- Health A to Z
Catherine Ulbricht, Pharm.D., is a senior attending pharmacist at Massachusetts General Hospital, and an assistant professor at Massachusetts College of Pharmacy, Northeastern University, and the University of Rhode Island. She is a founder of Natural Standard Research Collaboration, which provides high-level complementary and alternative medicine content for health-care institutions. She also is a member of the board of directors of the Integrative Medicine Alliance, and chief editor of the Journal of Herbal Pharmacotherapy.
Question:
Have there been any studies on the effectiveness of saw palmetto for stopping hair loss?
Answer:
Saw palmetto is most often used for prostate health. In Europe, men are often advised to take it for symptoms associated with benign prostatic hyperplasia (benign enlargement of the prostate). Although not considered standard care in the United States, it is the most popular herbal treatment for this condition. Results of studies on saw palmetto's effectiveness for prostate-related symptoms are mixed. The most recent study of saw palmetto, published in the February 9, 2006 issue of the New England Journal of Medicine, showed that it was no more beneficial than a placebo (sugar pill).
Biologically, saw palmetto does appear to have some inhibitory action to prevent conversion of testosterone to dihydrotestosterone, a form of the male hormone that is more active in certain tissues.
It has been suggested that saw palmetto may block some effects of testosterone and therefore reduce male pattern hair loss when used topically, similar to the medication finasteride (Propecia®). More studies are necessary before saw palmetto can be recommended for this use.
Saw palmetto may be unsafe when taken by mouth in patients with bleeding disorders, in those taking medications or herbs/supplements that may increase the risk of bleeding, or prior to some surgical/dental procedures. It may also be unsafe during pregnancy and breastfeeding.