Saw Palmetto Benefits & Side Effects

Saw palmetto supplements are made from extract from the berries of the saw palmetto tree. You can buy it in health food stores in a variety of forms, ranging from teas to capsules and liquids. Saw palmetto is one of the most frequently purchased herbal supplements and it has been used for many different ailments, including prostate and urinary issues.

Effects

Saw palmetto extract affects sex hormone function in both men and women. In men, saw palmetto has anti-androgen activity, which means that it interferes with the signaling of testosterone and one of its related forms, dihydrotestosterone. In women, saw palmetto promotes estrogen effects while blocking progesterone effects.

Benefits for Men

Saw palmetto is commonly used to treat lower urinary tract symptoms and benign prostatic hypertrophy, or enlarged prostate, in men. Early studies suggested that saw palmetto improved urine flow and discomfort, but a 2009 review of clinical trials, published in the "Cochrane Database System Review," reports that saw palmetto is not more effective than placebo in reducing scores on a general urinary symptom assessment including these symptoms. There was also no significant reduction in prostate size. However, there is evidence that it may be effective in reducing the number and frequency of urinations.

Benefits for Women

Because saw palmetto reduces the function of testosterone and promotes estrogen function, it can help reduce unwanted hair growth in polycystic ovarian syndrome. It may also increase breast size and reduce menstrual problems because of the hormonal effects. However, more scientific studies are needed to fully demonstrate these effects.

Other Benefits

Saw palmetto may also have anti-inflammatory and anti-proliferative effects, which could make it beneficial for preventing cancer. It may also increase immune system function. However, more studies are needed to fully evaluate these uses.

Side Effects

Because of the anti-sex hormone effects of saw palmetto, sexual dysfunction is a common side effect. Fatigue and headaches may also occur. Saw palmetto may interact with drugs that affect sex hormones or have anti-inflammatory actions.