The glycemic index was developed between 1980-1991 at the University of Toronto by Dr David Jenkins and colleagues. They were researching different foods to determine which foods could benefit people with diabetes.
Diabetes (formerly known as diabetes mellitus) is a condition in which the body is not able to use blood sugar as energy, due either to having too little insulin or being unable to use available insulin.
It was found that low GI foods could be of benefit to diabetics (diabetics are people who suffer from diabetes).
The slow digestion and absorption of low GI foods and subsequent gradual rises in blood sugar and insulin levels helped improve the lipid* and blood glucose levels in people with both type 1 and type 2 diabetes.
*lipids are fatty substances which can be found in the blood.
Type 1 diabetes is a condition in which the pancreas makes little or no insulin.
Type 2 diabetes is a condition in which the pancreas does not make enough insulin or is unable to effectively use the insulin it makes to convert blood glucose to energy. Less severe than type 1 diabetes, type 2 diabetes can be controlled through weight loss, medications (which may include insulin injections), exercise and diet.
Low GI foods in a diabetics diet are generally encouraged as they help control blood glucose levels. However, high GI foods can also be of benefit to diabetics (and others) with hypoglycemia.
Hypoglycemia refers to a state in which there is an abnormally low level of glucose in the blood. By consuming high GI foods, people with hypoglycemia can quickly restore their blood glucose levels.
High GI foods can also be of benefit to people who have undertaken endurance exercise and wish to restore energy levels.
Whilst initial research focused on helping diabetics, low GI foods can be of benefit to everybody.