There is no way to prevent prostate cancer because there is no known cause. However, there are certain risk factors that can increase a man’s chance of developing prostate cancer. Studies have shown that dietary changes may lower the risk of the disease. Eating less meat, particularly red meat, and fat may reduce the risk. In addition, adding five servings or more of fruits and vegetables every day can reduce the risk of this cancer, as well as other diseases. 

Other studies showed that medications used to reduce cholesterol levels may decrease the risk of having advanced prostate cancer. Although not part of the study, cholesterol helps create the hormone testosterone, which may affect the growth of the cancer.

Researchers have investigated the effect of certain vitamins and supplements on prostate cancer. Some studies have indicated that a daily dose of vitamin E may lower the risk of prostate cancer. However, other studies have found it to have no impact. A large study is currently under way to evaluate the use of vitamin E and selenium to prevent prostate cancer.

Another study examined the use of the drug finasteride in lowering the risk of prostate cancer.  The study found that men taking the drug had a 25 percent lower risk of getting prostate cancer. However, those who developed the disease appeared to have cancers that were more prone to spreading. They also developed a number of side effects, including a lower sex drive and erectile dysfunction. Additional research is necessary to determine if finasteride can lower the risk of prostate cancer.