3 POWERFUL Brain Boosting Mushroom Extracts

Dr. Stengler: Do medicinal mushrooms really improve memory? Right now in the nutraceutical world, mushroom extracts have taken the world by storm. They're very popular, and people are using them to improve memory — people with age-related memory impairment, people with early dementia. But is there good science behind them? In this video, I'm going to go through the science, how to use these mushroom extracts, and which are the best three you can start using right now. What I find with patients is that when you use the right mushrooms at the right extracts and doses, you can notice pronounced effects on memory, cognitive ability, and concentration within 30 to 60 days. Let's get started.

Mushroom extract number one: lion's mane, known scientifically as Hericium erinaceus — also called yamabushitake in Japanese. It grows wild in Japan and parts of Asia and is now cultivated worldwide. Lion's mane has really taken the memory and cognitive health world by storm, and it's one of the most exciting supplements to come along in a long time because of the quality of research behind it.

Lion's mane contains several important compounds. It has polysaccharides known as beta-glucans, which support the immune system and have protective effects on the brain and nervous system. It also contains compounds called hericenones, from the fruiting body of the mushroom, and erinacines, from the mycelium — the root-like component. These compounds have been shown to cross the blood-brain barrier and produce cognitive-improving effects. There are also phenolic compounds with antioxidant effects, and a powerful anti-aging antioxidant called ergothioneine, which I'll discuss more when we get to the golden oyster mushroom.

What makes lion's mane especially unique is that it has been shown to increase nerve growth factor, or NGF — a protein essential for brain cell growth, repair, and protection, and highly relevant for conditions like Alzheimer's and Parkinson's disease. It also reduces nervous system inflammation and protects brain cells from calcium-related damage, which plays a role in how neurons communicate and how degeneration can occur.

Now let's look at the human studies. In a double-blind, placebo-controlled study published in the journal Phytotherapy Research, Japanese adults ages 50 to 80 with mild cognitive impairment took 1,000 milligrams of lion's mane three times a day for four months. Cognitive scores improved significantly at weeks 8, 12, and 16 compared to placebo. One caveat: once people stopped taking lion's mane, scores began to decline — suggesting you need to stay on it to maintain the benefits. Importantly, there were no adverse effects on blood biomarkers, confirming it is very safe.

A second study, published in the journal Nutrients in 2023, looked at the effects of 1,800 milligrams of lion's mane extract in young adults ages 18 to 45. After just a single dose, participants performed faster on cognitive tests, and after 28 days they also reported reduced stress levels — two benefits from one supplement.

In a 12-week randomized placebo-controlled study with an average participant age of 61.8 years, people taking about 3 grams of lion's mane daily showed significant cognitive improvement and prevention of short-term memory deterioration. This is particularly relevant for most of you watching, since age-related memory impairment — where short-term memory, long-term memory, and focus gradually decline — is something lion's mane can meaningfully help with.

Looking at early-stage Alzheimer's disease: a 2020 double-blind study lasting 49 weeks used a lion's mane extract enriched with the compound erinacine A. Results showed improvement in mini-mental state exam scores — a standard clinical tool for screening cognitive difficulties — as well as improvement in brain imaging scores in areas affected by Alzheimer's disease. The placebo group showed decline across several of those same measures. I'm not saying lion's mane cures Alzheimer's — it does not — but the evidence for early-stage benefit is compelling. A systematic review published in 2025 found that lion's mane consistently improved markers related to Alzheimer's disease, as well as symptoms, blood markers, brain structure, and behavior in both animal and human studies.

Mushroom extract number two: reishi, known scientifically as Ganoderma lucidum, and as lingzhi in China. It's been used for thousands of years and carries the nickname "mushroom of immortality" for its health-promoting and anti-aging properties. Researchers have identified over 432 bioactive compounds in reishi, including over 200 types of polysaccharides, over 380 triterpenoids, and over 30 sterols and steroidal compounds. These work through multiple mechanisms in the brain — including anti-amyloid effects, reducing the plaques associated with Alzheimer's disease, and improving acetylcholine levels, the neurotransmitter that declines in Alzheimer's and other memory conditions. Reishi also has anti-inflammatory and antioxidant effects.

In a study published in the Journal of Dementia and Geriatric Cognitive Disorders, 48 people with Alzheimer's disease were divided into two groups: one took the common Alzheimer's drug memantine at 20 milligrams per day, while the other took that drug plus 3,000 milligrams of reishi extract daily for six weeks. The reishi group had better cognitive scores and improved quality of life with no adverse effects compared to those taking the drug alone. If you or someone you know is taking memantine, it's worth talking to your neurologist about adding reishi extract.

In another study of 123 people with Alzheimer's disease, published in the Journal of Medicinal Food, participants took 1,800 milligrams of reishi extract three times a day for eight weeks. Results showed significant reduction in fatigue and improvement in cognitive function, with no toxicity and no problems with liver or kidney function.

A 2024 review in Biomedicine & Pharmacotherapy summarized reishi's effects as: neuroprotective, anti-amyloid, antioxidant, immune-modulating, and acetylcholine-preserving. The reviewers stated that reishi may help slow Alzheimer's progression.

Mushroom extract number three: golden oyster mushroom. This one you may not be familiar with. It's popular in Asian medicine, and what makes it unique is that it's very rich in a sulfur-based amino acid called ergothioneine — an amino acid the human body cannot produce on its own. This matters because research shows it has quite a pronounced effect on the brain. Golden oyster mushroom also contains flavonoids with anti-inflammatory properties, carotenoids with antioxidant effects, beta-glucans for immune support, and prebiotics.

What's particularly unique about ergothioneine is that it can cross the blood-brain barrier. It protects mitochondria — the energy-producing structures in our cells — which is critical for all organs, especially the brain. It protects neurons from oxidative stress damage, supports anti-aging pathways, and appears to delay degeneration of the brain and nervous system.

Americans consume very little ergothioneine — about 1.1 milligrams per day on average, compared to about 4.6 milligrams per day in Europe. Some researchers believe this disparity may contribute to America's higher rates of chronic brain disease.

In a 2024 study published in the Journal of Alzheimer's Disease, 19 people ages 60 and older with mild cognitive impairment took 25 milligrams of ergothioneine capsules three times a week for one year. Results showed improved learning ability, stable levels of brain degeneration markers, and no safety concerns.

In another study published in Free Radical Biology and Medicine in 2022, 470 elderly patients were followed over five years. Those with lower ergothioneine levels had worse memory, faster functional decline, and greater brain atrophy on scans — the lower the levels, the more degeneration occurred.

A cross-sectional study of 496 people comparing healthy individuals to those with cognitive impairment and dementia, including Alzheimer's disease, found that blood levels of ergothioneine were lowest in those with dementia and correlated with white matter damage, brain shrinkage, and disease severity.

So to summarize: these are three powerful mushroom extracts. With a good quality product at the right dose and concentration, multiple studies demonstrate clear benefits to the brain. They don't just help with cognitive function and memory — they work at the root level of why the brain degenerates, and they support factors involved in brain regeneration. I use these with my patients regularly. If you have cognitive concerns or a family history of cognitive problems, look into these three mushroom extracts. Very powerful, very well researched, and very safe. For more videos on cognitive health and memory, see the other videos on my YouTube channel.

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