Harvard’s Dr. Frank Hu in 2007 called for a paradigm shift in dietary prevention of heart disease, de-emphasizing the original diet-heart hypothesis and noting instead that “. . . reducing dietary GL [glycemic load] should be made a top public health priority.” Jim Mann at the University of Otago (Dunedin, New Zealand) authored a 2007 review of carbohydrates and effects on heart disease and diabetes. Here are highlights from the article summary in the European Journal of Clinical Nutrition:
The nature of carbohydrate is of considerable importance when recommending diets intended to reduce the risk of type II diabetes and cardiovascular disease and in the treatment of patients who already have established diseases. Intact fruits, vegetables, legumes and whole grains are the most appropriate sources of carbohydrate. Most are rich in [fiber] and other potentially cardioprotective components. Many of these foods, especially those that are high in dietary fibre, will reduce total and low-density lipoprotein cholesterol and help to improve glycaemic control in those with diabetes.
Frequent consumption of low glycaemic index foods has been reported to confer similar benefits, but it is not clear whether such benefits are independent of the dietary fibre content of these foods or the fact that low glycaemic index foods tend to have intact plant cell walls.
A wide range of carbohydrate intake is acceptable, provided the nature of carbohydrate is appropriate. Failure to emphasize the need for carbohydrate to be derived principally from whole grain cereals, fruits, vegetables and legumes may result in increased lipoprotein-mediated risk of cardiovascular disease, especially in overweight and obese individuals who are insulin resistant.
Why does this matter to me and readers of this blog? Dietary carbohydrates are a major determinant of blood sugar levels, tending to elevate them. Chronically high blood sugar levels are associated with increased complication rates from diabetes. People with diabetes are prone to develop heart disease, namely coronary artery disease, which causes heart attacks, weakness of the heart muscle, and premature death.
Mann, J. Dietary carbohydrate: relationship to cardiovascular disease and disorders of carbohydrate metabolism. European Journal of Clinical Nutrition, 61 (2007): Supplement 1: S100-11.
Hu, Frank. Diet and cardiovascular disease prevention: The need for a paradigm shift. Journal of the American College of Cardiology, 50 (2007): 22-24.