What is a glycemic index?
It is better to eat foods that have a low gycemic index to support health.
Glycemic index (GI) is a numeric value assigned to foods based on how slowly or quickly they can increase your blood glucose levels. It is a rating system for carbohydrate-containing foods. Foods having a low GI are the ones that tend to release glucose slowly and steadily. By contrast, foods that fall high on the GI scale release glucose rapidly.
Foods with a low GI help to facilitate weight loss and promote satiety. People who have or are at a risk of diabetes should eat foods with a low GI. This is because they tend to have low amounts of insulin (type 1 diabetes) or a high degree of resistance to insulin (type 2 diabetes). Insulin is the hormone that keeps the blood glucose levels under check. In its absence, blood sugars may increase when a person eats high-glycemic foods. Low-glycemic foods release sugar gradually and thus will prevent an abrupt increase in blood sugar.
GI is assigned with reference to pure glucose that is arbitrarily given a GI of 100. Thus, if a food has a GI of 30, it means it will boost blood glucose by only 30% compared with pure glucose.
What value constitutes a low glycemic index?
Low glycemic index (GI) refers to a GI value of 55 or less. Low-GI foods include most fruits and vegetables, whole or minimally processed grains, beans, pasta, low-fat dairy products and nuts.
Foods with a GI of 56 to 69 come under the category of moderate-GI foods. They include potatoes, white rice, corn, couscous and breakfast cereals such as Mini-Wheats and Cream of Wheat.
High GI means a GI of 70 or more. Foods with high GI include white bread, cakes, doughnuts, cookies, rice cakes, most crackers, bagels, croissants and most packaged breakfast cereals.
Which are the low-glycemic foods?
Some of the common low-glycemic foods are as follows
- Green peas
- Leafy greens such as spinach, collards, kale, and beet
- Green beans
- Bok choy
- Brussels sprouts
- Peppers including bell peppers and jalapeno
- Crookneck squash
- Snow peas
- Dried apricots
- Unripe banana
Whole or minimally processed grains
- Whole wheat
- Oat bran and rice bran cereals
- Whole-grain pasta
- Whole-grain pumpernickel bread
- Sourdough bread
- Wheat tortilla
Dairy and dairy-substitute products
- Plain yogurt
- Cottage cheese
- Soy milk and yogurt
- Nuts and nut butters
- Seeds such as pumpkin, chia, sunflower and flax seeds
- Poultry such as chicken and turkey
- Eggs and egg whites
- Fish and shellfish
- Meat such as beef and pork
- Oils such as extra virgin olive oil and canola oil
- Fats such as lard, shortening and butter
Medically Reviewed on 9/4/2020
Harvard Medical School