Could Lion’s Mane Mushroom Become a Treatment for Alzheimer’s and Mild Cognitive Impairment?

by Eva Coles MS, RDNNutrition
Lion's mane mushroom growing on a tree

Lion’s mane is an edible medicinal mushroom that has been used in traditional chinese medicine for millennia to treat various ailments including cognitive impairment. In recent years, lion’s mane gained popularity in the mainstream as a brain supplement believed to improve cognitive function [1]. Emerging evidence is suggesting that supplementation with lion’s mane may even treat or protect against Alzheimer’s Disease. 

This post will cover the evidence that exists surrounding benefits for cognition from using lion’s mane, suggested uses, side effects, and safety.

What is Lion’s Mane Mushroom?  

Hericium Erinaceus or Lion’s Mane is an edible medicinal mushroom which has been used in traditional chinese medicine for thousands of years. It is believed to treat cancer, gastric ulcers, and improve brain health [2]. Native to North America, Asia, and some parts of Europe, this fungus can grow on living or dead hardwood [3]. Its fruiting body gives the mushroom a unique ball-like structure covered in hanging spines that resemble the mane of a lion [3]. The mycelium, also called vegetative body, lies underneath. Both fruiting body and mycelium contain beneficial bioactive compounds, whose potential benefits for treating a variety of diseases are increasingly being explored [4]. 

What Does the Data Say?

Traditional chinese medicine considers Lion's Mane mushroom to be a powerful remedy that can improve brain health as well as several other health conditions, but what does the research show? As it turns out, a growing body of evidence supports the notion that Lion's Mane extract may possess neuroprotective properties. 

Studies in Animal Have Found: 

  • Enhanced recovery from nerve injury from daily supplementation of Lion’s Mane extract in rats [5]
  • Reduced oxidative stress and inflammation in mice [6], both of which play a role in cognitive health and Alzheimer’s disease. You can read our earlier blog post Inflammatory Alzheimer’s to learn about how inflammation contributes to the development of disease. 
  • Reduced anxiety in mice bred to have Tau tangles  [7,14] 
  • Enhanced memory (locomotor, short-term, spatial) in mice [8]

Studies in Humans Have Found: 

  • Improved cognitive performance after 16 weeks with daily supplementation of dried Lion’s Mane powder [9]. These findings were reported in a Japanese study conducted mend and women with mild cognitive impairment.
  • Improved short-term memory after 12 weeks of daily supplementation with fruiting body [10]
  • Improved Cognition and Activities of Daily Living scores in subjects diagnosed with mild Alzheimer’s Disease after 49 weeks of daily supplementation with Lion’s Mane mycelium extract [11]. This is the first study to directly test the effects of lion’s mane supplementation on patients with some for of Alzheimer’s.

How Might Lion’s Mane Actually Work to Improve Brain Function?

Lion's Mane extract may improve cognition through a number of mechanisms, some of which will be discussed in this article. It is likely that these apparent cognitive benefits are due to the fact that numerous bioactive compounds from the mycelium and fruiting bodies have the ability to cross the blood-brain barrier [12]. This could have profound implications in the treatment of Alzheimer's disease. Lion’s mane extract may:

  • Promote nerve growth factor (NGF) and Brain Derived Neurotrophic Factor (BDNF) biosynthesis: these compounds are important for neuroprotection and nerve regeneration  [12, 13, 15] 
  • Act as an antioxidant: can scavenge free radicals, prevent LDL oxidation, and reduce oxidative stress [16, 17]
  • Reduce Tau Tangles [7]. This was foind in mice.
  • Improve AB plaque burden [18, 19] in mice. 

It should be noted that most of the existing research is either in vitro, which means it was conducted in a controlled environment (e.g. petri dish) outside a living organism, or in animals. These data are generally not translatable to humans, and more human studies are needed.

Choosing a Lion’s Mane Supplement

Several companies currently produce and sell lion's mane extract. It is generally available for purchase in capsule form, as a tincture, or as a powder. 

If you are interested in supplementing with lion’s mane, you may want to consider the following:

  • Is the company third-party tested? In the US, supplements are not regulaated by the FDA, so the best way to ensure quality is through third-party testing. 
  • Does the company have positive reviews? If you are unsure, checking reviews from other customers is another way to help verify product efficacy. Do not check reviews on a company’s own website, as these can easily be forged.
  • Is it produced in the United States? Products made outside the US are more difficult to regulate and may contain toxic ingredients. Check to see if you can find a company that manufactures lion’s mane near you. This would also reduce emissions from transportation if you want to keep sustainability in mind. 

So What Does This Mean For Alzheimer’s?

There are a number of ways in which lion’s mane extract may improve cognitive function and protect brain health. Among the benefits for Alzheimer's disease are: 

  • Improved tau tangles and beta amyloid plaque, the hallmarks of Alzheimer’s disease.
  • Reduced inflammation and oxidative stress, both of which contribute to disease progression and pathology
  • Increased production of BDNF and NGF, which are key factors in neuroregeneration and neuroprotection. 

To date, only single study has directly investigated the effects of lion’s mane supplementation on patients diagnosed with Alzheimer’s (early-onset Alzheimer's, in this case) [11], indicating a need for further research in this area to confirm these effects in humans.  

Uses, Safety & Side Effects

If you are interested in supplementing with Lion’s mane, here are a few ways you can integrate it into your life and diet:

  • Take a supplement: this is probably the simplest method. Refer to the previous paragraph on choosing the right supplement.
  • Use as a tea: you can do this with a powder or a tincture. Add some to your morning coffee or tea, to hot water, or even a smoothie.
  • Cook it: You can buy whole fresh lion’s mane and cook a delicious “steak” with it. Several recipes are available and easy to find through a quick Google Search. 

Data from animal and human studies suggest that lion’s mane extract is safe for consumption and well-tolerated as a supplement [11, 20]. That being said, if you have a history of autoimmune disorders or previous allergic reactions to mushrooms, consult your doctor or healthcare provider before trying any supplement.

Conclusions

There is promising therapeutic potential in Lion's Mane mushroom for treating cognitive deficits. Amazingly, research is showing it may prevent or treat Alzheimer’s by acting directly on Tau tangles and beta-amyloid plaque, reducing oxidative stress and inflammation, stimulating the growth of new neurons and more. However, the fact remains that relatively few clinical trials have investigated these benefits in humans and therefore more research is needed to confirm these results. If you are concerned that you may be suffering from mild cognitive impairment or have been diagnosed with Alzheimer’s disease and wish to supplement with Lion’s Mane, speaking to a licensed health professional is so important. Contact the Amos Institute today to schedule a consultation with a dietitian trained in the Bredesen Protocol and functional medicine.

--- References:

  1. Gora, 2022: https://www.livescience.com/what-are-medicinal-mushrooms
  2. Friedman, 2015: https://pubs.acs.org/doi/10.1021/acs.jafc.5b02914
  3. Rossi et al., 2018: https://pubmed.ncbi.nlm.nih.gov/29953363/
  4. Ma et al., 2010: https://www.tandfonline.com/doi/full/10.1080/21501201003735556
  5. Wong et al., 2015: https://www.scielo.br/j/cta/a/7Lqm37PzpCjxKn6VcQ5WbrF/?lang=en
  6. Trovato et al., 2018: https://pubmed.ncbi.nlm.nih.gov/29456585/
  7. Rodriguez & Lippi 2022: https://pubmed.ncbi.nlm.nih.gov/35877305/
  8. Marmol et al., 2020: https://www.biorxiv.org/content/10.1101/2020.08.28.271676v1
  9. Mori et al., 2009: https://pubmed.ncbi.nlm.nih.gov/18844328/ 
  10. Saitsu et al., 2019: https://doi.org/10.2220/biomedres.40.125
  11. Li et al., 2020: https://doi.org/10.3389%2Ffnagi.2020.00155 
  12. Ma et al., 2009: https://doi.org/10.1080/21501201003735556
  13. Ryu et al., 2021: https://doi.org/10.1016/j.bmcl.2020.127714
  14. Li et al., 2020: https://doi.org/10.1186/s12906-021-03463-3
  15. Samberkar et al., 2015: https://doi.org/10.1615/intjmedmushrooms.v17.i11.40
  16. Ghosh et al., 2021: https://doi.org/10.1615/intjmedmushrooms.2021040368
  17. Rahman et al., 2014: https://doi.org/10.1155/2014/828149
  18. Tsai-Teng et al., 2016: https://doi.org/10.1186/s12929-016-0266-z
  19. Liu et al., 2015: https://doi.org/10.1615/intjmedmushrooms.v17.i3.20
  20. Lee et al., 2019: https://doi.org/10.1615/intjmedmushrooms.2019030320
  21. Sims et al., 2022: https://doi.org/10.1155%2F2022%2F3889300