Complementary and alternative medicine (CAM) is a form of treatment used to supplement or replace standard treatments.CAM is not generally considered a standard of care. Although CAMs lack the long, cumulative, meticulous and rigorous research process of standard medical treatments, recent reports confirm that they are indeed safe and effective. CAM is more commonly used in patients with prostate cancer. CAM therapies used by prostate cancer patients include certain foods, dietary supplements, herbs, vitamins and minerals. Surveys have shown that about 40% of prostate cancer patients in the United States use CAM, most often including saw palmetto extract, vitamin E and selenium; Canadian surveys have found that 30% of patients use CAM, most often with vitamin E, saw palmetto extract and lycopene; 25% of patients in the United Kingdom use CAM, most often with a low-fat diet, vitamins and lycopene. The vast majority of patients use CAM for the primary purpose of strengthening the immune system, preventing recurrence and improving quality of life. Foods and nutrients can not only reduce the risk of prostate development and progression, but can also reduce some of the symptoms of prostate cancer and alleviate the side effects of treatment.