Prostate Cancer Although most men develop latent prostate cancer with advancing age, such prostate tumors remain small, are confined within the prostate gland, and do not cause symptoms. The incidence of small, localized prostate cancers is roughly similar in young men around the world, but evolution of those cancers to more aggressive, symptomatic disease occurs as men age at a higher rate in western nations than among men living in Asia. Prostate cancer is especially aggressive among African-Americans, although the reasons for this are unknown. Dietary Fat Most research on diet and prostate cancer has focused on prostate cancer incidence. Dietary factors that are associated with reduced prostate cancer incidence might also reduce the rate of prostate cancer growth after diagnosis, thus preventing or slowing progression of early-stage prostate cancer. High intake of foods from animal sources, especially foods high in saturated fat, have been associated with increased prostate cancer risk.45 High-fat diets can also increase testosterone levels, which may account for their apparent stimulatory effect on prostate cancer growth.166,167 Consumption of a diet high in saturated fats has also been linked to heart disease. Older men with early-stage prostate cancer are actually at higher risk of death from heart disease than from prostate cancer, so it is especially wise for prostate cancer survivors to follow a heart-healthy diet that is low in saturated fat, high in fruits and vegetables, and accompanied by regular physical activity. Lycopene Lycopene, the red-orange carotenoid antioxidant found at high levels in vegetables such as tomatoes and tomato-based foods, is commonly recommended for prostate cancer survivors. This recommendation comes from epidemiologic research suggesting that diets high in tomato products might be associated with lower prostate cancer incidence.168-170 Although lycopene may indeed be beneficial for the prostate, this hypothesis is not documented and requires further study. Even if lycopene in a healthy diet is associated with lower risk for prostate cancer, it does not follow that high doses would be either more effective than the lycopene in the diet or that high doses of a supplement would be safe. Many studies have shown dietary levels of beta carotene to be associated with lower risk for lung cancer, but two trials using high-dose supplements of beta carotene have now shown that high dose supplements actually increase (not decrease) the rate of occurrence of lung cancer.106,107 High doses of single nutrients taken as supplements appear to be capable of interfering with normal nutritional processes to increase cancer risk. Selenium Selenium is a trace mineral that has been thought to reduce prostate cancer risk. In a randomized controlled trial for skin cancer prevention, selenium supplementation with 200 mcg per day had no effect on skin cancer, but it did reduce prostate cancer incidence.171 Whether this was a chance finding or a true beneficial effect is unknown. Another study has also found that men with the highest level of selenium (measured by toenail selenium content) had a reduced risk of advanced prostate cancer compared with the group with the lowest selenium levels.172 At this point, selenium supplementation cannot be recommended with confidence, but if a selenium supplement is used, it would be prudent to limit the dose to 200 mcg per day. The best source of selenium in supplement form is in a selenium-enriched brewer’s yeast rather than inorganic selenium (e.g., selenite), because the latter is more likely to cause hepatic and brain toxicities at high doses. Vitamin E In the Alpha Tocopherol and Beta Carotene (ATBC) Study, which was designed principally to test the effects of beta carotene and/or vitamin E (alpha tocopherol) supplementation on lung cancer risk, the men who were assigned to take vitamin E (50 mg per day) had a lower incidence of prostate cancer than did the men taking a placebo.173 Increased consumption of foods rich in vitamin E or supplements may decrease the rate of conversion from latent to aggressive forms of prostate cancer, but confirmatory studies are needed. Importantly, though, total mortality was not lower among those taking vitamin E—actually it was a bit higher due to episodes of bleeding and hemorrhagic strokes. Whether vitamin E may decrease the rate of conversion from latent to aggressive prostate cancer is still unknown, and the risk/benefit ratio of taking supplementary vitamin E for cancer prevention is uncertain.174 It would be prudent to limit the intake of vitamin E to 400 to 800 mg per day if supplements are used. Examples of foods rich in vitamin E include wheat germ, green leafy vegetables, seeds, nuts, and vegetable oils. A large prostate cancer prevention trial (SELECT) is now underway to test the ability of vitamin E (400 mg per day) and/or selenium (200 mcg per day) to reduce prostate cancer risk.175 Soy As soy protein products contain active phytoestrogens (such as isoflavones), increased consumption of soy foods, such as tofu, soy milk, and other soy-containing foods, is commonly recommended for prostate cancer survivors. There have been no good studies of the effects of soy or other phytoestrogens, however, on the growth of prostate cancer after diagnosis of advanced disease, but trials are currently underway. Calcium Some epidemiological studies have shown that men who have high levels of calcium in their diets might be at increased risk for prostate cancer incidence.176 Calcium, especially when taken as supplements, has the ability to temporarily suppress circulating levels of vitamin D in the blood. Because vitamin D is thought to be important in decreasing the growth of prostate cells, it is hypothesized that high levels of calcium in the diet, including from calcium supplementation, might increase prostate cancer risk. The possible effects of calcium after prostate cancer treatment, however, are unknown at this time. During treatment of prostate cancer, it is important to eat a healthy diet that meets the additional nutritional needs caused by surgery, chemotherapy, or radiation therapy. It is also important that prostate cancer survivors tell health care providers which vitamin, mineral, or herbal supplements they might be taking, as some may interfere with treatment. Remember we are NOT Doctors and have NO medical training. This site is like an Encylopedia - there are many pages, many links on many topics. Support our work with any size DONATION - see left side of any page - for how to donate. You can help raise awareness of CAM.