Saw palmetto

About Saw palmetto

A liposterolic extract of the berry of a Florida palm, standardised to 85–95% fatty acids and sterols. It is the most-sold botanical for prostate symptoms.

Saw palmetto is the clearest example of early positive results not surviving better trials. Two large, well-conducted US randomised trials — including one escalating to triple the usual dose — found no difference from placebo in urinary symptom scores, and the Cochrane review concluded it is no better than placebo for benign prostatic hyperplasia. European trials of one hexane extract are more favourable and are the basis for its continued licensing there, which is a live disagreement rather than a settled question.

Sold as

Liposterolic extract softgel, Hexanic extract, Dried berry capsule, Tea

Standardised to

Trials used extracts standardised to 85–95% fatty acids and sterols — a product without this marker may not resemble what was studied.

Also known as

Serenoa, Permixon, Sabal, American dwarf palm

Regulation: Licensed as a medicine for lower urinary tract symptoms in several European countries, where a specific hexanic extract is used. In the US it is a supplement, and the two largest US trials found no benefit.

What the research used

The amounts, forms and durations published trials of Saw palmetto actually administered.

When it was taken

Each window says whether a trial compared it against an alternative, or whether it is convention and pharmacology. Most timing advice is the second kind.