Researchers still do not know what causes prostate cancer. They have, however, been able to identify risk factors that consistently associated with prostate cancer. The role that some identified risk factors play in the development of prostate cancer is less clear because research studies have provided conflicting results in some areas.

Visit HealthAtoZ for moreinformation. Age: After age 50, the chance of developing prostate cancer begins to increase. More than 80 percent of all prostate cancers occur in men 65 years and older.

Race: Prostate cancer is twice as prevalent among African-American males as it is among their Caucasian counterparts.

Ethnicity: Prostate cancer is most common in North America and northwestern Europe. It occurs less frequently in Asia, Africa, Central America and South America.

Diet: The results of most studies show men who eat a high-fat diet have an increased chance of developing prostate cancer. Some research has shown that men who eat higher-fat diets tend to eat less fruits and vegetables and more low-fat dairy products. These factors may also play a part in the development of prostate cancer.

Recent studies show a diet high in lycopenes (found in higher levels in colorful fruits and vegetables) and selenium, may lower the risk of developing prostate cancer.

Exercise: Maintaining a healthy weight along with regular physical activity may reduce the risk of prostate cancer.

Family history: Prostate cancer appears to have a genetic link. Having a father or brother with the disease doubles a man's risk of developing it. The risk gets even greater if several relatives have been affected, particularly if they were young at the time of diagnosis. The recent discovery of the HPC1 gene will soon give more information about the inherited risk of prostate cancer. Tests to find abnormal prostate cancer genes may one day become available to help identify men at increased risk for developing prostate cancer.

Vasectomy: Men who have undergone vasectomy (a surgical procedure that renders them sterile) may have an increased risk of getting prostate cancer, according to some studies. Findings in this area have been inconsistent. Some studies have shown an increased risk after vasectomy, yet others have not.