Saw palmetto is an herbal supplement which is used most often to treat problems of the prostate, so its primary beneficiaries are men ages 40 and up. The type of extract is the most significant factor used to determine the appropriate saw palmetto dosage. With a standardized extract, which contains 80 to 90% fatty acids, the typical dosage is 320 mg once daily or 160 mg twice daily. The dosage for a non-standardized extract which contains only about 25% fatty acids is 400 mg twice daily. The extract in a pill form is the most common saw palmetto dosage, but it is also available as a pure ground powder.

Also known as serenoa repens, saw palmetto is an extract of the berries of the saw palmetto tree, which grows in southeastern North America, primarily in the state of Florida. Fatty acids are thought to be the most beneficial part of the berry. The percentage of fatty acids in the extract is used to determine the appropriate saw palmetto dosage. The higher the percentage of fatty acids, the lower the dosage required.

In cases where the type of extract or the percentage of fatty acids is not listed, the label of the product should determine the appropriate saw palmetto dosage. One such supplement lists instructions to take two 500-mg tablets every day, for a total of 1,000 mg daily. Users must be careful, however, not to use too much. This is not a case of "more is better," since higher doses of saw palmetto might interfere with the detection of prostate-specific antigens which are important in spotting prostate abnormalities early.

Since saw palmetto is not a medicine, but an herbal supplement, its dosage is not always governed by regulatory agencies, such as the Food and Drug Administration in the US. Although clinical studies have shown some positive results from the use of saw palmetto, the performance of the supplement has not been verified by medical research. Not only is there no proven way to determine the appropriate saw palmetto dosage, there is no guarantee of its effectiveness.

Since strict quality control guidelines are not always in place for saw palmetto, the purity and potency of the supplement can also come into question. It is important to find a reliable manufacturer with a proven track record. In the arena of herbal supplements, not every country has governing agencies to ensure the product lives up to the standards on the label.