Q. My brother needed surgery for an enlarged prostate at age 60. I'm just a few months shy of my 50th birthday, and my urine stream is starting to slow down a bit. Is there anything I can do to avoid following in my brother's footsteps?

A. Prevention is the best medicine. However, in the case of the prostate, although many effective treatments are available, the role of prevention is less certain.

Lifestyle seems to influence the risk of prostate cancer. Diet holds the best hope for prevention. That means a low intake of saturated fat and a generous intake of whole grains; fish; vegetables such as broccoli, cauliflower, and tomatoes (especially cooked tomatoes); and possibly soy. It seems wise to avoid a high consumption of calcium and of alpha-linolenic acid, the omega-3 fatty acid found in canola oil and flaxseeds. Staying lean should reduce risk. Although the evidence is mixed, some studies suggest exercise may help. Supplements of vitamin D hold some promise, but more research is needed. Supplements of selenium and vitamin E are not helpful.

Benign prostatic hyperplasia (BPH) is even more common than prostate cancer, but evidence for prevention is even less secure. Studies have linked BPH with obesity, high blood pressure, lack of exercise, and cigarette smoking. If you attend to these lifestyle elements, your general health will benefit even if your prostate doesn't. Similarly, low to moderate alcohol intake appears to reduce the risk of both BPH and heart disease, while heavy drinking has the opposite effect (to say nothing of its toxic effects on the liver, the nervous system, and psychosocial function). In some studies, coffee has been linked to an increased risk of BPH, but the data are preliminary at best.

Drugs that inhibit the enzyme 5-alpha reductase shrink the prostate by reducing the conversion of testosterone to dihydrotestosterone, the male hormone that stimulates the prostate. Finasteride (Proscar, generic) and dutasteride (Avodart) may have a role in prevention for select men with particular needs, but nothing in your history puts you in that category.

Prevention first? Not for the prostate -- or, at least, not yet for BPH.

-- Harvey B. Simon, M.D., Editor, Harvard Men's Health Watch

(c) 2009 Harvard Health Letters