Prevention
Selenium and vitamin E. Selenium has been shown to decrease the incidence of prostate cancer in men by more than 60 percent. Researchers found that vitamin E decreased the risk of developing prostate cancer by 32 percent. However, much longer studies are needed given the length of time prostate cancer takes to develop.

Lycopene. Men with diets rich in lycopene, found in tomato products, watermelon, and pink or red grapefruit, seem to have lower incidences of prostate cancer, possibly because lycopene, as a proven antioxidant, protects DNA and inhibits cancer growth.

Vitamin D. Vitamin D, which is produced naturally when the body is exposed to sunlight and may also be taken in supplement form, has been shown to decrease prostate cell replication. This may be one of the reasons prostate cancer is more prevalent in cloudier locales, such as Seattle, than in sunny San Diego.

Other supplements. Melatonin, saw palmetto (Serenoa repens), vitamin C, and zinc are also sometimes prescribed for reducing prostate cancer risk.

Treatment
Many doctors increase daily doses of the supplements listed above, and recommend the following:

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• Modified citrus pectin. Studies have shown that modified citrus pectin, or fractionated citrus pectin, can inhibit cancer metastasis by up to 90 percent.
• Chinese herbs. A variety of Chinese herbs are used to counter hot flashes and other symptoms associated with hormone therapies.
• Glutamine. Glutamine is used to soothe internal pain related to radiation therapy.
• Other supplements. Curcumin, milk thistle (Silybum marianum), and combinations of vitamins C and K are also often recommended.

—J.W.

Sources: Paul Reilly, ND, LAc, staff physician at the Seattle Cancer Treatment & Wellness Center; Durado Brooks, MD, MPH, director of prostate and colorectal cancer for the American Cancer Society; and Thomas A. Kruzel, ND, former president of the American Association of Naturopathic Physicians.