Saw palmetto berries contain the plant’s active ingredients, which are fatty acids. The plant’s berries can be made into tea. Saw palmetto is also available as tablets, capsules, and a liquid extract. (See also Overview of Dietary Supplements.)
Saw palmetto opposes the actions of testosterone. Many men take saw palmetto to treat benign enlargement of the prostate gland (benign prostatic hyperplasia). In a number of studies, saw palmetto relieved the symptoms of an enlarged prostate gland, such as frequent urination. Although well-designed studies did not show any benefit from saw palmetto for those symptoms, some evidence suggests that a specific chemical extracted from saw palmetto decreases night-time urination and improves urine flow.
Claims that it increases sperm production, breast size, or sexual vigor are unproved.
The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.
National Institutes of Health (NIH), National Center for Complementary and Integrative Health: General information on the use of saw palmetto as a dietary supplement