Treatment for prostate cancer is continually improving but, currently, there is neither a cure nor a way to prevent it. However, researchers have recently discovered that eating mushrooms may help reduce the risk of such cancers. The beneficial effect is relatively minor, but the findings are likely to inspire further investigation.
The study was led by researchers at the University School of Public Health (Japan) and has been published in the International Journal of Cancer. For the study, a total of 36,499 men between the ages of 40 and 79 were surveyed and asked to complete a questionnaire about lifestyle choices, such as diet (including mushroom consumption), physical activity, smoking and drinking habits. Participants were also asked to provide information on their education, family and medical history.
Each participant was then categorised into one of five groups, based on their level of mushroom consumption: almost never (6.9%), 1-2 times a month (36.8%), 1-2 times a week (36%), 3-4 times a week (15.7%) and almost every day (4.6%). During the follow-up period, researchers discovered 1,204 cases of prostate cancer among the participants, a total of 3.3%.
Analysis of the data, after controlling for variables, revealed a significant beneficial effect of mushroom consumption. Compared with those who ate mushrooms less than once a week, those who ate mushrooms 1-2 times each week had an 8% lower relative risk of prostate cancer. Those who ate mushrooms 3-4 times each week had a 17% lower relative risk. Eating mushrooms also appeared to be particularly beneficial among men aged 50 and older, among those who consumed a large amount of meat and dairy products and little fruit and vegetables.
“Test-tube studies and studies conducted on living organisms have shown that mushrooms have the potential to prevent prostate cancer. However, the relationship between mushroom consumption and incidence of prostate cancer in humans has never been investigated before. To the best of our knowledge, this is the first cohort study indicating the prostate cancer-preventive potential of mushrooms at a population level,” said lead researcher Dr Zhang Shu.
Mushrooms are a relatively inexpensive and a widely consumed food throughout the world. In recent years, studies have begun to identify their potential disease fighting capabilities. According to the study, mushrooms are a good source of vitamins, minerals and antioxidants which are believed to mitigate oxidative stress. This type of stress comes through a cellular imbalance caused by poor diet and lifestyle choices. Mushrooms have also been known to mitigate exposure to environmental toxins which lead to chronic inflammation and, eventually, to chronic diseases such as cancer.
However, there are certain limitations to the study. Firstly, using self-reported dietary information is not ideal because it is open to error and misreporting. But for a study of this size, there is no viable alternative. As the study is purely observational, the authors cannot definitively conclude that mushrooms caused the reduction in cancer risk. Although this research was not designed to uncover how mushrooms might protect against cancer, the authors believe that this effect might be due to their antioxidants.
“The results of our study suggest mushrooms may have a positive health effect on humans,” said Dr Zhang. “Based on these findings, further studies that provide more information on dietary intake of mushrooms in other populations and settings are required to confirm this relationship.”