Men’s health centre

Saw palmetto 'no benefit as prostate remedy'

28th September 2011 - Men with urinary problems related to an enlarged prostate who received doses of the fruit extract saw palmetto did not experience a reduction in their symptoms, a study has found.

One UK charity said a lack of science regarding the control of enlarged prostate symptoms had led to men turning to alternative therapies, but that new treatments were now available.

Enlarged prostate

An enlarged prostate gland, also known as benign prostatic hyperplasia (BPH), is a common condition which affects men as they get older. Around 60% of men who are aged 60 or more have some degree of prostate enlargement.

Although the condition is not usually a serious threat to health, an enlarged prostate can put pressure on a man's bladder and the urethra, the tube through which urine passes. This can give rise to a number of irritating symptoms including difficulty starting to urinate, a frequent need to pass urine and difficulty emptying the bladder fully.

The extract of the fruit of the saw palmetto dwarf palm tree (Serenoa repens) is used in Europe and the US by men hoping to reduce the symptoms of an enlarged prostate. Some products containing  saw palmetto are registered with the Medicines and Healthcare products Regulatory Agency (MHRA) under the Traditional Herbal Registration (THR) scheme. Several recent trials have questioned its effectiveness in easing lower urinary tract symptoms (LUTS). In the latest study, US researchers report that men who took saw palmetto in increasing doses were no more likely to see a reduction in symptoms than those who took a placebo (an inactive treatment).

The trial

Dr Michael Barry of Massachusetts General Hospital, Boston, and colleagues conducted a study to determine if boosting intake of saw palmetto to up to three times the standard daily dose would improve LUTS attributed to an enlarged prostate.

The randomised trial was conducted at 11 North American clinics over a 28-month period and involved 369 men aged 45 or older who had the condition and a peak urinary flow of at least 4 mL/s (millilitres per second).

Half of the men enrolled in the trial received a standard daily dose of saw palmetto extract (320 mg). The remainder were given a placebo capsule. The dosage for both groups was increased to double and then triple over a 72-week period.