Mushrooms have been used for centuries in traditional Asian medicine. Recently, scientists have begun to systematically study the unique substances mushrooms contain and their medicinal effects. Early results raise hopes that these ancient medicines really may have potent cancer-fighting potential.
In 2004, for instance, Japanese scientists reported that an extract from cordyceps mushrooms, a medicinal mushroom widely used in traditional Chinese medicine, reduced the size of experimental skin cancer tumors in mice by 36 percent. A 2008 study conducted by researchers at the Beckham Research Institute in Duarte, Calif., showed that an extract of white button mushrooms can slow the growth of prostate cancer cells in mice. But the leap from successfully treating animals to treating humans is huge.
How mushroom extracts work against cancer cells isn’t well understood. Preliminary findings suggest that substances they contain may inhibit the growth of cancer cells and may also trigger a mechanism that causes malignant cells to self-destruct. There’s also evidence that substances in certain mushrooms may boost the immune system’s ability to detect and destroy cancer cells.
“We certainly don’t recommend mushroom extracts as an alternative to conventional chemotherapy or other treatments for cancer,” says Donald Abrams, M.D., who practices oncology the Osher Center for Integrative Medicine at the University of California, San Francisco, and is actively studying medicinal mushrooms. “But we’re very excited about the prospect of using some of these extracts along with chemotherapy or radiation to boost their effectiveness.”
Abrams feels comfortable encouraging patients who show an interest to try medicinal mushrooms, as long as they are in a doctor’s care. “We know from many centuries of use that these traditional treatments pose very little risk of harm,” he points out.
But results from one recent human experiment urge caution.
When researchers at Memorial Sloan Kettering Cancer Center in New York followed 34 breast cancer patients who were taking medicinal mushroom extracts, they found that while some immune functions were boosted, others were suppressed. “I think we have to be very careful about anything that people are taking by mouth until we know both their beneficial effects and any harmful side effects,” says Barrie Cassileth, M.D., chief of integrative medicine at Memorial Sloan-Kettering Cancer Center.
Experts agree on a few things. If you’re interested in trying medicinal mushrooms, talk to your doctor first. If your doctor isn’t able to advise you, seek out an expert in the field of integrative medicine, preferably someone affiliated with a university medical center. Tell your primary cancer doctor about anything and everything you take, especially pills or potions taken by mouth.
Peter Jaret is a freelance writer in Petaluma, Calif.