Benefits and Side Effects of Reishi Mushrooms

Reishi mushrooms are an increasingly popular for their potential health benefits, including boosting the immune system.
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Mushrooms are having their moment. Taking supplements, eating foods that include reishi mushroom extract or drinking coffee with mushroom powder may have positive effects on your health. Reishi mushrooms may have the potential to improve health conditions as well as benefit immune function.


Reishi mushrooms are an increasingly popular for their potential health benefits, including boosting the immune system. Be mindful and consult with your doctor prior to taking any reishi mushroom supplements or extracts.

The Benefits of Reishi Mushrooms

The reishi mushroom may enhance immune response and contains anti-oxidant properties, according to Memorial Sloan Kettering Cancer. Because reishi mushrooms contain complex sugars known as beta-glucans, it is suggested that these compounds may strengthen immune response and even potentially help stop the growth and spread of cancer cells.


Because these types of anti-oxidants defend against free radicals with anti-inflammatory properties, mushroom powder is said to have health benefits such as fighting the common cold and even lowering the risk or aiding in more serious conditions such as cancer.

Read more: All About the Reishi Mushroom Coffee Craze

The Right Reishi Mushroom Dosage

Edible mushrooms have significant medicinal properties, according to a September 2017 study published in the International Journal of Molecular Sciences. These types of mushrooms can account for better prebiotics to stimulate the gut microbiota. Prebiotics help support helpful bacteria and other organisms in the gut, leading to increased gut health. Mushrooms are advantageous in that they're more readily available as when compared to other prebiotics such as seaweed.


The correct reishi mushroom dosage depends on what type you are utilizing, as consuming the mushroom itself tends to provide a higher dose while consumption of extracts or dried mushroom powder offers a lower dosage. According to Memorial Sloan Kettering Cancer Care, take 1 gram or up to 1.5 grams of reishi mushroom powder daily to boost your immunity.

The study explained that mushrooms contain various active polysaccharides and can act as immune-boosting agents to activate healthy gut microbiota. These types of mushrooms may play a significant role in regulating gut microbiota which can improve gut health.


Certain types of mushrooms have nutritional benefits that can improve health while also aiding in healthy digestion. Reishi and other medicinal mushrooms may have stress fighting adaptogens, which are non-toxic herbs and roots that can help the body handle stress and maintain a balanced state. These adaptogenic herbs can be found in over-the-counter herbal supplements such as the brand Pukka herbs teas and supplements.

Read more: What Exactly is Chaga Mushroom and Can it Help You Lose Weight?

Other Effects of Reishi Mushrooms

Published in the International Journal of Mushrooms, a 2013 study concluded that the reishi mushroom helped improve liver health in mice. The results demonstrated that mushrooms aided in the effects on acute liver injury. An April 2015 study published in Cochrane Database System Review examined the use of reishi and other mushrooms as an alternative medicine and complementary therapy for cancer patients to manage the symptoms and cope with the side effects of radiation and chemotherapy.


The study suggested promising results of these extracts as an immune system support supplement in cancer treatment that potentially had anti-tumor effects. This, however, was only recommended as an effect when combined alongside with traditional cancer care treatments such as radiation and chemotherapy.

Side Effects of Reishi Mushrooms

According to Memorial Sloan Kettering Cancer Care, reishi mushrooms side effects may include nausea and insomnia in some cancer patients. In rare cases, liver toxicity was a reported side effect. Chronic diarrhea in a man with non-Hodgkin's lymphoma following long-term use of a powdered reishi mushroom extract also occurred.

For the general consumer, consuming too much reishi mushroom may cause adverse effects such as upset stomach, skin rashes or nausea.


Do not take reishi if you are currently taking blood thinners including warfarin, as it may increase bleeding. Those undergoing chemotherapy or taking immunosuppressants should also avoid taking reishi, as it can make chemotherapy drugs less effective and stimulate immune response. If you are taking cytochrome P450 2E1, 1A2, and 3A substrate drugs, do not take reishi as lab studies suggest compounds in reishi may affect drug concentrations.

Women who are pregnant should consult their physician prior to using any reishi mushroom supplements. Those with conditions such as low blood pressure should avoid taking herbal supplements such as reishi mushrooms unless directed by their physician.