Saw palmetto

Saw palmetto (Serenoa repens) is a small palm tree native to the eastern United States. Its fruit is used as a traditional or folk remedy for urinary symptoms associated with an enlarged prostate gland, as well as for chronic pelvic pain, bladder disorders, decreased sex drive, hair loss, hormone imbalances, and prostate cancer.

Several small studies suggest that Saw palmetto may be effective for treating BPH (benign prostatic hyperplasia) symptoms. Saw palmetto is used by over 2 million men in the United States for the treatment of benign prostatic hyperplasia and is commonly recommended as an alternative to drugs approved by the Food and Drug Administration. The herb is widely used in Europe, where half of German urologists prefer prescribing plant-based extracts to synthetic drugs.

In 2010 two Italian studies carried out on patients with BPH treated with extract of Serenoa repens. The studies were carried out on a total of 70 adult patients with diagnosis of benign prostatic hypertrophy. In one study the patients were treated with Serenoa repens 320 mg/day for 30 days; in the other study the patients received Serenoa repens 320 mg/day or Pygeum africanum (Tadenan) 4 capsules of 25 mg/day for 30 days.Both studies showed an improvement also in terms of reduction of the micturition rate and of prostate size. Saw palmetto improved the ability to urinate by allowing urine to flow out of the bladder faster. Also the tolerability profile was favorable.

In a 2011 study Saw Palmetto was well tolerated, but was no better than placebo in improving urinary symptom scores. Another 2011 study found that the combination of Serenoa repens, selenium and lycopene is more effective than Serenoa repens alone to prevent hormone dependent prostatic growth. Lycopene-Se-Serenoa repens was more effective than Serenoa repens alone for decreasing prostate weight.

 In vitro studies have found that Saw palmetto inhibits growth of prostatic cancer cells and may induce apoptosis. 

Androgenetic alopecia (AGA) is characterized by the structural miniaturization of androgen-sensitive hair follicles in susceptible individuals. Biochemically, one contributing factor of this disorder is the conversion of testosterone (T) to dihydrotestosterone (DHT) via the enzyme 5-alpha reductase (5AR) This metabolism is also key to the onset and progression of benign prostatic hyperplasia (BPH). A 2006 study establishes the effectiveness of naturally occurring 5AR inhibitors against AGA. The extract of Saw Palmetto inhibits the activity of 5-alpha reductase enzyme.

Saw Palmetto is available as liquid extracts, tablets, capsules, and as an infusion or a tea. Products that have a fat-soluble extract of the saw palmetto berry are better choices, because the active compound does not dissolve well in water. So drinking a tea or water extract is not likely to have an effect on the symptoms of BPH.

Possible side effects:

Saw palmetto appears to be well tolerated by most users. It may cause mild side effects, including stomach discomfort.

Source: 1. NCCAM, 2. Cochrane Database Syst Rev. 2009 Apr 15;(2):CD001423., 3. N Engl J Med. 2006 Feb 9;354(6):557-66., 4. J Urol. 2011 Oct;186(4):1524-9. Epub 2011 Aug 19., 5. Minerva Urol Nefrol. 2010 Dec;62(4):335-40., 6. Nutr Cancer. 2006;55(1):21-7., Scott Zona