Last week in my blog I reviewed the diagnostic criteria for metabolic syndrome. In that blog I also reminded you that people who have metabolic syndrome have developed dysfunction in the chemical processes in their body that are necessary for the maintenance of their health and their life. These imbalances are causing many of the chronic diseases of our day: arthritis, diabetes, high blood pressure, high cholesterol, heart disease, and cancer. Metabolic syndrome is predominantly caused by obesity and insulin resistance which occur as a result of eating a diet to high in glucose or to many foods with a high glycemic index.
The glycemic index is a measure of how much each gram of available carbohydrate in a food raises a person’s blood glucose level. Glucose has a glycemic index of 100 so all other foods are compared to this. Foods with carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream have a high glycemic index; whereas, foods with carbohydrates that break down more slowly, releasing glucose more gradually into the bloodstream have a low glycemic index. The concept was developed by Dr. David Jenkins and colleagues in 1980-1981 at the University of Toronto in their research to find out which foods were best suited for people with diabetes. Foods with a low glycemic index (55 or less) do not cause as high a spike in blood stream glucose and therefore do not require as much insulin to metabolize that glucose; while foods with a high glycemic index require much more insulin to metabolize the sugar or glucose load.
Examples of high glycemic index foods include: white bread, most white rices, corn flakes, or breakfast cereals and have a glycemic index of 70 and above. Some examples of low glycemic index foods include: most fruits and vegetables, legumes, nuts, chick peas, beets and have a glycemic index of 55 or less. A low glycemic index food will release sugar more slowly and steadily, which leads to more suitable after meal blood glucose readings.
Over the years postprandial or after meals high blood sugar (hyperglycemia) has been considered a risk factor for the development of diabetes; but more recent evidence shows that it is also a risk for heart disease and kidney disease in the non-diabetic population. A study from the University of Australia also showed that having a breakfast of white bread and sugar-rich cereals, over time, made a person more susceptible to diabetes, heart disease and even cancer.
There are areas in the world where people eat high glycemic index foods such as potatoes and rice, but without a high level of obesity or diabetes. In these areas of the world, such as Asia and South America, beans and fresh fruits and vegetables are also eaten at such a high amount that the overall glycemic effect is lowered. The balance of high and low glycemic index foods produces a moderate glycemic index effect. And, if you add protein or good fats (unsaturated or saturated fats) this will also lower a meals overall glycemic load.