Study Suggests Link Between Eating Mushrooms and Decreased Risk of Prostate Cancer

A scientific study that lasted almost 25 years has found evidence suggesting that the regular consumption of mushrooms may be related to lower chances of developing prostate cancer.

The findings of the study, published September 5 in the International Journal of Cancer, was conducted by researchers at Japan's Tohoku University Graduate School of Medicine.

According to a press release about the study, prostate cancer is a disease that begins when the cells in the prostate—a walnut-shaped gland found only in males that helps produce semen—start to grow out of control. The likelihood of developing the disease increases with age.

It is one of the most common cancers in males, the press release read, with over a million new cases diagnosed in 2018 alone. The disease kills an American male about every 17 minutes, which approximates 86 deaths per day and 31,620 within a year, according to a nonprofit called ZERO—The End of Prostate Cancer.

For the study, researchers monitored 36,499 men between the ages of 40 and 79. They were divided into two groups—the first consisted of men living in Miyagi Prefecture who were monitored beginning in 1990, and the second lived in Ōsaki and were monitored from 1994.

Each of the men was asked to complete a questionnaire that asked to provide information about his lifestyle choices, including his diet, physical activity, smoking and drinking habits, as well as his medical and family history.

"Long-term follow-up of the participants indicated that consuming mushrooms on a regular basis reduces the risk of prostate cancer in men," the press release read, "and was especially significant in men aged 50 and older and in men whose diet consisted largely of meat and dairy products, with limited consumption of fruit and vegetables."

Those participants who reported eating mushrooms three or more times a week had a 17 percent lower chance of developing prostate cancer compared to those who said they ate mushrooms less than once a week. Those who ate less mushrooms—once or twice a week—were still 8 percent less likely to develop the disease than men who ate mushrooms less frequently than once a week.

The study is of note because it is the first to examine the precise relationship between eating mushrooms and the development of prostate cancer in humans as opposed to only within a laboratory.

"Test-tube studies and studies conducted on living organisms have shown that mushrooms have the potential to prevent prostate cancer," Shu Zhang, an assistant professor of epidemiology at Tohoku University and lead author of the study, said. "However, the relationship between mushroom consumption and incident prostate cancer in humans has never been investigated before."

Previous studies have suggested that eating a diet high in vegetables and legumes such as cauliflower, broccoli and beans as well as fish may also be linked to a lower likelihood of developing prostate cancer, according to the American Cancer Society, which also stated that a regular exercise regimen has been demonstrated to lower a person's chances of developing the disease.

Mushrooms may have this positive effect on men's health partly because they are rich in an amino acid called L-ergothioneine, Zhang said. This is believed to be useful to the body for combating oxidative stress, a cellular imbalance that results from a poor diet and unhealthy lifestyle as well as exposure to environmental toxins. It can lead to chronic inflammation that can ultimately result in cancer.

Zhang suggested that the findings of the study might be of use to American men in particular.

"Considering the average American consumes less than five grams of mushrooms per day, which is lower than that consumed by the participants in this study (7.6 g/day) one would expect that even a small increase in mushroom consumption to offer potential health benefits," he said.