Consuming soy protein in place of other proteins may lower levels of LDL (“bad”) cholesterol to a small extent.

Soy isoflavone supplements may help to reduce the frequency and severity of menopausal hot flashes, but the effect may be small.

It’s uncertain whether supplements can relieve cognitive problems associated with menopause.

Current evidence suggests that soy isoflavone mixtures do not slow bone loss in Western women during or after menopause.

Diets containing this protein may slightly reduce blood pressure.

There’s not enough scientific evidence to determine whether supplements are effective for any other health uses.

Current National Center for Complementary and Integrative Health (NCCIH)-funded studies are investigating a variety of topics, including stroke outcomes, anti-inflammatory effects, and effects on diabetes.

Side Effects Of Soy

Except for people with allergies, soy is believed to be safe when consumed in normal dietary amounts. However, the safety of long-term use of high doses of extracts has not been established.

The most common side effects are digestive upsets, such as stomach pain and diarrhea.

Long-term use of soy isoflavone supplements might increase the risk of endometrial hyperplasia (a thickening of the lining of the uterus that may lead to cancer). Soy foods do not appear to increase the risk of endometrial hyperplasia.

Current evidence indicates that it’s safe for women who have had breast cancer or who are at risk for breast cancer to eat soy foods. However, it’s uncertain whether soy isoflavone supplements are safe for these women. 


Tell all your health care providers about any complementary or integrative health approaches you use. Give them a full picture of what you do to manage your health. This will help ensure coordinated and safe care.


All information has been provided courtesy of MedLinePlus from the National Library of Medicine and from the FDA.