Eating soy nuts improves endothelial function in postmenopausal women

Eating soy nuts instead of red meat decreases some markers of inflammation and improves endothelial function in postmenopausal women with a collection of cardiometabolic risk factors, a new study by researchers at Isfahan University of Medical Sciences in Iran and the Harvard School of Public Health found. In previous studies by the same group, subjects who ate soy nuts also showed improvements in their lipid profiles, suggesting that soy may improve cardiac health among a subgroup of women.

Previous research has looked at the effect of soy on inflammatory markers and endothelial function in the general population, but this was the first study to look more narrowly at how eating soy nuts (versus soy protein) would specifically affect postmenopausal women who already had a number of metabolic abnormalities. Consuming soy protein did not produce the same benefits, the researchers found.

Women (and men) who have certain cardiometabolic risk factors (abdominal obesity, high blood pressure, high cholesterol and insulin resistance) are at high risk for type 2 diabetes and for heart disease, the number one killer of people with diabetes. Studies have shown that lifestyle changes, such as losing moderate amounts of weight and increasing physical activity, can substantially reduce the chances of developing diabetes for people who already have these risk factors.

"A well-balanced meal plan should be part of any program designed to lose weight or improve overall health. This study shows that adding soy nuts to your diet - and eating less red meat - could be an important part of that meal plan," said lead researcher Dr. Leila Azadbakht, at the Isfahan University of Medical Sciences Department of Nutrition in Iran.

Soy is also often used as an alternative or adjunct to hormone replacement therapy in postmenopausal women. The researchers note that the mechanisms by which soy affects the inflammatory state may be related to the effects of soy phytoestrogens, which mimic hormone replacement therapy. However, more research needs to be done to understand the mechanisms through which soy affects inflammation and endothelial function. It is also unclear whether other groups of postmenopausal women would benefit as much as those participating in this study who had a number of high risk factors for diabetes and heart disease.