Saw palmetto is the most popular herbal hair loss treatment, although it does not have the approval of the U.S. Food and Drug Administration or large-scale scientific studies to back its use for hair loss. Its popularity among hair-loss sufferers rests in its supposed similarities to finasteride as a treatment for enlarged prostates. Proscar, which is a 5 mg finasteride tablet, is used to treat enlarged prostates, while Propecia, which is 1 mg of finasteride, is used to treat hair loss.
FDA Approved Treatments
As of 2011, minoxidil and finasteride were the only two hair-loss treatments approved by the FDA. Many over-the-counter hair-loss treatments, such as Provillus, include minoxidil packaged with other treatments in order to claim FDA approval, although the only approved item in the package is minoxidil. The lack of an FDA approval does not mean saw palmetto will not work as a hair-loss treatment, only that it has not been shown to work in clinical settings. It is unlikely saw palmetto will ever receive FDA approval, as it is not patented and it typically costs millions of dollars to conduct the tests the FDA requires.
While saw palmetto has not undergone the rigorous tests required for FDA approval, there have been smaller-scale studies done on its effectiveness to treat hair loss. One study, which appeared in the August 2002 Journal of Alternative and Complementary Medicine, indicated that 60 percent of those who took a combination of 400 mg of saw palmetto and 100 mg of beta-sitosterol showed more hair growth than those taking a placebo. The study is not without its problems. The sample size of 19 test subjects is too small and the addition of another drug, beta-sitosterol, makes it difficult to determine if any improvement in hair growth is due to the saw palmetto or the beta-sitosterol.
Saw palmetto has been well tested as a treatment for benign prostatic hypertrophy and there is sufficient evidence of its use as a prostate treatment. The Mayo Clinic gives saw palmetto an "A" rating for prostate issues, which means there is "strong scientific evidence for this use." The two approved uses for finasteride are to treat enlarged prostates and hair loss. The assumption is if saw palmetto works as a prostate treatment it should also work as a hair loss treatment, but this has not been proven sufficiently and the Mayo Clinic gives saw palmetto a "C" rating as a hair loss treatment, stating there is "unclear scientific evidence for this use."
As saw palmetto is not an approved hair-loss treatment any estimate on the proper dosage to treat hair loss is conjecture. Those taking saw palmetto for prostate issues will typically take 320 mg of saw palmetto extract per day. Even though saw palmetto is considered a natural supplement, it does have some potential side effects. According to the Mayo Clinic, the most common side effects including nausea, vomiting, constipation or diarrhea. It is advised you speak to your doctor before beginning any new treatment.