Yes. Race is another major risk factor. In the United States, this disease is much more common in African American men than in any other group of men. It is least common in Asian and American Indian men. A man's risk for developing prostate cancer is higher if his father or brother has had the disease.  Diet also may play a role. There is some evidence that a diet high in animal fat may increase the risk of prostate cancer and a diet high in fruits and vegetables may decrease the risk. Studies to find out whether men can reduce their risk of prostate cancer by taking certain dietary supplements are ongoing.