TTUHSC School of Medicine
HomeWest Texas Cancer Survivors NetworkAsk the Expert

Cancer Nutrition Network for Texans

Saw Palmetto

CNNT Logo

What is it?

Saw Palmetto is a bushy palm with a maximum height of 6 feet that is common in the southern United States (South Carolina to Florida to southern California). The part of the plant that appears to have medicinal properties is the fruit. The fruit is a berry approximately 1 inch long that varies in color from deep purple to black. The partially dried to dried fruit is used to make a variety of commercially available products. Most of these products include “Saw Palmetto” in the name. The mode of administration is usually in capsule form with the dosage ranging from 80-1,000 mg per capsule. The products are usually used by men with symptoms ranging from prostate complaints to irritable bladder.

How does it work?

Compounds identified in the extracts include plant sterols, flavonoids, water-soluble polysaccharides, and free fatty acids. Most of the studies have concentrated on the anti-androgenic and anti-estrogenic effects of the plant sterols. Studies suggest that these chemicals inhibit the binding of dihydrotestosterone (DHT), a male sex hormone, to receptors in the prostate. This action appears to block the accumulation of DHT in the prostate possibly helping to prevent prostate hyperplasia or enlargement.

Is it effective?

Maybe. Several clinical trials of short duration have already been done with Saw Palmetto extracts. Stomach complaints following intake was the only problem that was observed in some individuals. No health hazards were reported. In each of the clinical trials the extract appeared to increase peak urinary flow and alleviate voiding problems. No direct effects on prostate volume or size were found. In one of the studies, the treatment was also found to have no effect on serum PSA levels.

What is the state of the science?

Additional clinical trials with Saw Palmetto extracts are needed to more accurately understand the potential of this herbal remedy for urinary tract disorders. Patients with hormone-dependent cancers should consult with their physician before they consider the use of Saw Palmetto extracts. The anti- estrogenic and anti-androgenic effects could complicate conventional therapies. In addition, the use of these extracts by women who are pregnant or breast-feeding is not recommended. One additional word of warning, urinary tract problems can be a symptom of a more serious problem (cancer of the bladder or prostate). Relieving the symptom without understanding the cause could delay effective treatment of the underlying problem.


Edward G. Miller, Ph.D., Professor, Department of Biomedical Sciences for Baylor College of Dentistry.

Back to Ask the Expert

©