Saw palmetto extract does not reduce UT symptoms, study finds

October 11, 2011

Researchers found saw palmetto extract did not reduce urinary tract symptoms in 369 men with benign prostatic hyperplasia, a study reported recently in JAMA.

Saw palmetto extract did not reduce urinary tract symptoms in patients with enlarged prostate, reported a study published recently in the Journal of the American Medical Association.

Researchers at 10 U.S. sites and 1 Canadian site conducted a randomized study of 369 men with benign prostatic hyperplasia (BPH) who were 45 years of age and older. Some received saw palmetto extract at a standard dose of 320 mg per day for 24 weeks, then a double dose for the next 24 weeks, and a triple dose for the last 24 weeks. The other patients received a placebo for 72 weeks.

Researchers found no difference in the percentage of patients who had at least a 3-point drop in symptom scores. From baseline to 72 weeks, the mean American Urological Symptom Index (AUASI) scores dropped by 2.20 points for men taking escalating doses of saw palmetto extract. At the same time, the AUASI scores for men taking the placebo dropped 2.99 points.

“Increasing doses of a saw palmetto fruit extract did not reduce lower urinary tract symptoms more than placebo,” wrote the researchers from Northwestern Memorial Hospital in Chicago. No adverse effects were identified with saw palmetto.

While a 2002 Cochrane review found that saw palmetto extracts significantly reduced nocturia and improved peak uroflow measures, more recent studies have questioned the efficacy of saw palmetto for treatment of BPH.