Saw Palmetto

Last Updated: September 28 2022

Saw Palmetto is a fatty acid mix from Serenoa repens that has been touted for its abilities to increase testosterone (not effective) and suppress prostate growth (questionable effectiveness); safe for use in benign prostatic hyperplasia and abnormal urine flow rates in men, but studies have had mixed results in terms of efficacy.

Saw Palmetto is most often used for


Saw Palmetto is a supplement which is derived from the fruit of the plant Serenoa repens. The supplement (saw palmetto) has a caloric value, as it is rich in fatty acids.

Compounds in saw palmetto have the ability to block an enzyme that converts testosterone into dihydrotestosterone (DHT), the latter of which is more androgenic and can cause hair loss in the genetically susceptible. A couple of preliminary studies suggests supplementation with saw palmetto can promote hair regrowth, though more research is needed before strong conclusions can be made.

Saw Palmetto's effects on DHT production have also led to saw palmetto being used for benign prostatic hyperplasia (BPH) and lower urinary tract symptoms in men. Some studies have shown positive results, but larger and more well-designed studies have brought its efficacy into question.

What else is Saw Palmetto known as?
Note that Saw Palmetto is also known as:
  • Serenoa Repens
Dosage information

While the active compound(s) are not yet known, it is known that they exist in what is known as the "liposterolic" fraction of the fruits. If using saw palmetto, choose a product that discloses the percentage of the supplement which is this fraction.

Supplementation of saw palmetto tends to be in the range of 160-320 mg, taken once daily, of a product which is 80-90% liposterolic compounds by weight. While it is not confirmed if saw palmetto needs to be taken with food due to the fat soluble nature of this fraction, it is advised.

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