Can prostate cancer be prevented?

The exact cause of prostate cancer is not known, so it is not possible to prevent most cases of the disease. But based on what we do know, there are some things you can do that might lower your risk of prostate cancer.

Body weight, physical activity, and diet

The effects of body weight, exercise, and diet on prostate cancer risk are not clear, but there may be things you can do that might lower your risk.

Some studies have found that men who are overweight may have a slightly lower risk of prostate cancer overall, but a higher risk of prostate cancers that are likely to be fatal.

Studies have found that men who get regular exercise have a slightly lower risk of prostate cancer. Vigorous activity may have a greater effect, especially on the risk of advanced prostate cancer.

Several studies have suggested that diets high in certain vegetables (including tomatoes, cruciferous vegetables, soy, beans, and other legumes) or fish may be linked with a lower risk of prostate cancer, especially more advanced cancers. Cruciferous vegetables include cabbage, broccoli, and cauliflower.

For now, the best advice about diet and activity to possibly reduce the risk of prostate cancer is to:

• Eat at least 2½ cups of a wide variety of vegetables and fruits each day.
• Be physically active.
• Stay at a healthy weight.

It may also make sense to limit calcium supplements and to not get too much calcium in the diet.

For more information, see our document, American Cancer Society Guidelines on Nutrition and Physical Activity for Cancer Prevention.

Vitamin, mineral, and other supplements

Some earlier studies suggested that taking supplements of vitamin E or the mineral selenium might lower prostate cancer risk. But in a large study (known as SELECT), neither vitamin E nor selenium was found to lower prostate cancer risk. In fact, men taking the vitamin E supplements were later found to have a slightly higher risk of prostate cancer.

Several studies are now looking at the possible effects of soy proteins (called isoflavones) on prostate cancer risk. The results of these studies are not yet available.

Taking any supplements can have both risks and benefits. Before starting any vitamins or other supplements, talk with your doctor.

Medicine

Large studies have looked at 2 drugs used to treat benign prostatic hyperplasia (BPH), finasteride (Proscar^®) and dutasteride (Avodart^®), to see if they might also help lower prostate cancer risk. In these studies, men taking either drug were less likely to develop prostate cancer after several years than men getting a placebo.

But in men who took these drugs, there were more cases of prostate cancer that looked like they might grow and spread quickly. Researchers are still watching the men in these studies to see if this had an effect on how long the men live.

These drugs can cause sexual side effects like lowered sexual desire and impotence. But they can help with urinary problems such as trouble urinating and leaking urine (incontinence).At this time it's not clear whether taking these drugs to lower the risk of prostate cancer is a good idea or not. Men who want to know more about this should discuss it with their doctors.

Other drugs that may help prevent prostate cancer are now being tested in clinical trials. So far, no other supplement or drug has been found to be helpful in studies large enough to allow experts to recommend they should be given to men.