Enlarged Prostate Patients may not Benefit Saw Palmetto - Herbal Supplement Tested

February 9th 2006

Saw Palmetto

New research indicates that the herbal extract saw palmetto was no more effective than the placebo for improving urinary symptoms in men with enlarged prostate. Researchers led by Stephen Bent, MD, a staff physician at the San Francisco VA Medical Center, and Andrew Avins, MD, MPH, of the Northern California Kaiser Permanente Division of Research, conducted a double blind study involving 225 men.

The researchers randomly assigned patients with enlarged prostates a placebo or saw palmetto. They took the tablets twice per day for one year.

The subjects were tested for symptoms and side effects. The symptoms were assessed according to a standard symptom score for benign prostate hyperplasia (BPH) and objective measures of urinary function.

Stephen Bent, who is also a professor of medicine at the university of California, San Francisco, said “If you look at the change in symptoms over time between the two groups, it was almost identical. There was no statistically significant difference at any time point during the study."

They also divided the men into subgroups. These groups included men with more and less severe symptoms and those with larger and smaller prostates. Here again, they found no difference in any of the subgroups. The effects of the placebo and saw palmetto were the same.

Saw palmetto is used by an estimated 2 million men in the US, according to a University of San Francisco press release. According to the National Institutes of Health, BPH affects more than 50 percent of the men over 60 and upwards of 90 percent of the men over 70.

The results were surprising because earlier studies found saw palmetto beneficial. Bent said “"Prior studies were generally small in size and short in duration. Plus, the vast majority of them did not use the standard symptom score that we used for assessing the severity of BPH."

It is unknown whether patients would benefit from other dosages. Bent said “whether other doses, formulations, or patient populations might respond differently is unknown."