Does eating mushrooms really cut your cancer risk in half?

When nutritional consultant Lori Shemek tweeted last week that “cancer absolutely hates mushrooms,” she dug up the age-old morel dilemma — can eating mushrooms really help reduce the risk of cancer?

Shemek referenced a 2021 Penn State University study that found that people who ate 18 grams of any kind of mushroom — about 1/8 to 1/4 cup — a day had a 45% lower risk of cancer compared to those who did not eat any mushrooms. Researchers credited the abundance of ergothioneine, a potent antioxidant that protects cells.

Other research has found a link between eating mushrooms and a lower risk of prostate cancer and breast cancer.

The University of Texas MD Anderson Cancer Center notes that mushroom extracts have routinely complemented cancer care in Japan and China because they are rich in vitamin D, which is critical for the immune system.

But you may struggle to find medicinal mushrooms at a grocery store. Ganoderma lucidum (reishi), Trametes versicolor or Coriolus versicolor (turkey tail), Lentinus edodes (shiitake) and Grifola frondosa (maitake) are the mushrooms most commonly used to treat cancer in Asia, according to the National Cancer Institute.

Shiitake mushrooms can be purchased whole in grocery stores, while the others are sold as supplements online or in health food stores.

The Food and Drug Administration has not approved the use of medicinal mushrooms to treat cancer.

Heather Hallen-Adams, an assistant professor of food science and technology at the University of Nebraska-Lincoln, explained to National Geographic in January that while compounds in shiitake, turkey tail and other mushrooms have shown promise in the fight against tumors, research has mostly been limited to rodents and cells grown in labs.

“The vast majority of studies are not double-blind, placebo-controlled clinical studies” — the standard in drug-approval processes, David Hibbett, a professor of biology at Clark University, told the outlet.

“It’s a really dicey literature,” he added. “Until you get to clinical studies with actual people, you’re not in a position to say that a product has actual health benefits.”

The American Institute for Cancer Research points out that no one food can protect against cancer, but experts say that a diet rich in vegetables, fruits, whole grains, beans and other plant foods can lower the cancer risk.