Soy Isoflavones & Grape Resveratrol

Soybean, the protein-rich seed of a hairy Asian legume, is a significant source of isoflavones, compounds that exert a hormonal activity similar to the human estrogen. Resveratrol is a natural product found in abundance in grape skins and red wine. It is produced to enhance plant resistance to fungal, bacterial and viral infections. Both soy isoflavones and grape resveratrol can provide health benefits, but you should not take isoflavone, resveratrol or any other supplements without first consulting with your doctor.

Estrogenic and Anti-estrogenic Activity

Due to structural similarities to estrogen, both resveratrol and isoflavones exhibit an estrogen-like action, although it is much weaker with regard to the body's own estrogen. As a result, soy isoflavones and resveratrol could act as estrogen-antagonists, according to Jane Higdon, Ph.D., of the Linus Pauling Institute at Oregon State University. R. Lu and G. Serrero at the University of Maryland School of Pharmacy also demonstrated resveratrol's anti-estrogen property in a study published in the June 1999 edition of the "Journal of Cellular Physiology."

Cancer

Increased exposure of the breast tissue to estrogen is strongly associated with breast cancer. The natural female hormone estrogen stimulates cell proliferation in the milk-bearing glands of the breast, where most breast cancers arise. In vivo, the estrogen antagonist actions of resveratrol inhibit breast cell proliferation and possibly breast cancer, according to Lu and Serrero. Soy isoflavones also can inhibit hormone-induced cancers such as those of the breast, prostate and cervix. Most of these results are based on animal research models. Therefore, you should take resveratrol or isoflavone supplements with care, only under the supervision of your doctor.

Heart Disease and Stroke

Soy isoflavones interact with estrogenic receptors found in the bone and cardiovascular system, thereby acting as estrogen agonists. These estrogenic activities of soy isoflavone reduce low-density lipoprotein and cholesterol levels, which is particularly good for your heart's health, according to Higdon. Damage to blood vessels caused by fatty substances facilitates the formation of blood clot within a blood vessel. The complete blockage of a cerebral artery caused by a blood clot results in a stroke; similarly, a heart attack will result when a blood clot blocks a coronary artery. In cell culture and animal studies, both soy isoflavones and resveratrol inhibited blood clot formation and thus reduced the risk of heart attack and stroke, according to an article published online in January 2006 by the Linus Pauling Institute.

Safety

Be careful about soy foods if you have a known food allergy. Common complications of soy allergy include skin irritation, nausea, digestive ailments, respiratory troubles and low blood pressure. Soy is also not recommended for people with thyroid gland disease. It affects normal thyroid functioning, causing a hypothyroid state. Resveratrol has no prominent side effects in humans, but it should not be used with blood-thinning medications such as warfarin.