Serenoa repens, the saw palmetto, is the sole species currently classified in the genus Serenoa. It has been known by a number of synonyms, including Sabal serrulatum, under which name it still often appears in alternative medicine. It is a small palm, normally reaching a height of around 2–4 m (3–6 ft). Its trunk is sprawling, and it grows in clumps or dense thickets in sandy coastal lands or as undergrowth in pine woods or hardwood hammocks. It is endemic to the southeastern United States, most commonly along the Atlantic and Gulf Coastal plains, but also as far inland as southern Arkansas. It is a hearty plant; extremely slow growing, and long lived, with some plants, especially in Florida, possibly being as old as 500-700 years.
Saw palmetto fruit (berry) is a large reddish-black drupe and is an important food source for wildlife and historically for humans. It contains constituents such as fatty acids, steroidal saponins, phytosterols, volatile oil, resin, tannins. Saw Palmetto berries contain an oil with a variety of fatty acids and phytosterols. These fatty acids include capric, caprylic, caproic, lauric, palmitic, and oleic acid and their ethyl esters. The major phytosterols are beta-sitosterol, stigmasterol, cycloartenol, stigmasterol, cycloartenol, lupeol, lupenone, and 24-methyl-cyclo-artenol.
The fruits of the saw palmetto are highly enriched with fatty acids and phytosterols, which were used traditionally as a general tonic to nourish the body and encourage appetite and normal weight gain. The berries were also used in the treatment of genito-urinary tract problems including enuresis, nocturia, and urinary tract disorders. And it was used for remedy for atrophy of the testes, impotence, inflammation of the prostate, and low libido in men. And it was used as a tonic and expectorant for mucous membranes, particularly the bronchial passages. Recent clinical trials have shown that saw palmetto berries are helpful in the treatment of benign prostatic hyperplasia.
The Saw Palmetto Extract used in dietary supplements is derived from the fruits of the plant Serenoa repens.