Can Herbs Help an Enlarged Prostate?


It’s almost a given that as men age, they develop prostate enlargement and are increasingly plagued by a frequent need to urinate. A walnut-sized gland located below the bladder, the prostate is important in sexual function, providing much of the seminal fluid that carries sperm. With advancing age, prostate cells proliferate-a condition called benign prostatic hyperplasia (BPH), which causes the gland to grow slowly and press on the bladder and part of the urethra. The obstruction caused by the enlarged prostate can prevent the complete emptying of the bladder, so it fills more quickly. The result: a recurrent urge to urinate but difficulty doing so. Half of all men have symptoms of BPH by age 60, and the rate rises to 9 out of 10 over age 70.

The condition, also known as benign prostatic enlargement (BPE), can be a real hassle, so much so that men will try almost anything to relieve it. No wonder vitamin shops, health food stores, and drugstores have shelves filled with dietary supplements for “men’s health,” which often means prostate care.

Remedies for urinary urgency caused by BPH have been around for thousands of years-long before people knew about the function of the prostate. Practitioners of traditional Chinese and Japanese medicine use many herbs to treat urinary symptoms.

Today, almost three dozen plant compounds are used in an attempt to manage BPH, according to a review paper in the Canadian Journal of Urology in 2015. In European countries such as Germany, France, and Austria, phytotherapeutic (that is, plant-based) products are considered the first-line treatment for mild to moderate urinary symptoms of BPH. Some of these are proprietary formulas for which the manufacturers have sponsored research, making comparisons with other products difficult.

Here’s a look at some of the most commonly promoted prostate herbs.

Saw palmetto

This herbal extract comes from the purple berries of the American saw palmetto plant (Serenoa repens). It may help shrink the prostate and improve urinary symptoms, in part, by reducing the activity of the enzyme 5-alpha-reductase, which is how drugs like finasteride and dutasteride work.

One of the best studies, published in the Journal of the American Medical Association in 2011, tested several doses of a standardized extract in 369 middle-aged men over a 72-week period. Even at three times the standard 320-milligram dose, saw palmetto did not reduce prostate symptoms. An updated review by the Cochrane Collaboration in 2012 looked at 32 clinical trials on men with BPH and concluded that saw palmetto didn’t improve urine flow, nighttime urination, or other symptoms compared to a placebo. Another review by the same authors that year, in BJU International, looked at 17 trials on saw palmetto products and again found no benefits. It noted, however, that it was unclear whether this was true of standardized proprietary products.

Indeed, one difficulty in evaluating saw palmetto (like other herbs) is the lack of standardization in most products, meaning that active compounds (notably sterols, fatty acids, and flavonoids) vary considerably. This is partly due to different extraction methods. Among the most studied extracts is a French proprietary product called Permixon, which the European Medicines Agency (something like our FDA) has concluded is effective and safe; however, it found insufficient evidence to support the use of other extracts.

Be cautious about taking saw palmetto if you have a bleeding disorder or are taking blood thinners, though a 2014 review article on the effect of various herbs on warfarin concluded that an interaction is “doubtful.” Do not take it prior to surgery-it may increase bleeding. Despite concerns that saw palmetto may deceptively lower results of PSA tests (for prostate cancer), a 2013 study found no such effect. Don’t take it if you are allergic to plants in the Arecaceae (palm tree) family.

If you have been taking saw palmetto supplements and your symptoms have improved, you may want to continue taking them, but let your doctor know. If you still experience urinary tract symptoms after using saw palmetto for 90 days, ask your doctor about other treatment options.

Beta sitosterol and other plant sterols

Among the key compounds in saw palmetto is beta sitosterol, a phytosterol (plant sterol) that is marketed on its own and in various prostate formulas. Found in many fruits, vegetables, soybeans, seeds, nuts, and other plant products, phytosterols are related to the cholesterol found in animal (including human) cells and, when consumed in large amounts, help lower blood cholesterol by blocking cholesterol absorption in the intestine. Plant sterols also have effects on the hormone system and the prostate.

The last Cochrane review, back in 1999, looked at four large, well-designed clinical studies and concluded that beta sitosterol may help relieve the urinary symptoms caused by BPH but that research into long-term effects was still needed. Research since then has not always upheld these positive findings. In an article in Reviews in Urology in 2009, researchers from the Cleveland Clinic and other urology centers concluded that “nutraceuticals” (including beta sitosterol) had shown some potential in treating BPH and other prostate disorders, but warned that such herbal preparations “may have drastically different composition, durability, contaminants, and even efficacy.”

Beta sitosterol should be used with caution by people who have diabetes or bleeding disorders or are taking blood thinners, testosterone therapy, or drugs that affect blood sugar.

Another herbal extract containing phytosterols and marketed for prostate health is African wild potato (Hypoxis rooperi, a member of the lily family). It is sold in Germany and some other countries under the brand name Harzol. However, there is insufficient evidence to assess its efficacy.

The bottom line

If you have urinary symptoms, talk with your doctor to make sure the cause is BPH and not some other condition. If it is BPH and you need help with it, discuss the pros and cons of prescription medications. These do alleviate symptoms, and their potential adverse effects are well understood. We advise avoiding herbal products, since they are of unproven value, and you usually can’t be sure of what’s really in the bottles. If you still want to try herbal supplements, keep in mind that they are, at best, something of a crapshoot. Better clinical trials are needed to determine which ones, if any, are effective and at what doses, as well as to better evaluate side effects and interactions with drugs and other supplements. At this point, it’s impossible to make comparisons among the various products, particularly because of the different extraction methods and formulations, as well as the general lack of standardization. Beware of combining prostate supplements or taking them with BPH drugs.