Urine trouble: the flow must go on.

Never straying too far from a men's room. Trudging to the bathroom four or five times a night. Always feeling like your bladder isn't quite empty. Really having to go, but not going much when you get the chance.

That's benign prostatic hyperplasia, or BPH. By age 50, one out of every seven men already feels its effects. By age 60, more than half of all men have it. And the figure may be as high as 90 percent for men in their 70's and 80's.

"As men get older, it's very common for them to slowly develop symptoms like frequent urination, an urgent need to urinate, getting up again and again at night to go to the bathroom, dribbling, and a weak urinary stream," says internist Timothy Wilt of the Veterans Administration Hospital in Minneapolis. "Those are classic benign prostate problems."

The good news: Though results from well-designed studies aren't in yet, it looks like some dietary supplements may help as much as drugs ... and with fewer side effects.

Isn't It Swell

The prostate is a chestnut-sized gland that produces the fluid part of semen. Researchers aren't certain why a man's prostate starts to enlarge as he ages, but the process is as common as gray hair.

One theory: Throughout their lives, men produce both testosterone, a male hormone, and small amounts of estrogen, a female hormone. As they age, the testosterone levels in their blood decline, which leaves a higher proportion of estrogen. Animal studies suggest that more estrogen promotes cell growth.

Larger cells means an enlarged prostate. And since the prostate sits like a doughnut surrounding the neck of the urethra (the tube that carries urine out of the bladder), an expanding prostate can pinch off the flow of urine.

Fortunately, benign prostatic hyperplasia (it's also called hypertrophy) is just that: benign. "For the vast majority of men, the problem is bothersome lower urinary tract symptoms, not prostate cancer," says physician Timothy Wilt. "Men with BPH have no greater risk for developing prostate cancer than men without BPH."

Go with the Flow

If you have symptoms of benign prostatic hyperplasia, "the first step should be to see a physician," advises urologist Glenn Gerber, an associate professor of surgery at the University of Chicago. "That's to make sure that it's just BPH and not something else like prostate cancer or a bladder or kidney infection, which requires a different treatment."

If the symptoms don't pose a major inconvenience, the best way to treat BPH may be to leave it alone or try simple lifestyle changes. As many as one-third of all mild cases clear up by themselves.

"I ask my patients about their intake of alcohol and caffeine, which make people urinate more, about how much fluid they drink, and about whether they go to the bathroom before long trips or before going to bed," says Wilt.

If lifestyle changes don't help enough, physicians are likely to recommend drugs or surgery.

"The only permanent solution is surgery," Gerber notes, in the most common procedure, called trans-urethral resection of the prostate (TURP), surgeons "shave" the gland, which helps relieve pressure on the urethra. But the prostate is embedded in a nest of nerves, and if they're damaged during surgery, the result can be incontinence or impotence.

That's one reason why tire number of trans-urethral resections has tailed off dramatically since the 1980's. Another reason: better prescription drugs to treat BPH.

"Alpha-blockers are the drugs most widely shown to improve the symptoms of BPII," says Wilt. They relax the muscles of the bladder and the prostate, which makes it easier to urinate.

Alpha-blockers don't work in everyone, though, and they can cause side effects like dizziness, headache, and postural hypotension (light-headedness after standing up). The most-prescribed alpha-blockers are Cardura, Hytrin, and Flomax.

Another drug, finasteride (Proscar), interferes with the conversion of testosterone to dihydrotestosterone, a hormone that stimulates the prostate to grow. Proscar causes the prostate to shrink, which relieves pressure on the urethra. But the drug takes three to six months to work, and it can cause enlarged or tender breasts, a diminished sex drive, and other side effects.

Some physicians combine Proscar with alpha-blockers. "There's evidence that the two together may not only improve BPH symptoms, but also slow the progression of the disease and reduce the need for surgery in the future," says Wilt.

But two drugs are more expensive than one, the chances of suffering side effects are greater, and you've got to see a doctor to get them--all of which may explain why many men have turned to herbal supplements to help with their enlarged prostates. The two most popular: saw palmetto and pygeum.

* Saw Palmetto. The saw palmetto is a short palm tree indigenous to the Southeastern United States, where Native Americans used its berries to treat urinary problems. Today, manufacturers concentrate the berry's active ingredients by extracting its oil.

"Saw palmetto is the herbal supplement with the best evidence for treating BPH," says Glenn Gerber. (Gerber has received financial support to conduct clinical research trials from a company that markets both saw palmetto and pygeum.)

In fact, in a large study of more than 1,000 men, saw palmetto improved urine flow and other BPH symptoms as well as Proscar (though the drug shrank prostates more than the herb). (1)

That study was one of 21 trials in more than 3,000 men with BPH that were reviewed by the Cochrane Collaboration, a global network of scientists who evaluate medical treatments. (2)

In most of the other studies, the saw palmetto takers were nearly twice as likely as placebo takers to report some relief of their symptoms. Urine flow also improved in the men taking the herb, who averaged five fewer nighttime trips to the bathroom per week.

"Saw palmetto provided mild to moderate improvement in symptoms when compared with a placebo," concludes Timothy Wilt, who led the review. "Side effects were mild and infrequent."

And the case for saw palmetto goes beyond the bathroom. "Probably the most convincing evidence to date that there's really something going on, that it's not just acting as a placebo," says Gerber, "are studies where researchers have biopsied the prostates of men who had been taking saw palmetto or a placebo."

The biopsies showed more withering (atrophy) in the prostate cells of saw palmetto takers (that's good). "It does appear that something is going on at a cellular level, but it's a little unclear exactly how that's happening," Gerber reports.

His conclusion: Taking saw palmetto may relieve some symptoms, "but don't expect much shrinkage of the prostate, like you would get with Proscar."

* Pygeum. Pygeum (pronounced pie-JEE-um) hasn't been as well-studied as saw palmetto. It's manufactured from the bark of a tall evergreen tree native to Africa, where it has traditionally been used to treat urinary problems.

"Pygeum takers were more than twice as likely as placebo takers to report a moderately large improvement in urine flow and other symptoms," says Wilt, who led a Cochrane Collaboration team that evaluated 18 well-designed studies on more than 1,500 men. (3)

But questions remain about both saw palmetto and pygeum.

Says Wilt: "The designs of the studies done so far, the types of outcomes they measured, and the quality of the products that were tested were uncertain enough that we need better studies to really know whether these herbs relieve the symptoms of BPH."

And relieving symptoms is only half the story.

"I think that men and their healthcare providers want to know two things about a potential treatment for BPH," says Wilt. ""First, will it make my current symptoms better within a reasonably short time, say a couple of months to a year? And second, can it prevent those symptoms from getting worse and from requiring surgery in the future?

"We know that alpha-blocker drugs and Proscar can do the first, and it looks like a combination of the two can do the second," Wilt says. "What we don't know for certain yet is if saw palmetto or pygeum can do either, or both."

Two government-sponsored studies, one just ending and the other just beginning, may answer that question. "Both are designed to be comparable in quality to the studies pharmaceutical companies do to get their drugs approved by the Food and Drug Administration [FDA]," says Wilt.

In the meantime, should men with enlarged prostates try herbs?

"I tell my patients who want to take herbs that saw palmetto and pygeum may work and have relatively few adverse effects," says Wilt. "They're probably most appropriate for the average man with BPH who says that his symptoms are bothersome and that he'd like to try something for them, but they're not so bad that he would go to the mat and do almost anything for relief."

The Dosaqe with the Mostaqe

Figuring out how much saw palmetto to take (320 mg a day, according to Wilt), or how much pygeum is enough (100 mg a day), is the easy part. ("Give them at least a month or two to see if they work," says Wilt.)

What's tough is deciding which brand to buy. When it comes to supplements--especially herbs--you can't assume that all brands contain what may work ... or even what the labels claim.

"It's not obvious which supplements are the high-quality products with enough of the active ingredients to help relieve symptoms," says Wilt.

Most studies of saw palmetto used extracts, not the whole or crushed berries that some supplement makers sell. Look for an extract that's at least 85% fatty acids and 0.2% sterols (it should say so on the label).

That's what ConsumerLab.com did last year, when it examined 14 saw palmetto products. (The subscription Web site checks whether supplements contain the dosages listed on their labels.) Only nine of the 14 passed muster. The other five either had too little of the active ingredients or appeared to be contaminated with other oils.

Among the brands that passed: Now, Nutrilite, Puritan's Pride, Spring Valley, and Vitamin World. Price wasn't a measure of quality, since the cheapest ($4 a month) passed, while the most expensive ($20 a month) flunked. (The complete report, including a list of brands that passed and failed, is available at www.ConsumerLab.com to subscribers.)

The simplest approach might be to buy a supplement that contains Sabalselect, the saw palmetto extract used in the two government-funded studies.

Sabalselect, which is manufactured by the Italian firm Indena, is used in a handful of supplements. The only one that identifies it by name, according to Indena, is Swanson Superior Herbs Saw Palmetto 320 mg softgels. (It's available at www.swansonvitamins.com or 800-437-4148.)

As for pygeum, nobody has analyzed commercial products, so you're on your own. Another problem: Pygeum comes from an African tree that has been so extensively harvested for botanical supplements that it is now listed with the Convention on International Trade in Endangered Species. (Saw palmetto is cultivated, not gathered in the wild, so it's not in danger of extinction.)

Go to Plant B

A few other supplements may help relieve the symptoms of BPH. But, as Wilt cautions, "the evidence is much greater for saw palmetto and pygeum than for other products." Among the alternatives:

* Grass Pollen. "Pollens from a variety of grass species have been used in Europe to treat the symptoms of BPH, particularly in the Scandinavian countries," says Glenn Gerber.

Two studies tested a popular European rye-grass pollen extract called Cernilton against a placebo in a total of 165 men for three to six months. (4) "Cernilton modestly improved the overall symptoms of BPH, including the need to get up at night to go to the bathroom," says Wilt.

But it didn't improve urinary flow rates, the degree of bladder emptying, or the size of the prostate. "Additional trials are needed to evaluate its long-term effectiveness and safety," a Cochrane Collaboration review concluded.

What's more, "Just because a particular European brand may work over there doesn't mean that something in a store here labeled 'Pollen Extract' will do the same," cautions Gerber.

* Beta-Sitosterol. Sitosterols are cholesterol-like compounds found in many plants. When consumed in large enough amounts, they interfere with cholesterol absorption. (That's how the cholesterol-lowering margarine Take Control works.) Sitosterols also attach themselves to the prostate gland, and mixtures of plant sterols have been used in Europe to treat BPH. In four studies that followed more than 500 men with BPH for one to six months, "Beta-sitosterol improved the men's symptoms and their urinary flow, compared with a placebo," says Wilt. (5)

* Nettle Root. The roots (not the leaves) of the nettle plant are widely used in Europe to treat BPH. In three small studies, men taking nettle root reported slightly better urine flow than men who were given a placebo.

* Zinc. Dozens of Web sites would be happy to sell you dietary supplements with zinc to treat the symptoms of BPH and shrink swollen prostates. What's their evidence? One study from 27 years ago that didn't use a placebo, so there's no way to tell whether the symptoms really improved. The study was never published or followed up by the researchers.

The Bottom Line

"It's reasonable for a man to try saw palmetto or another herbal supplement once he's sure he doesn't have cancer or anything else more serious than BPH going on," concludes the University of Chicago's Glenn Gerber.

"Once those things have been ruled out, the focus is primarily on the quality of life. And if people get better with herbs, then that's as good as anything else."

(1) Prostate 29: 231, 1996.

(2) Cochrane Database Syst. Rev. 3: CD001423, 2002.

(3) Amer J. Med. 109: 543, 2000.

(4) BJU International 85: 836, 2000.

(5) BJU International 83: 976, 1999.

RELATED ARTICLE: What else could it be?

Difficulty urinating isn't always a sign of benign prostatic hyperplasia (BPH). It could also be:

* Acute Prostatitis: A bacterial infection of the prostate that can occur in men at any age. Symptoms include fever, chills, and pain in the lower back and between the legs. The condition can make it hard or painful to urinate. Doctors usually prescribe antibiotics and recommend more liquids.

* Chronic Prostatitis: A recurring prostate infection. The symptoms are similar to those of acute prostatitis, though usually milder and without fever. The condition is hard to treat. Warm baths sometimes bring relief. In many cases, the problem clears up by itself.

* Prostate Cancer: Some 40,000 men die in the U.S. every year from prostate cancer. In its early stages, the disease often has no symptoms. Advanced prostate cancer can slow or weaken the urinary stream or cause frequent urination. It can also cause blood in the urine or impotence. If advanced cancer has spread to the bones, it can cause pain in the pelvic bone, spine, hips, or ribs. The disease is usually first detected through a digital rectal exam or PSA (prostate specific antigen) test.

Sources: National Institutes of Health and the American Cancer Society.