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B. Individual Components

Table A contains a list of the known components in extracts of saw palmetto fruit. Some components are common in many other plants and are widespread in the human diet. The components of extracts of saw palmetto fruit are commonly categorized as hexane extractable (i.e., phytosterols, phenolic components, free fatty acids, ethyl esters of fatty acids, and other lipid components), ethanol extractable (i.e., polyprenoids, flavonoid components, phenolic glycosides, and fatty alcohols), or water soluble (i.e., commonly found sugars and unique high-molecular-weight acidic polysaccharides). A hexane extract of saw palmetto fruit is the preparation that has been used most commonly in clinical trials. The hexane extract of saw palmetto fruit is unusual for a plant extract in that is has a very high content of medium-chain fatty acids and a high proportion of fatty acids present as ethyl esters.

C. Description of Dietary Supplement Preparations and Amounts Ingested in Ordinary Use

Saw palmetto is sold in several forms with lipid/sterol and “oily” extracts of the dried fruit being the most common forms on the market. A lipid/sterol extract of saw palmetto fruit (LESP) can be prepared by extraction with n hexane (100 percent), extraction with ethanol (70–95 percent, w/w), or by supercritical fluid extraction with liquid carbon dioxide. LESPs are somewhat quantifiable or standardized by total fatty acid content (usually 70–95 percent, w/w) or other components (USP, 2000). LESPs are commonly sold as capsules or tablets of a dried powder of the extract and in blended preparations where the powdered extract is combined with other ingredients, typically other powdered botanical extracts. Other forms of saw palmetto that may be available include powdered dried fruit (usually available in capsule or tablet form), dried whole fruit or preparations of the fruit (used in making a tea or water extract), tinctures (extracts made with aqueous ethanol as the solvent), and other liquid extracts.

In numerous clinical trials, the typical dose of saw palmetto for a subject with symptomatic benign prostatic hyperplasia (BPH)2 was 320 mg


BPH is a nonmalignant enlargement of the prostate from excessive proliferation, which causes nodules of the prostate gland to enlarge around the urethra, eventually limiting urinary flow from the bladder. Throughout life, dihydrotestosterone (DHT) directly stimulates the growth of the epithelial and stromal cells of the prostate. In aging men, the prostate is more responsive to androgen stimulation and the gland increases in size, causing urinary symptoms. Symptoms include difficulty in starting or stopping urine flow, a need to urinate frequently (especially at night), and a feeling of urgency-to-urinate. Urinary tract infections and urinary obstruction are common.

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