Alternative Health Blog

Soy foods have been praised and vilified by health researchers over the past decade. There is a significant number of practitioners who contend soy foods, particularly if you stick mostly to whole foods such as edamame (shelled pods), tofu, tempeh and miso, can be formidable protectors against heart disease and cancer.

In contrast, some health advisers warn that soy foods—especially processed soy products and/or isolated soy protein powders and supplements—can result in adverse outcomes if consumed in larger quantities. The hypothesis here is that soy isoflavones when concentrated can go into a sort of overdrive mode in your body.

Keeping the two perspectives in mind, consider a new study by Hong Kong researchers showing a positive association between isoflavones and stroke prevention. If you have stroke (sometimes called a “brain attack”) in your family history, you will be wise to know that soybeans, chickpeas, legumes and clovers are high in isoflavones that can improve artery function.

The most critical arteries are those that run from the heart through the neck and to the brain. Doctors call them the carotid arteries and keeping them clear is a prime strategy for brain health. The study, published online in the European Heart Journal, is pioneering research that used the main artery or brachial artery located in the arm for observational purposes. Blood flow was monitored by using ultrasound. It is likely future studies in the area will directly screen the carotid arteries.

Fifty volunteers took an isoflavone supplement of 80 milligrams per day for 12 weeks, while another 52 subjects consumed a placebo. Increased blood flow in the brachial artery was statistically undeniable—and more dramatic because 80 percent of all participants began the study with compromised blood flow. The Hong Kong suggested the preliminary findings indicate isoflavones could well become a complementary therapy “on top of conventional treatments,” but cautioned more studies were needed.

Eighty percent of the patients began the experiment with an impaired blood flow, but after 12 weeks, there was an improvement in the arteries of the isoflavone-treated patients compared with those on placebos.

For now, it is logical to not self-diagnose and self-treat with isoflavones. But getting more isoflavone foods into your diet—hummus, anyone?—is a healthy idea.

"A balanced diet is still the top priority in promoting health,” wrote the researchers in discussing the hopeful findings that still need scientific vetting. “Diets with higher soy content might be beneficial due to the isoflavone contents. These food products also, in general, have higher contents of polyunsaturated fats, fiber, vitamins and less saturated fat.”

Bob Condor blogs for Alternative Health Journal every Monday, Tuesday, Thursday, Friday and Saturday.