Serenoa rapens - Saw Palmetto

Description

Native to the eastern seaboard of North America from S Carolina, south to Florida, Saw Palmetto is a small palm tree, 2 - 3 m tall. The berries are deep red-brown - black, wrinkled, oblong, 1 - 2.5 cm long, and 1 cm in diameter.

Part Used

Berries.

Constituents

The most active components are represented by a large, complex group of volatile and fatty oils, which includes beta-sitosterol, and short chain fatty acids (e.g. caproic, capric, caprylic, lauric, palmitic, and oleic acids); diterpenes (geranylgeraniol, phytol); triterpenes (cycloartenol, lupeol); sesquiterpene (farnesol); alcohols ( di-, tri-, tetra-, hexa- octa-cosanol). Additional acids, such as caffeic and chlorogenic acids, as well as tannins, sugar and polysaccharides are found in saw palmetto.(1-4)

Mode of Action

This herb has been successfully studied for the treatment of prostatitis and benign prostatic hyperplasia (BPH). As a male ages, more male hormones such as testosterone collect in the prostate. This testosterone in turn converts into a more potent form — dihydrotestosterone (DHT). DHT causes cell multiplication that eventually produces enlargement of the prostate. Left untreated, a certain percentage of cases will lead to prostate cancer. The lipid compounds of saw palmetto have been shown to prevent the conversion of testosterone into DHT and inhibit male hormone binding to cellular and nuclear receptor sites. Saw palmetto also increases the breakdown of DHT already present in the body. In addition to the anti-androgenic action, saw palmetto berries also have anti-inflammatory and anti-edematous activity. Saw palmetto acts by inhibiting cyclooxygenase and 5-lipoxygenase pathways that produce prostaglandin E2 and leukotrienes, and by inhibition of arachidonic acid cascades. The exact constituent responsible is unknown, but is part of the lipid group. Saw palmetto has had a long history of being used on cancer, especially of the urogenital system. This has not been clinically studied to date, but beta-sitosterol although been shown to have anti-cancer activities.(5,6)

There have been many clinical trials, using different protocols (including double-blind and controls) with groups of more than 2,000 BPH patients in Germany. Confirmation in multiple studies has confirmed reduction in prostate size within 30 days. It should be noted that almost all authorities feel the use of alcohol extract or straight berries far exceeds the effectiveness of the water extractions.

Saw palmetto s polysaccharides have also been shown to have immune-stimulating properties. This herb also has anti-androgen and anti-edema effects. Beta-sitosterol might be responsible for claims that saw palmetto is able to enlarge breast size in pubescent women since studies on mice indicate that beta-sitosterol has an estrogenic activity. Saw palmetto has bee shown to reduce female hirsutism (excessive male pattern hair growth).(7) There have also been claims for saw palmetto`s nutritive, tonic, diuretic, sedative and antiphlogistic effects.(8) It has been used specifically for head colds. An extract of S. repens was shown to possess anti-allergic and anti-inflammatory activity in rats, mice and guinnea pigs. This might be due to its ability to inhibit both cyclooxygenase and 5-lipoxygenase, which are associated with inflammation.(9)

Therapeutic action

Anti-BPH, tonic, aphrodisiac, nutritive, diuretic, sedative, antiphlogistic.

Energetics

Other

Saw palmetto is described as a bit sweet, oily, astringent, pungent, warm, dry, with secondary qualities of restoring and stimulating. It enters the Kidney, Spleen, Chong and Ren meridians and has an impact on reproduction, urinary organs, nerves and thyroid with an air tropism.(10) Tierra lists saw palmetto as pungent, sweet and warm, affecting the Kidney, Spleen and Liver meridians.(11)

Folklore

This plant was used by white and black cultures in the southern U.S. as a nutrient to increase growth in humans and livestock. The Eclectics used it to increase nutrient assimilation and to promote weight gain. They also used it to restore and relax the nervous system, to restore reproduction and the respiratory mucosa. It has been used to ‘tone` the thyroid.

Dosage

dried herb - 1 - 2 g.
tincture (90%) - 15 -20 drops three times daily
extract (solid) - 160 mg, twice daily

Toxicity and Contraindications

From the many clinical studies that have been done, no toxicity or side effects have been found. The U.S. Food and Drug Administration has put saw palmetto on a list of ``Herbs of Undefined Safety``.

Official Recognition and Medical References

Belgium - Approved for BPH
Germany - Commision E p 201
PDR for Herbal Medicine - p. 1136
Sweden - Classified as Nat product
UK - General Sales
US - Dietary supplement

References

1. Duke, J.A. CRC Handbook of Medicinal Herbs, CRC Press, Boca Raton, FL, 1985, p. 443.
2. Murray, M., Saw Plametto, Natures answer to enlarged prostate, Health Counselor; Impakt Com. 1998.
3. Tyler, V.E., Herbs of Choice, Pharmaceutical Products Press, New York, NY, 1994, p. 82.
4. Snow, J; Monograph: Serenoa repens bartram (Palmae); The Protocol J. of Bot. Med; Winter 1996, p. 15-16
5. Duke, J.A., Ibid.
6. Tyler, V.E.,Ibid.
7. Snow, Iibid.
8. Duke, J.A. Ibid.
9. Lawrence review of Natural Product; Saw Palmetto; Mar. 1994
10. Holmes, P., The Energetics of Western Herbs (2 volumes), Artemis Press, Boulder, CO, 1989, p. 294.
11. Tierra, M., Planetary Herbology, Lotus Press, Sante Fe, NM, 1988, p. 305.