Ask the Doctor question: How can I prevent prostate cancer?

Bottom line: While most strategies remain unproven in preventing prostate cancer, eating a low-fat diet and perhaps taking a multivitamin with Vitamin E are reasonable strategies that may offer some benefit.

This is an important question, and here is why. Prostate cancer is the most common cancer in men. By the time you are 60, you have about 60% chance of having prostate cancer, and it goes up from there. Yet even without treatment, your overall chance of dying from prostate cancer is less than 1 out of 25. Because of this big difference between the chance of getting prostate cancer and the chance of dying from it, and the fact that treatments for prostate cancer can be harmful, it is not clear that otherwise healthy men should be checking to see if they have it. There is some evidence, however, that we can prevent prostate cancer. An excellent review of the evidence in this area was recently published (Fleshner and Zlotta, Cancer 2007, Vol 110, Iss 9, p. 1889-1899), and I will summarize it here, adding some comments where helpful.

Taking preventive medicines = uncertain benefit

A testosterone-blocker called finasteride has been shown to reduce the risk of prostate cancer, but in the men who get cancer while taking it, their cancer is a more dangerous type. Anti-inflammatories like aspirin and ibuprofen have unknown benefit, yet often have side effects.

Taking Vitamin E = might reduce risk

Vitamin E seemed to reduce the risk in one study, but this has not been confirmed in other studies. Still, it is probably not harmful and may be helpful to take a daily multivitamin with E in it.

Low-fat diet = probably reduces risk

Avoiding pesticides = might reduce risk

Exposure to pesticides is associated with prostate cancer, but we are not yet sure if avoiding them reduces risk.

Selenium = might reduce risk

Also may increase the risk of skin cancer

Green Tea = conflicting research results

Soy = uncertain benefit

Lycopene = weak evidence of benefit. Not proven.

This is an antioxidant found in tomato products.