By Dr Ananya Mandal, MD
Glycemic index has been of great interest to researchers and practicing physicians over recent years as a way of helping people with impaired glucose tolerance or diabetes mellitus plan their diets.
Numerous studies have shown that people who eat a diet with a low glycemic index are at a significantly reduced risk of developing type 2 diabetes and eventually coronary heart disease compared to those who do not.
Low glycemic index foods and diabetes prevention
Foods with a high glycemic index such as white rice or potatoes lead to an immediate surge in the blood sugar level because the glucose is so easily absorbed from the food eaten. This is thought to increase the risk of diseases such as type 2 diabetes and coronary heart disease.
Frequent “spikes” in the blood glucose are thought to promote these conditions by directly raising insulin levels, by increasing glycative stress and by increasing oxidative stress in the blood vessels.
Foods with a low glycemic index release sugar into the bloodstream slowly, therefore preventing sharp increases in glucose and therefore insulin. In the long term, this is thought to prevent insulin resistance, a condition where cells in the body no longer respond properly to the presence of insulin. This can eventually lead to type 2 diabetes.
Low glycemic index foods and coronary heart disease prevention
Previously, high blood sugar levels after a meal have mainly been considered a risk factor among the diabetic population. However, more recent studies have shown that postprandial hyperglycemia may also increase the risk of atherosclerosis in the nondiabetic population.
Reviewed by Sally Robertson, BSc
Last Updated: Jul 20, 2014