items were significantly lower. In 77 people with overweight or obesity and a mood or sleep disorder, eight weeks of a supplement reduced depression, anxiety and sleep disorders and raised serum pro-BDNF without changing BDNF — but the abstract reports no placebo group, and all of them were dieting.

Why this is relevant to fog: because much of what people describe as fog — the dissociation, the effort, the fatigue on the Reddit list — is closer to mood and sleep than to memory, and that is exactly where Lion’s Mane has shown signals in human trials, small as they are. The Japanese authors wrote explicitly that their results “suggest a different mechanism from NGF-enhancing action” — in other words, even the researchers who found the effect did not attribute it to the molecule on the bottles. Menopausal women are also the group in which real fog research exists — the small, reliable memory declines of the perimenopause — so that overlap deserves a trial that has not yet been run. Our Lion’s Mane and mood page and our Lion’s Mane, calm and mood page detail these trials; the distinction between mood and cognition matters because it changes what you should write down before testing it on yourself.

Why does everyone talk about NGF — and what did the lab actually find?

Because in 2008 a Japanese group compared ethanol extracts of four edible mushrooms in human brain cells (1321N1 astrocytoma cells), and only Lion’s Mane raised NGF gene expression and protein secretion, while mice fed 5% Lion’s Mane powder for seven days showed more NGF in the hippocampus. What goes uncited: in the same paper, hericenones C, D and E — the compounds that appear on every sales page as “NGF stimulators” — failed to promote NGF expression, and the authors concluded that the active compounds “are not hericenones”. The chemical story is real; the label simply attributes it to the wrong molecule.

Then there is the mycelium question. The second group of compounds, the erinacines, is the one most studied in models of nerve disease — and the fruiting body barely produces it. A 2025 study that measured both the compounds and the expression of the genes that make them found erinacines “generally not detectable” in fruit-body tissue, with production happening in the mycelium and depending heavily on the growth substrate; a 2019 Italian study found erinacine A in the mycelium and hericenones C and D in the fruiting bodies, with the highest content in cultivated fruiting bodies compared with wild ones. That says two honest things: our extract, from fruiting bodies, does not contain erinacines in any meaningful amount, and the hericenones it does contain — we do not measure and do not publish a number for. The animal work itself is interesting: two months of a Lion’s Mane supplement standardised for hericenones and erinacine restored recognition memory in frail aged mice and raised markers of neurogenesis in the hippocampus and cerebellum; in the same research group, healthy mice showed better recognition memory and hippocampal transmission, but zero change in spatial memory. A 2023 review concludes that the field needs “standardization processes for dietary supplements” before efficacy and safety can be discussed. Our Lion’s Mane science page and our fruiting body or mycelium page explain why we would rather prove a measured beta-glucan than tell a story about a molecule that was not measured.

Why doesn’t a measured improvement feel like anything?

Because a computerised test detects a difference of milliseconds, and a person detects a difference in their morning. In the trials in healthy people, the improvements were in reaction times against baseline, within one to two hours, on tasks nobody performs in daily life; the questionnaires about felt focus did not move. In the Edinburgh neurologist’s study, what people call fog includes detachment, effort and fatigue — sensations an N-Back task does not measure at all. The article’s original explanation of the gap is preserved below; it is still the best explanation there is.

How much Lion’s Mane did the trials use — and how much is in a tincture?

Grams of dried powder, versus drops. The 2009 trial gave 3 g a day; the 2019 trial — per the original article below — 3.2 g a day; the 2023 trial in young adults 1.8 g; the single-dose trials 1 and 3 g; the 2022 trial 10 g a day. Our label dose is 1.4 ml of extract a day, about a quarter of a teaspoon. We will not convert that number into grams of powder and we will not tell you that “2 ml equals a trial”, because no such conversion exists — the original version of this page attempted one, and we are correcting it today.

Here is exactly what we do know about our extract, so you decide with the numbers in front of you. It is a triple extraction — water, alcohol and ultrasonic — of fresh Lion’s Mane fruiting bodies that go from harvest to extraction without a drying step, with the alcohol extraction running for seven weeks. The mushroom-to-liquid ratio is 1:2 in fresh mushroom, meaning about 25 g of fresh mushroom went into each 50 ml bottle — and fresh mushroom is mostly water, so 25 g fresh is not 25 g of powder, and a fresh 1:2 is not a dried 1:2; our extract ratios page explains why the two ratios cannot be compared, and our fresh vs dried page explains why we chose not to dry anyway. The beta-glucan content of the dry extract is 23.93%, measured at TÜV Austria, with the report published on our lab-testing page, and alpha-glucan — the starch that betrays grain-grown mycelium — was not detected. What we do not measure is hericenone content, and we will not convert the beta-glucan percentage into a per-drop figure, because that requires an extraction-yield figure we have not verified — our beta-glucan page explains why. And beta-glucan, to be clear, is a measure of the extract’s quality and honesty, not the molecule the cognition studies point to. Our dosage guide sets the trial doses beside the bottle; the article’s original dosing paragraphs are preserved below with one correction: the original sentence stated the ratio on a dry-weight basis, and our ratios are stated in fresh mushroom — so the two comparison sentences derived from that error (“2 ml matches the trial”, “3.2 g corresponds to 6.4 ml”) have been removed and not replaced, because the correct number does not exist.

What Lion’s Mane does not do (the honesty section)

It does not treat brain fog, because no trial tested that; it does not replace working out the cause — COVID-19, sleep, thyroid, iron, menopause — each of which has its own literature and zero mushroom trials; it does not give a feeling of clarity within an hour, because in the only trial that compared, that feeling came from caffeine; and it does not leave an effect behind after you stop, according to the only trial that measured. The article’s original honesty section is preserved below because it was right, and we have only added the four boundaries the table sharpened.

Who should not take Lion’s Mane for brain fog?

Anyone whose fog is new, persistent or worsening and has not yet been assessed by a doctor — because the first step is to identify a cause, not to cover it; anyone with a mushroom allergy or asthma — a 2003 case report described a 63-year-old man who developed acute respiratory distress syndrome four months after starting a Lion’s Mane extract, with a positive lymphocyte stimulation test, and recovered; anyone on blood thinners or diabetes medication, as a precaution based on laboratory and animal work rather than a human trial; and by our own rule rather than any evidence of harm — women who are pregnant or nursing and anyone under 18, because our extracts contain alcohol and there is no safety research in those groups.

In the controlled trials the profile is quiet: the laboratory tests in the 2009 trial showed nothing, four people dropped out of the 49-week trial for abdominal discomfort, nausea and rash, and the 2025 systematic review lists stomach discomfort, headache and allergic reactions as the “commonly unreported” side effects. Our extract is 32–33% alcohol by volume, and 1.4 ml of it is a little under half a millilitre of alcohol — a number that matters to anyone avoiding alcohol for any reason. Our Lion’s Mane side effects page holds the full case-report table, and our drug interactions, pregnancy and breastfeeding and children pages hold the detail.

How do you use a Lion’s Mane extract for brain fog?

Daily, at the same time, for at least four to eight weeks as in the trials, with a note of what you want to change written down before you start — and, before that, a conversation with a doctor if the fog is new or persistent. The article’s original instructions are preserved below; the “morning or midday” logic is convenience, not evidence — no trial compared times of day, and our timing and stacking guide explains why consistency matters more than timing. Our powder, capsules or tincture page explains why we make a liquid, and also why the “absorbed under the tongue” claim does not hold for polysaccharides.

How long until you see a change — and how do you test it on yourself?

The only trial with a clear result saw a first difference at week 8 and the largest at week 16; the trials in healthy people saw changes on an instrument within one to two hours that nobody felt; the 28-day trial saw a trend in stress that did not reach significance. Nothing in the human literature supports a feeling of “fog lifting” within days. A 50 ml bottle at 1.4 ml a day lasts about 35 days, and that is a fair first window — shorter than the Japanese trial, longer than any trial in healthy adults.

So the fair test is the one we propose on our how long do medicinal mushrooms take to work page: before you start, write down what exactly you call “fog” — trouble finding words? slowness in the morning? losing concentration after lunch? — and how many times a week it happens. Give it a month, and compare lists rather than impressions; remember that the placebo in the 2023 trial improved “focus and concentration” after an hour, so even the feeling that something is working is a data point to check. And if you changed sleep, caffeine or workload at the same time, the list will tell you what actually changed. If after a bottle nothing has moved, the 100-day trial exists so you can stop without losing money, and we would rather you did that than kept buying on hope.

When is brain fog a reason to see a doctor?

When it lasts more than a few weeks, when it appeared after an illness, when it interferes with work or driving, when it comes with fatigue, weight change, insomnia or low mood, and when it is new in someone over 50. The article’s original list — preserved below — gives the six causes a blood test and a conversation can rule out; after the research of recent years we would add COVID-19 to it explicitly, because 22% of people report cognitive impairment 12 or more weeks after the illness and most have never been assessed for it.

What does the research still not know?

Whether Lion’s Mane changes anything in people whose complaint is brain fog — because no trial recruited them. Whether it helps after COVID-19, in the menopause or under sleep loss — the common causes of fog — because no trial was run in those groups. Whether the reaction-time improvement in healthy people translates into anything a person feels after a month, because the longer trials in healthy people did not find it. Which compound is responsible — when hericenones failed the NGF test and erinacines live in the mycelium — and therefore which form of product is even the right one. And whether there is a dose: 1.8 g moved a Stroop task, 10 g moved nothing.

The reviews agree. The 2025 systematic review ended with a call for larger trials; the 2024 review of 34 human studies ended with “further acute and chronic human intervention studies are needed, using adequate sample sizes, employing appropriately sensitive neurocognitive tests”; and the 2023 review of neuroprotection with “standardization processes for dietary supplements … are essential”. What we can measure, we measure: the beta-glucan content of the finished extract, its heavy-metal, pesticide and PAH results, and the fresh-mushroom-to-liquid ratio. “Clears brain fog” is not something you can put on a certificate. A lab result is, which is why the proof band on this page shows a percentage with a report number and not a sentence about NGF. Our how to read a COA page explains what to look for on such a certificate from any producer.

The bottom line

Lion’s Mane has one solid human result — higher cognition scores in 30 older adults with mild cognitive impairment over 16 weeks, gone a month after stopping — a handful of trials in healthy people that moved instruments rather than feelings, two small trials with mood signals, and one 10 g-a-day trial that found nothing. “Brain fog” has never been measured. The NGF story belongs to different compounds than the ones on the bottles, and the erinacines belong to the mycelium. A tincture delivers material from a different source than the trials’ powder, and we do not claim otherwise. If you have fog — find the cause first, because COVID-19, sleep, the thyroid and the menopause have numbers of their own and no mushroom has been tested against them. If you want the extract for the cognition and mood evidence around it, choose one from fruiting bodies with beta-glucan measured on the finished product, take it daily for a month with a list you wrote beforehand, and talk to a doctor before starting if you take any medication. The original closing of the article, on the line between a supplement and a diagnosis, is preserved below — it was the truest part of the previous version.

Frequently asked questions about Lion’s Mane and brain fog

Scientific sources (peer-reviewed)

1. Lion’s Mane powder in 30 older adults with mild cognitive impairment, 3 g a day, 16 weeks — scores above placebo at weeks 8–16, a drop 4 weeks after stopping. Mori K, Inatomi S, Ouchi K, et al. Phytotherapy Research, 2009. View on PubMed
2. Fruiting-body supplement in adults, 12 weeks — only the MMSE of three tests improved. Saitsu Y, Nishide A, Kikushima K, et al. Biomedical Research, 2019. View on PubMed
3. 1.8 g in 41 healthy young adults — faster Stroop at 60 minutes, a trend to lower stress at 28 days, alongside null findings; pilot. Docherty S, Doughty FL, Smith EF. Nutrients, 2023. View on PubMed
4. 1 g Lion’s Mane vs guayusa tea vs placebo, single dose — reaction times vs baseline; guayusa rated higher for clarity and focus. La Monica MB, Raub B, Ziegenfuss EJ, et al. Nutrients, 2023. View on PubMed
5. 3 g of a 10:1 extract in 18 healthy young adults, single dose — no effect on the composite cognition and mood measures. Surendran G, Saye J, Binti Mohd Jalil S, et al. Frontiers in Nutrition, 2025. View on PubMed
6. 10 g a day in 24 college students, 4 weeks — no effect on cognition or metabolic flexibility. Grozier CD, Alves VA, Killen LG, et al. International Journal of Exercise Science, 2022. View on PubMed
7. Lion’s Mane cookies in 30 women, 4 weeks — lower depression and complaint scores; “concentration” and “anxiety” tended to be lower than placebo. Nagano M, Shimizu K, Kondo R, et al. Biomedical Research, 2010. View on PubMed
8. 8 weeks in 77 people with overweight and a mood or sleep disorder — depression, anxiety and sleep improved; pro-BDNF rose. Vigna L, Morelli F, Agnelli GM, et al. Evidence-Based Complementary and Alternative Medicine, 2019. View on PubMed
9. Erinacine A-enriched mycelium in mild Alzheimer’s, 49 weeks — better MMSE and daily functioning than placebo; 4 dropouts. Li IC, Chang HH, Lin CH, et al. Frontiers in Aging Neuroscience, 2020. View on PubMed
10. Systematic review of the clinical research on Lion’s Mane — 5 randomised trials and 3 pilots; MMSE +1.17 weighted; side effects. Menon A, Jalal A, Arshad Z, et al. Frontiers in Nutrition, 2025. View on PubMed
11. 34 human studies on mushrooms, mood and cognition — observational studies positive, “intervention results mixed”; review. Cha S, Bell L, Shukitt-Hale B, et al. Neuroscience & Biobehavioral Reviews, 2024. View on PubMed
12. What is brain fog — analysis of 717 first-person accounts: forgetfulness, difficulty concentrating, detachment, slowness and effort, fatigue. McWhirter L, Smyth H, Hoeritzauer I, et al. Journal of Neurology, Neurosurgery & Psychiatry, 2023. View on PubMed
13. Brain fog in the neurology clinic — the range of experiences the term covers and how to ask; review. McWhirter L. Practical Neurology, 2025. View on PubMed
14. Menopause and brain fog — small but reliable memory declines in perimenopause, within normal limits for almost all women. Maki PM, Jaff NG. Menopause, 2024. View on PubMed
15. Brain fog in hypothyroidism — fatigue, low mood, memory and executive function; review. Samuels MH, Bernstein LJ. Thyroid, 2022. View on PubMed
16. Fatigue and cognitive impairment 12 or more weeks after COVID-19 — 32% and 22%; meta-analysis of 81 studies. Ceban F, Ling S, Lui LMW, et al. Brain, Behavior, and Immunity, 2022. View on PubMed
17. Long-COVID brain fog — women, milder illness and prior mental-health diagnoses as risk factors; gradual improvement over 20 months. Lam GY, Damant RW, Ferrara G, et al. Journal of Neurology, 2023. View on PubMed
18. 793 people after COVID-19 — markers of fog: slower reading, typing and reaction times; 82.4% had not remitted at follow-up. Staggs H, Furst A, Mills-Finnerty C. Psychiatry Research, 2025. View on PubMed
19. Interventions for long-COVID brain fog — 17 studies: brain stimulation, hyperbaric oxygen, rehabilitation, PEA-luteolin; systematic review. Gorenshtein A, Liba T, Leibovitch L, et al. Neurological Sciences, 2024. View on PubMed
20. Short-term sleep deprivation and cognition — 70 papers; lapses in simple attention the largest effect; meta-analysis. Lim J, Dinges DF. Psychological Bulletin, 2010. View on PubMed
21. One night of 2–6 hours of sleep — sleepiness, reaction times and lapses in sustained attention; 44 studies; meta-analysis. Wüst LN, Capdevila NC, Lane LT, et al. Sleep Medicine Reviews, 2024. View on PubMed
22. Lion’s Mane extract induces NGF in human brain cells and mouse hippocampus — hericenones C, D and E did not. Mori K, Obara Y, Hirota M, et al. Biological & Pharmaceutical Bulletin, 2008. View on PubMed
23. Erinacines are produced in the mycelium and are “generally not detectable” in the fruit body; substrate changes the content. Doar E, Meyer KW, Bair ZJ, et al. Fungal Biology and Biotechnology, 2025. View on PubMed
24. Erinacine A in mycelium, hericenones C and D in fruiting bodies — higher content in cultivated than wild fruiting bodies. Corana F, Cesaroni V, Mannucci B, et al. Molecules, 2019. View on PubMed
25. Two months of Lion’s Mane in frail aged mice — recognition memory restored, neurogenesis in hippocampus and cerebellum. Ratto D, Corana F, Mannucci B, et al. Nutrients, 2019. View on PubMed
26. Lion’s Mane in healthy mice — more locomotor activity, no effect on spatial memory. Rossi P, Cesaroni V, Brandalise F, et al. International Journal of Medicinal Mushrooms, 2018. View on PubMed
27. Neuroprotective effects of Lion’s Mane — review: “standardization processes for dietary supplements are essential”. Szućko-Kociuba I, Trzeciak-Ryczek A, Kupnicka P, et al. International Journal of Molecular Sciences, 2023. View on PubMed
28. Acute respiratory distress syndrome linked to a Lion’s Mane extract — case report, a 63-year-old man, recovered. Nakatsugawa M, Takahashi H, Takezawa C, et al. Internal Medicine, 2003. View on PubMed

Further reading on this site: Lion’s Mane science · Lion’s Mane and memory · Lion’s Mane and cognitive function · the research hub, filtered for cognition · Lion’s Mane for brain fog — the extract page · the complete guide to functional mushrooms · all solutions by goal · mushrooms for focus · Lion’s Mane and mood · Reishi for stress and anxiety · Lion’s Mane side effects · Lion’s Mane dosage · fresh vs dried mushroom extract · fruiting body or mycelium · how to read a COA.

These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease. This page is an educational review of published research and is not medical advice. Consult a physician before using any dietary supplement, especially if you take medication, are pregnant or nursing, or have a diagnosed medical or psychiatric condition.