Saw palmettos are palm trees native to the southeastern United States from South Carolina to Florida. In the late 19th and early 20th century, people used saw palmetto berries to promote prostate and urinary tract health.
Saw palmetto trees grow berries that contain health-promoting compounds. These include fatty acids, plant sterols, flavonoids, and polysaccharides. Extracts taken from saw palmetto berries are included in health supplements for men and women.
Saw palmetto’s plant sterols interact with sex hormones, particularly testosterone and estrogen. Research indicates saw palmetto acts as a 5-alpha-reductase inhibitor. This means it stops testosterone from converting to dihydrotestosterone, or DHT. Too much DHT causes enlarged prostate and also male pattern baldness. Saw palmetto also appears to decrease estrogen.
Men take saw palmetto to treat enlarged prostate symptoms. These symptoms include need for nighttime urination and difficulty releasing urine. Saw palmetto does not shrink the prostate gland but instead shrinks prostate lining, relieving pressure in the urethra. The urethra runs through the prostate gland, so an enlarged prostate gland often makes urinating more difficult.
Numerous studies have examined saw palmetto’s effects on enlarged prostate. While some studies found it had no effect, most evidence suggests saw palmetto works better than a placebo at improving enlarged prostate symptoms.
In one study, men taking 320 mg saw palmetto extract had a 50% faster urine flow rate and took 45% fewer nighttime trips to the bathroom. Those in the placebo group had only a 5% improvement in flow rate and a 15% drop in nighttime urination.
A more recent systematic review compared saw palmetto and several other plant-derived compounds as enlarged prostate treatments. These researchers concluded saw palmetto was the most effective at relieving symptoms of enlarged prostate.
An enlarged prostate commonly causes problems producing an erection. According to research, saw palmetto decreases erection problems better than one commonly proscribed enlarged prostate medication.
A 2012 study tested 320 mg saw palmetto extract as a treatment for sexual dysfunction related to enlarged prostate. After 8 weeks, men’s ability to produce and maintain an erection improved by 64%, with libido rising 54%.
Male pattern baldness is also commonly treated with saw palmetto. Baldness decreased in 60% of saw palmetto treated men with mild to moderate baldness in one study. In another study, saw palmetto induced hair growth in 38% of men.
Men and women take saw palmetto extract to lower estrogen levels or counteract estrogen’s effects.
In a double-blind placebo controlled study, 35 men with prostatic hypertrophy were treated with saw palmetto for nearly 3 months. Subjects experienced a significant decrease in estrogen compared to the placebo group.
People also take saw palmetto to reduce symptoms of infectious illnesses, such as coughs, colds, sore throats, or chronic bronchitis. Saw palmetto has also been used to treat migraine headaches. However, these uses have little to research assessing their efficacy.
There are very few reported side effects from taking saw palmetto. Some experience upset stomach when they use saw palmetto. This can result in nausea, vomiting, constipation, or diarrhea. Taking liposterolic (fat-soluble) saw palmetto extract may minimize risk of these side effects.
Other reported saw palmetto side effects include dizziness and headache.
Rarely, people attribute impotence to taking saw palmetto. However, scientists doubt whether saw palmetto actually caused impotence in these cases because impotence occurred at the same rate in men taking sugar pills.
Men taking saw palmetto sometimes have lower libido, increased difficulty producing an erection, testicular discomfort, or breast tenderness or enlargement. However, saw palmetto trials often produce fewer side effects in the test group than the placebo group.
Due to its anti-estrogenic effects, saw palmetto may decrease effectiveness of birth control pills and anticoagulants.
Consult your doctor or use caution taking saw palmetto if you have medical conditions related to hormone levels, heart, stomach, liver, or lungs.
It’s important to take a fat-soluble saw palmetto extract. This ensures proper absorption, since saw palmetto’s active compounds don’t dissolve in water. Saw palmetto extract with an 80 to 90% liposterolic compound is a highly fat-soluble.
The most common saw palmetto dosage is 320 mg per day. This dose can be taken all at once or in two 160 mg doses. This is the recommended dosage for men taking saw palmetto to relieve symptoms of enlarged prostate. However, medical experts recommend seeing a doctor to rule out prostate cancer before using saw palmetto as an enlarged prostate treatment.
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