Soy Lowers Risk of Heart Disease in Type 2 Diabetics, U of G study finds

September 30, 2009 - News Release

A diet that includes soy protein helps lower cholesterol and reduce the risk of cardiovascular disease in adults diagnosed with Type 2 diabetes, University of Guelph researchers have found.

In a study published in the Journal of Nutrition, the researchers found that soy protein reduces serum LDL – so-called “bad” cholesterol – in adults with Type 2 diabetes who are managing their disease by controlling their diets rather than with medication.

“Everyone who has Type 2 diabetes is at a higher risk for heart disease,” said Alison Duncan, a professor in the Department of Human Health and Nutritional Sciences. “So it is encouraging to show that it is possible to control one of the major risk factors by using soy as a dietary preventative strategy.”

It’s estimated that there are nearly one-quarter of a billion people in the world have diabetes, with more than two million of them in Canada. Up to 90 per cent of diabetes cases are Type 2, which typically develops in adulthood and is often linked to lifestyle factors such as diet. The number of people with Type 2 diabetes is increasing dramatically due to rising rates of obesity, sedentary lifestyles and an aging population. Up to 80 per cent of people with diabetes will die as a result of a heart attack or stroke.

The randomized, double-blind study followed 29 adults with diet-controlled Type 2 diabetes for nearly five months. The participants were given powdered soy protein isolate formulated to replace other high-protein foods such as milk, cheese and meats in their daily diet. They were also asked to avoid other soy foods and natural health products, protein bars, green tea, flaxseed, beans and legumes that contain ingredients that may affect blood cholesterol levels.

Consumption of the soy protein lowered serum LDL cholesterol as well as the ratio of LDL to HDL (“good” cholesterol). It also had a positive effect on proteins in the blood that bind to fat. The soy protein did not affect total cholesterol levels.

Nor did it have any effect on blood sugar, which was disappointing, said Duncan. Those results are reported separately in a paper to be published in the British Journal of Nutrition.

“Still, we were very encouraged by the results of this study because it reinforces the fact that there is a lot we can do in our lifestyle to manage type 2 diabetes,” said Duncan.

This research project was funded by the Heart and Stroke Foundation of Ontario.

For more information, contact Alison Duncan at 519-824-4120, Ext. 53416 or
For media questions, contact Communications and Public Affairs: Lori Bona Hunt, Ext. 53338 or, or Barry Gunn, Ext. 56982 or

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