Saw palmetto

Saw palmetto can improve men’s symptoms

The Irish Times
Health Supplement, p. 13
20 May 2008

Prostate problems can be alleviated by saw palmetto, writes Dónal O’Mathúna .

RECENT ATTENTION to men’s health issues, and prostate cancer in particular, is to be welcomed. The prostate gland can become enlarged in ways that are not cancerous.

This occurs in a few per cent of men in their late 40s, but about one-quarter of men in their 80s have the condition. Because the prostate is wrapped around the urethra at the base of the bladder, prostate problems cause difficulties with urination.

The symptoms range from embarrassing and irritating, to very painful conditions that can lead to serious problems.

A number of herbal remedies have reputations in promoting prostatic health. The most popular is saw palmetto for benign prostatic hyperplasia (BPH).

This condition can be difficult to diagnose as its symptoms are similar to those arising from other problems with the prostate, bladder or urinary tract. The most common symptoms are a frequent desire to urinate, especially during the night, but then having difficulty urinating.

Saw palmetto is also called the American dwarf palm tree and is native to US southeastern coastlands and the West Indies. Its scientific name is Serenoa repens, but it has other scientific and common names. The most widely used herbal remedy is a fat-soluble extract of its blue-black berries.

Evidence from studies

A Cochrane review of the evidence for saw palmetto found 11 studies of its use for BPH. Cochrane reviews are independent evaluations of a wide range of healthcare interventions. They are available free from any internet connection in Ireland thanks to funding from the Health Research Board (

The 2002 review found that men taking saw palmetto had mild to moderate improvements in urinary symptoms.

Studies comparing saw palmetto with pharmaceutical treatments found similar subjective improvements with saw palmetto having fewer side effects, but the prostate size was reduced only by pharmaceutical drugs.

Few studies have compared saw palmetto with a placebo, with is an important limitation. BPH and other urinary tract conditions are strongly influenced by the placebo effect because measurements of urinary symptoms and “performance” are very subjective. Thus, two recent, relatively large studies that lasted one year found saw palmetto no better than placebo in objective and subjective measurements of BPH symptoms.

Problematic aspects

The adverse effects of saw palmetto are generally mild and less problematic than pharmaceutical medications. The most common side effects of saw palmetto are dizziness, headache and complaints such as nausea, vomiting or constipation.

There is no evidence that saw palmetto is beneficial for women, and it should not be taken by women of child-bearing age because it contains plant hormones that could interfere with pregnancy.

Self-medication with a herbal remedy can become problematic if it distracts someone from pursuing well-established health strategies.

While BPH is not believed to lead to prostate cancer, men with prostate cancer often have BPH as well. There is no evidence that saw palmetto treats pancreatic cancer. Large population studies have found that men taking saw palmetto do not have a reduced risk of developing prostate cancer.

Anyone at high risk of prostate cancer should not rely on saw palmetto to prevent cancer and should seek medical advice.


A group of pharmaceuticals called alpha blockers effectively relieve the subjective symptoms of BPH and reduce enlarged glands. These should be viewed as the first line of treatment. Men who experience adverse effects from these medicines could consider a trial of saw palmetto, but only after discussions with healthcare professionals. Given that saw palmetto has few side effects, it may provide relief for some men with BPH.
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