Saw Palmetto

An ancient herbal remedy for urinary problems, saw palmetto (Serenoa repens) is now popular as a supplement for prostate health—and for good reason. Some studies (most of them small) have shown that shown that saw palmetto—extracted from the dark purple berries of the American saw palmetto plant—may help treat benign prostatic hyperplasia (BPH), the medical name for an enlarged prostate gland. BPH is an overgrowth of cells in the prostate that may be due to changes in hormone levels that occur with age. It affects many men over age 40, and more than half of men over 60. BPH is not cancer, nor does it cause cancer. But an enlarged prostate that presses on the urethra (the tube that carries urine from the bladder) can interfere with urination. The first line of treatment is usually a prescription drug, such as finasteride (Proscar). Some people believe saw palmetto is as good as the drugs for BPH, or even better.

Claims, purported benefits: Shrinks the prostate; reduces symptoms of BPH, such as urgent or frequent urination or urinary leaking. Other claims are made with little or no evidence—for example, that saw palmetto helps treat baldness, low libido, bladder disorders, prostatitis, and migraines.

Bottom line: If you have urinary symptoms and want to try saw palmetto, talk to your doctor first. You need to make sure what you have is BPH. Be cautious about taking saw palmetto if you have a bleeding disorder or are taking blood thinners (such as warfarin). It may also not be safe to take saw palmetto with finasteride or some other prescription drugs for BPH. If you try saw palmetto, be patient—as with finasteride, you may not notice a benefit for several months. Much good research on saw palmetto has been positive—but some studies have found no benefit. There’s no guarantee that saw palmetto products in the U.S. are equivalent, even if they are "standardized." No one knows what an optimal dose of saw palmetto is, but the amount typically used in studies is 320 milligrams a day (in a single or split dose).