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If you want to jump on the mushrooms-as-medicine trend, you may consider talking with your doctor or an integrative registered dietitian about lion's mane. This shaggy large white fungus has long been part of medicinal culture in eastern Asia. “Lion's mane has been used for centuries for its many medicinal purposes,” says Trista Best, RD, of the Candida Diet.
Although there is an increase in interest in lion's mane for a variety of health conditions, more information is needed. Research in humans is limited, and many of the studies are small.
Lion's mane mushrooms may offer benefits for cognitive function, digestion, mood, and other health concerns. However, much of the research has been done with animal subjects, and studies in humans have been small, with fewer than 100 participants. More robust studies are needed, and in the meantime, interpret the current research with caution.
Still, more concrete evidence is needed to determine if lion's mane can truly boost your brain function. “Some studies suggest that lion's mane may modestly improve cognitive function in people with mild cognitive impairment, but it does not appear to help those with Alzheimer's disease or healthy adults of any age,” says Michael Ednie, MD, RD, medical director of Bespoke Concierge MD, who is based in Fort Lauderdale, Florida. “Overall, current evidence does not strongly support lion's mane for cognitive enhancement, especially in healthy individuals.”
Properties of lion's mane have been shown to support the digestive tract. “In particular, lion's mane may help prevent ulcers by inhibiting the growth of a bacteria — Helicobacter pylori — that can have negative effects on your gut lining,” says Monique Richard, RDN, of Johnson City, Tennessee.
“Lion's mane mushrooms show promise for gut health based on laboratory and animal studies,” says Dr. Ednie. “But no studies have directly tested lion's mane by itself for gut health in humans, so more research is needed to confirm its effects.”
Lindsay Delk, RDN, who is based in Hearne, Texas, and specializes in the connection between food and mental health, says that lion's mane decreases inflammation, which may help manage depression and anxiety.
“Lion's mane [may] help with stress by managing cortisol levels,” says Best. “Cortisol is known as the stress hormone; it is produced by the adrenal glands in response to stress. When this hormone is elevated for a long period of time, it can result in anxiety and other mood issues.”
However, one limitation of this study is that it included only 30 women. Larger studies are needed to show how these findings might help with anxiety and to see how lion's mane compares or combines with mainstream therapies for anxiety like meditation and talk therapy.
“There is interest in lion's mane for depression due to its ability to stimulate nerve growth factor,” says Ednie. “However, clinical evidence is weak.”
Research in animals suggests that lion's mane may strengthen the immune system, helping protect against bacteria, viruses, and other harmful substances.
“Lion's mane mushrooms appear to support and modulate immune function, primarily by enhancing gut health, reducing inflammation, and activating key immune cells, though most evidence to date comes from animal and laboratory studies rather than large-scale human trials,” says Ednie.
Since most of the research on lion's mane has been done in animals, more research is needed in humans to determine how it might benefit the immune system in humans.
Lion's mane has several unique compounds that may help fight cancer in mice and lab studies, though researchers aren't sure how this translates to humans.
“Lion's mane mushrooms have shown anticancer effects in laboratory and animal studies, but more research is needed to determine the safety and effectiveness in people,” says Ednie.
“Lion's mane mushrooms may help lower blood sugar, improve insulin levels, and reduce diabetic complications such as nerve pain — these effects have been seen mainly in animal studies,” says Ednie.
However, people with diabetes who are taking medication to control their blood sugar should approach lion's mane with caution. Lion's mane may interact with other diabetes treatments, causing blood sugar levels to dip, Richard says.
In addition, most of the research in diabetes has been done in animals and test tubes — more studies in humans may show if lion's mane can help with diabetes.
“Lion's mane mushrooms may help reduce heart disease risk by lowering cholesterol and triglycerides, preventing cholesterol oxidation and possibly reducing blood clot risk, but these effects have been shown mainly in animal and lab studies,” says Ednie. “There is not enough evidence from human trials yet to confirm these benefits.”
Despite these findings, Michelle Routhenstein, RDN, a preventive cardiology dietitian and certified diabetes care and education specialist at Entirely Nourished in New York City, doesn't recommend using lion's mane to prevent or treat heart disease. “It's not supported by human studies, and the safety and side effects haven't been studied either,” she says, adding that there are safer, more effective ways to prevent heart disease through your diet, under the care of your primary physician.
Lion's mane has a few potential risks and side effects. Whether you want to try these mushrooms in a recipe or are considering them in supplement form, talk to your healthcare provider first.
Potential risks of lion's mane include bleeding and slower blood clotting.
“There is a very low risk of increased bleeding, as lion's mane mildly inhibits platelet aggregation, but this effect is weaker than aspirin and not likely clinically significant,” says Ednie. If you have a history of statin-induced autoimmune muscle disease, it's also best to avoid lion's mane, due to possible statinlike compounds, adds Ednie.
Overall, lion's mane is considered to be well tolerated by healthy people. “Lion's mane supplements are generally considered safe for most people when used for up to a year in clinical studies, with mild side effects such as abdominal discomfort and nausea being the most commonly reported,” says Ednie.
Of course, people with mushroom allergies should avoid lion's mane. “Rarely, allergic reactions can occur, including skin rash and breathing difficulties, especially in individuals allergic to other mushrooms,” says Ednie.
Here are Richard's tips for choosing and using lion's mane:
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Grant Chu, MD, is an associate clinical professor at the David Geffen School of Medicine at UCLA. Dr. Chu is also associate director of inpatient East-West consult services at the …
Kelsey Kloss is a health and wellness journalist with over a decade of experience. She started her career as an in-house editor for brands including Reader’s Digest, Elle Decor, Go…