A few studies suggest that oyster mushrooms (Pleurotus ostreatus) may have anticancer properties. However, this does not prove that they can treat cancer in the human body, nor that they are a replacement for standard cancer therapies.

Oyster mushrooms have long played a role in traditional and folk medicine. More recently, practitioners of alternative and complementary medicine have lauded the benefits of mushrooms, with many people reporting anecdotal benefits online.

Scientific research studying the benefits of mushrooms is relatively new. Researchers also have not thoroughly investigated the anticancer properties of mushrooms generally or oyster mushrooms specifically. A 2021 study found that higher consumption of mushrooms correlates with a lower risk of cancer.

There is no evidence that adding mushrooms to a person’s diet, including to fight cancer, is harmful. However, mushrooms are not a viable substitute for medical cancer treatments, and the studies on their use have not proven any specific benefits in humans.

Read on to learn more about oyster mushrooms for cancer.

Close up image of oyster mushroomsShare on Pinterest
Tatjana Zlatkovic/Stocksy

While blogs, message boards, and natural health sites claim that the benefits of oyster mushrooms for cancer are immense, there is almost no quality scientific research to support this claim.

It is important to consider that this does not disprove the benefits of oyster mushrooms. Rather, it means that scientists have not thoroughly tested them. More data might offer compelling research in favor of oyster mushrooms, find that there is no benefit at all, or even find that they are harmful.

One of the most significant sources of the claim that mushrooms help cancer is from a 2021 systematic review and meta-analysis. This review included 17 studies and more than 19,500 people.

Researchers found that having more mushrooms in the diet correlated with a lower risk of certain types of cancer, especially breast cancer.

The review’s authors suggest that mushrooms may have antioxidant properties thanks to components such as ergothioneine and glutathione. Antioxidants may help reduce the effects of oxidative damage and age-related decline, potentially lowering the risk of cancer.

But this does not mean mushrooms can treat cancer once it already exists.

A small number of studies on animals and studies of human cancer in a laboratory setting suggest that some mushrooms, including oyster mushrooms, may have anticancer benefits. A 2020 review emphasizes their benefit against breast cancer.

Another 2021 review highlights specific chemicals in oyster mushrooms that may offer anticancer benefits. The review’s authors emphasize the antiproliferative benefits of certain polysaccharides in oyster mushrooms. However, the paper does not directly test the benefits of these chemicals in the human body.

The research on other benefits is also scant but not nonexistent.

Some data suggest that oyster mushrooms may offer benefits to people with autoimmune diseases.

A 2015 paper reports that mushrooms may be an effective immunotherapy for people who are immunocompromised.

Additionally, a 2020 paper reports that oyster mushrooms may help with several measures of heart health, including:

  • improving lipid metabolism
  • reducing or controlling appetite
  • managing blood pressure
  • managing weight

Read more about the nutritional value of mushrooms.

The main risk of using mushrooms as a cancer treatment is that a person might avoid standard, proven treatments.

There is no specific research demonstrating any widespread or common risks relating to oyster mushrooms. But as with any food, it is possible for a person to develop allergies or sensitivities.

Researchers have not found any specific side effects most people experience with oyster mushrooms. Anecdotally, some individuals reported gastrointestinal issues such as diarrhea or vomiting.

Since researchers have not thoroughly studied mushrooms, it is possible that they could negatively interact with medications. This may include reducing the effectiveness of cancer medications or causing harmful side effects.

Many different treatments exist for cancer. In some cases, it may be possible to cure the disease with the right treatment.

All of these treatments have significant research supporting them, in contrast to the very limited research exploring oyster mushrooms for cancer. These treatments include:

  • surgery to remove cancer
  • chemotherapy and radiation to kill cancer cells
  • immunotherapy to help the immune system fight cancer
  • targeted cancer treatments
  • hormonal therapies
  • treatments to manage cancer symptoms

The right treatment depends on the type of cancer a person has, their overall health, and treatment goals.

Some people consider oyster mushrooms an alternative therapy for cancer. However, research does not support the idea that they can replace standard medical therapies.

Mushrooms have also been an important part of folk and traditional medicine for generations. More research might uncover additional benefits or none at all.

People considering complementary treatments, including mushrooms, should talk with a doctor first. In some cases, mushrooms may be perfectly safe, but they could also harmfully interact with other treatments and medications.