The glycemic index, glycaemic index, or GI is a measure of the effects of carbohydrates in food on blood sugar levels. It estimates how much each gram of available carbohydrate (total carbohydrate minus fiber) in a food raises a person’s blood glucose level following consumption of the food, relative to consumption of glucose. Glucose has a glycemic index of 100, by definition, and other foods have a lower glycemic index.
Glycemic index is defined for each type of food, independent of the amount of food consumed. Glycemic load accounts for the amount of food consumed and is calculated in terms of glycemic index.
GI values can be interpreted intuitively as percentages on an absolute scale and are commonly interpreted as follows:
Low GI (55 or less): most fruits and vegetables; legumes; some whole, intact grains; nuts; tagatose; fructose; kidney beans; beets; chickpeas
Medium GI (56–69): whole wheat products, pita bread, basmati rice, grapes, sucrose, raisins, pumpernickel bread, cranberry juice, regular ice cream
High GI (70 and above): white bread, most white rices, corn flakes, extruded breakfast cereals, glucose, maltose, maltodextrins, white potato, pretzels
A low-GI food will release glucose more slowly and steadily, which leads to more suitable postprandial (after meal) blood glucose readings. A high-GI food causes a more rapid rise in blood glucose levels and is suitable for energy recovery after exercise or for a person experiencing hypoglycemia.
Several lines of recent  scientific evidence have shown that individuals who followed a low-GI diet over many years were at a significantly lower risk for developing both type 2 diabetes, coronary heart disease, and age-related macular degeneration than others.
A study from the University of Sydney in Australia suggests that having a breakfast of white bread and sugar-rich cereals, over time, may make a person susceptible to diabetes, heart disease, and even cancer.
A study published in the American Journal of Clinical Nutrition found that age-related adult macular degeneration (AMD), which leads to blindness, is 42 percent higher among people with a high-GI diet, and concluded that eating a lower-GI diet would eliminate 20 percent of AMD cases.
Recent animal research provides compelling evidence that high-GI carbohydrate is associated with increased risk of obesity. In humans, a recent study proves that low-glycemic index diets work better than low-fat or Atkins diets.
Also, a ‘low carbohydrate-high protein’ diet will increase the incidence of cardiovascular diseases, as shown in an article published in British Medical Journal.
Here (Eat Informed – Glycemic Index) you can find details about our implementation of a tool to handle this database.
We are now trying to collect data for the glycemic index database. We need facts and we need links to organizations studying it or doing research on the subject.
If you have such information, please add comments in this page with the relevant links.
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