Nutrition Information

Prostate cancer is becoming an increasingly important public health problem in the United States. The early detection of prostate cancer has improved in recent years due to the development of the prostate-specific antigen (PSA) test and increased awareness of the disease. In the U.S., prostate cancer is now the most commonly diagnosed cancer in men as well as the second leading cause of male cancer deaths. It is estimated that there will be 180,400 newly diagnosed prostate cancer cases and 31,900 men will die of the disease in 2001.

Despite efforts to study its causes, little is as yet known regarding what initiates the disease. Without knowledge of exact cause of prostate cancer, we do not know if it is possible to prevent most cases of the disease. Many risk factors, such as a man's age, race, and family history, are beyond his control, but other risk factors may be controllable. One possible risk factor that can be changed is diet. The diet consumed in Western industrialized nations may be one of the most important environmental factors that affect the development of prostate cancer.

Many efforts have been devoted to studying associations between nutrition and prostate cancer.

One of the most consistent associations with prostate cancer risk has been with dietary fat intake. Studies of per capita total fat consumption among nations of the world show a strong correlation between mortality rates from prostate cancer and fat consumption. Intakes of animal fat generally are positively associated with prostate cancer, while vegetable fat consumption has shown no effect. Beyond this, the families of essential fatty acids have been studied for their association with prostate cancer risk. Alaskan Natives have a very low prostate cancer rate that has been attributed to their high intakes of fatty fish rich in omega-3 fatty acids. Studies in Japan and Minnesota have also shown a significant protective effect of fish consumption on 60% and 30% lowered chance, respectively, for developing prostate cancer.

Additionally, prostate cancer has been found to be 54% more likely among non-vegetarians in the Seventh Day Adventist’s Study than among vegetarians with similar lifestyles. Although this may reflect a multitude of dietary differences, well-cooked meats are a source of heterocyclic amines, which are produced in high temperature cooking. Although the carcinogenic potential of heterocyclic amines in laboratory animals is well established, carcinogenic potential in humans is not.

Some fruits and vegetables, such as cooked or raw tomatoes, grapefruit, and watermelon, have high levels of lycopenes (vitamin-like substances). Many vegetables also contain the mineral selenium. Both are antioxidants that can help prevent damage to DNA and may help lower prostate cancer risk.

Prostate cancer is lower in countries that subsist on diets rich in grains and legumes and low in meats. Epidemiological studies have identified legumes as possible protective agents in the decreased risk of breast, colon, and prostate cancers in vegetarian populations. Since these seeds contain high concentrations of protease inhibitors, agents closely associated with PSA in blood, they may limit the occurrence of these cancers in humans.

The role of vitamin supplements in reducing prostate cancer risk is not entirely certain, but some studies suggest that taking 50 milligrams of vitamin E daily can lower risk by 32%. Although other studies found vitamin E to be of no benefit, reasonable doses of this vitamin have no significant side effects and are not expensive. On the other hand, some studies suggest that taking vitamin A supplements may actually increase prostate cancer risk. As always, vitamin supplements should be used with caution, avoiding excessive doses.

In summary, a diet low in fat and consisting mostly of vegetables, fruits, and grains is associated with reduced risk of prostate cancer. As the American Cancer Society recommends, you should limit your intake of high-fat foods from animal sources and choose most of the foods you eat from plant sources. Eat five or more servings of fruits and vegetables each day. Bread, cereals, grain products, rice, pasta, and beans are also recommended to reduce the chance of developing prostate cancer.