Cancer: Could consuming mushrooms reduce the risk?
Written by Lori Uildriks on May 4, 2021 — Fact checked by Rita Ponce, Ph.D.
Share on PinterestIs there a link between mushroom consumption and cancer risk? Laszlo Nagy/EyeEm/Getty Images
- A recent meta-analysis of 17 observational studies found an association between an increased consumption of mushrooms and a lower risk of cancer.
- In participants who eat 18 grams (g) of mushrooms daily, the meta-analysis found a 45% decrease in the relative risk of cancer, compared with participants who eat no mushrooms.
- Further research is needed to delineate the protective effects of mushrooms and their potential role in the dietary prevention of cancer.
Cancer is the second-leading cause of death in the United States, with approximately 608,570 people projected to die from the disease in 2021.
Potentially preventable risk factors such as smoking, excess body weight, poor nutrition, and excess sun exposure are associated with many cancers.
Free radicals, which form in the body during many cellular processes, are extremely reactive substances that, in high concentrations, can potentially harm cells. Damage to DNA caused by free radicals may contribute to the development of cancer.
Dietary factors account for about 4% of all cancer cases. Diets incorporating fruits, vegetables, whole grains, fish, poultry, and fewer processed and red meats are associated with lower cancer risk. Fruits, whole grains, and vegetables are sources of antioxidants.
Antioxidants neutralize free radicals in the body, thereby preventing damage. Although the body produces some antioxidants internally, it primarily relies on those taken in through the diet.
Rich dietary antioxidant source
Mushrooms are rich in fiber, vitamins, minerals, and antioxidants. They are excellent dietary sources of two antioxidants: ergothioneine and glutathione.
In particular, ergothioneine may have a protective role against cancer. Ergothioneine concentrations differ by mushroom type, with oyster, shiitake, maitake, and king oyster mushrooms having higher concentrations than cremini, portobello, or white button mushrooms.
Previous laboratory studies have demonstrated that mushrooms have anticancer effects. However, prior observational studies provided mixed results, with some demonstrating decreased cancer risk with increased mushroom intake, while others found non-significant correlations.
A previous meta-analysis that investigated the association between cancer risk and mushroom consumption was limited — it included only seven studies and examined breast cancer risk alone. This prompted researchers at the Penn State College of Medicine and Pennsylvania State University to conduct a more comprehensive systematic review and meta-analysis of observational studies.
The researchers have published their findings in the journal Nutrition.
The new meta-analysis included 17 observational studies published between January 1, 1966, and October 31, 2020, with 11 case-control study designs and six cohort study designs. The outcomes examined included total cancer and site-specific cancer risks.