It is the measure of how how quickly a food raises the blood sugar.
For many people the glycemic index is a new tool, but it is important and practical way to classify carbohydrate rich foods.
Glycemic index is very easy to understand. It is simply a measure of how quickly a food raises the blood sugar level. The standard is glucose itself, which is assigned the maximum score of 100. Plain glucose would be the worst choice of carbohydrate. Foods that score below 100 raise the blood sugar more slowly than glucose.
The lower the number, the slower it raises blood sugar. And slower generally means healthier and better choice of carbohydrates.
Recent researches suggest that the glycemic index of foods may also play an important role in determining the level of HDL (“good”) cholesterol.
From Harvard medical school guide to men’s health:
Doctors in London investigated 1,420 British adults, studying the glycemic index of their diets as well as their dietary fiber, fat and alcohol consumption and tobacco use. The dietary evaluation was meticulous, requiring all participants to weigh and measure all the food and drink they consumed for seven-day period. The researchers visited all the volunteers in their home, where they measured the heights, weights, and blood pressure and obtained blood samples to determine LDL and HDL cholesterol levels.
As expected, the participants who ate the least total fat, saturated fat, and cholesterol had the lowest LDL (“bad”) cholesterol levels. But although a low-fat diet had the expected favorable impact on the LDL, it did not help the HDL (“good”) cholesterol. On the contrary, the people who ate the least fat had the lowest HDLs. Smoking, alcohol and obesity did not account for the lower-than-expected HDLs. Instead, the glycemic index explained the results, a high glycemic index was associated with a low HDL cholesterol level.
Here are some selected foods and their glycemic index:
Least desirable – high glycemic index foods (70 and above): White bread-95, puffed rice cereals -90, instant mashed potatoes-86, white rice-72, honey-91, jelly beans-80.
Intermediate – moderate glycemic index foods (56-69): Rye bread-65, new potatoes-58, brown rice-66, refined sugar-65, oatmeal cookies-57, pineapple-66, banana-61.
Most desirable – low glycemic index (55 and below): Pumpernickel bread-41, heavy mixed grain bread-30-45, oatmeal-53, fructose-22, yogurt-33, orange-43, apple-36, strawberries-32, peach-28, lentils-28, barley-22, pasta-38, baked beans-43, kidney beans-33.