Saw palmetto

Saw palmetto
Saw palmetto

Saw palmetto is an extract derived from the deep purple berries of the saw palmetto fan palm (Serenoa repens), a plant indigenous to the coastal regions of the southern United States and southern California.

There is an estimated one million acres of wild saw palmetto palms in Florida, where the bulk of commercial saw palmetto is grown.

General use

Saw palmetto is used by natural health practitioners to treat a variety of ailments in men and women, such as testicular inflammation, urinary tract inflammation, coughs, and respiratory congestion.

It is also used to strengthen the thyroid gland, balance the metabolism, stimulate appetite, and aid digestion. Most of the evidence supporting these uses is anecdotal and has not been proven by controlled clinical trials.

However, there is much scientific documentation outlining the effectiveness of the herb in treating irritable bladder and urinary problems in men with benign prostate hyperplasia (BPH), an enlargement of the prostatic gland. BPH produces a swelling of the prostate gland that obstructs the urethra.

This causes painful urination, reduced urine flow, difficulty starting or stopping the flow, dribbling after urination, and more frequent nighttime urination. Saw palmetto does not reduce prostate enlargement. Instead, it is thought to work in a variety of ways. First, it inhibits the conversion of testosterone into dihydrotestosterone (DHT).

BPH is thought to be caused by an increase in the ratio of testosterone to DHT. Secondly, saw palmetto is believed to interfere with the production of estrogen and progesterone, hormones associated with DHT production.

In addition to causing pain and embarrassment, BPH can lead to serious kidney problems if undiagnosed and left untreated. It is a common problem in men over the age of 40. Estimates are that 50-60% of all men will develop BPH in their lifetimes.

The Agency for Health Care Policy and Research estimates there are six million men between the ages of 50-79 who have BPH serious enough to require some type of therapy. Yet only half of them seek treatment from physicians.

Health practitioners in both the allopathic and natural medicine communities recommend annual prostate for men over the age of 50, and an annual blood test that measures prostate-specific antigen (PSA), a marker for prostate cancer.

Recently, a number of clinical trials have confirmed the effectiveness of saw palmetto in treating BPH. Many of these trials have shown saw palmetto works better than the most commonly used prescription drug, finasteride, sold unter the trade name Proscar.

Saw palmetto with their berry fruit
Saw palmetto with their berry fruit

Saw palmetto is effective in nearly 90% of patients after six weeks of use, while Proscar is effective in less than 50% of patients. In addition, Proscar may take up to six months to achieve its full effect. Since Proscar blocks the production of testosterone, it can cause impotence and breast enlargement. Also, saw palmetto is significantly less expensive than Proscar.

A one-month supply of saw palmetto costs $12-25, while a one_month supply of Proscar costs $65-75. Other prescription drugs used to treat BPH are Cardura (doxazosin), Hytrin (terazosin), and Flomax (tamsulosin hydrochloride).

Originally prescribed to treat hypertension, Cardura and Hytrin can cause a drop in blood pressure, causing lightheadedness and fainting. Presently, saw palmetto is being evaluated by the U.S. Food and Drug Administration (FDA) for treatment of BPH.

If approved, it would become the first herbal product to be licensed by the agency as a treatment for a specific condition. Saw palmetto is listed in the Physicians Desk Reference for Herbal Medicine (1998 edition) as a treatment for prostate complaints and irritable bladder.

Since the 1960s, extensive clinical studies of saw palmetto have been done in Europe. A review of 24 European trials appeared in the November 1998 issue of the Journal of the American Medical Association.

The trials involved nearly 3,000 men, some taking saw palmetto, others taking Proscar, and a third group taking a placebo. The men taking saw palmetto had a 28% improvement in urinary tract symptoms, a 24% improvement in peak urine flow, and 43% improvement in overall urine flow.

The results were nearly comparable to the results from the group taking Proscar and superior to the results from men taking the placebo. As of 2002, however, many American physicians still regard the effectiveness of saw palmetto as requiring further proof.

Uses in women

There is very little documentation or scientific research regarding saw palmetto use in women. However, several studies in the 1990s show that the BPH drug Proscar can be effective in stopping unwanted facial and body hair growth, and in treating thinning hair in women.

It works by blocking the action of an enzyme called 5-alpha reductase. Anecdotal reports suggest that saw palmetto may be as effective as Proscar in treating unwanted hair growth and thinning hair, and in preventing some types of acne.

It has also been used to treat urinary tract inflammation and help relieve the symptoms of menstruation. There are claims that it can be used to enlarge breasts, but these claims have not been scientifically tested.


Saw palmetto berries have been used in American folk medicine for several hundred years as an aphrodisiac and for treating prostate problems.

Native Americans in the southeast United States have used saw palmetto since the 1700s to treat male urinary problems. In the 1800s, the medical botanist John Lloyd noted that animals that ate saw palmetto appeared healthier and fatter than other livestock.

Early American settlers noticed the same effects and used the juice from saw palmetto berries to gain weight, to improve general disposition, as a sedative, and to promote reproductive health.

In the United States, the medicinal uses of saw palmetto were first documented in 1879 by Dr. J.B. Read, a physician in Savannah, Georgia, who published a paper on the medicinal benefits of the herb in the April 1879 issue of the American Journal of Pharmacy.

He found the herb useful in treating a wide range of conditions. “By its peculiar soothing power on the mucous membrane it induces sleep, relieves the most troublesome coughs, promotes expectoration, improves digestion, and increases fat, flesh and strength.

Its sedative and diuretic properties are remarkable,” Read wrote. “Considering the great and diversified power of the saw palmetto as a therapeutic agent, it seems strange that it should have so long escaped the notice of the medical profession.”

A pungent tea made from saw palmetto berries was commonly used in the early 1900s to treat prostate enlarge ment and urinary tract infections. It was also used in men to increase sperm production and sex drive, although these uses are discounted today.

One of the first published medical recommendations that saw palmetto was effective in treating prostate problems appeared in the 1926 edition of the United States Dispensatory. In the late 1920s, the use of medicinal plants, including saw palmetto, began to decline in the United States, while at the same time, it was on the rise in Europe.


People taking saw palmetto should use only standardized extracts that contain 85–95% fatty acids and sterols. Dosages vary depending on the type of saw palmetto used.

A typical dose is 320 mg per day of standardized extract, or 1–2 g per day of whole berries that have been dried and ground. It may take up to four weeks of use before beneficial effects are seen.

In late 1999, the web-based independent consumer organization tested 27 leading brands of saw palmetto for fatty acid and sterol content. Ten of the brands contained less than the minimum recommended level of 85% fatty acids and sterols.


There are no special precautions associated with taking saw palmetto, even in high doses. BPH can become a serious problem, however, if left untreated. Men who are experiencing symptoms should be examined by a physician, since the symptoms of BPH are similar to those of prostate cancer.

Men over the age of 50 should have a yearly prostate examination. Saw palmetto should be used only under a doctor’s supervision by people with prostate cancer, breast cancer, or any sex hormone related diseases.

Although the effects of saw palmetto on a fetus is unknown, pregnant women are advised not to take saw palmetto. Saw palmetto can alter hormonal activity that could have an adverse effect on the fetus.

Women taking birth control pills or estrogen replacement products should consult a physician before taking saw palmetto. Persons taking testosterone or other anabolic steroids should not take saw palmetto without first consulting their doctor.

Physicians who accept saw palmetto as an effective remedy for prostate problems nevertheless point out that it is not completely free of side effects.

In rare cases, allergic reactions to saw palmetto have been reported. Symptoms include difficulty breathing, constricting of the throat, hives, and swelling of the lips, tongue, or face. Persons experiencing any of these symptoms should stop taking saw palmetto and seek immediate medical attention.

Side effects

Other reported minor side effects are rare. They include cramps, nausea, diarrhea, and headache.


Saw palmetto may interfere with such hormone-related drugs as testosterone and estrogen replacements, including Premarin, Cenestin, Vivelle, Fempatch, and Climara.

It may also interact with birth control pills, such as Triphasil, Ovral, Lo-Ovral, Nordette, Alesse, Demulen, and Ortho-Novum. Anyone on these types of medications should consult with their doctor before taking saw palmetto. There are no known restrictions on food, beverages, or physical activity while taking saw palmetto.

Several herbs and minerals have been used in conjunction with saw palmetto in treating BPH. A 1996 European study showed positive results in treating patients with a daily dose of 320 mg of saw palmetto extract and 240 mg of nettle root extract.

Many alternative health practitioners also recommend saw palmetto be used in combination with the herb pygeum africanung, pumpkin seeds, zinc, flaxseed oil, certain amino acids, antioxidants, and diets high in protein and soy products.

Some factors that can impair the effectiveness of saw palmetto include beer, cigarette smoke, and some chemical pesticides used on fruit and vegetables. Some physicians recommend using saw palmetto in addition to a prescription medicine, such as Proscar, Hytrin, or Cardura.