Glycemic Index 101

Curious what the glycemic index actually means and if it’s relevant to you? Find out here what it is and why you should keep it in mind when shopping and eating.

Glycemic index and glycemic load offer information about how foods affect blood sugar and insulin. The lower a food’s glycemic index (or glycemic load), the less it affects blood sugar and insulin levels.

The glycemic index (GI) is a ranking of carbohydrates on a scale from 0 to 100 according to the extent to which they raise blood sugar levels after eating. Foods with a high GI are those which are rapidly digested and absorbed and result in marked fluctuations in blood sugar levels. You can view an extensive list here.

Low-GI foods, by virtue of their slow digestion and absorption, produce gradual rises in blood sugar and insulin levels, and have proven benefits for health. Low GI diets have been shown to improve both glucose and lipid levels in people with diabetes (type 1 and type 2). They have benefits for weight control because they help control appetite and delay hunger. Low GI diets also reduce insulin levels and insulin resistance.

Examples:
Low GI Foods (55 or less): 100% stone-ground whole wheat or pumpernickel bread, oatmeal (rolled or steel-cut), oat bran, muesli, pasta, converted rice, barley, bulgar, sweet potato, corn, yam, lima/butter beans, peas, legumes and lentils, most fruits, non-starchy vegetables and carrots

Medium GI (56-69): Whole wheat, rye and pita bread, quick oats, brown, wild or basmati rice, couscous

High GI (70 or more): White bread or bagel, corn flakes, puffed rice, bran flakes, instant oatmeal, shortgrain white rice, rice pasta, macaroni and cheese from mix, russet potato, pumpkin, pretzels, rice cakes, popcorn, saltine crackers, melons and pineapple

What’s the difference between glycemic index and glycemic load? The glycemic load takes into account serving size.

Glycemic Load gives a relative indication of how much a serving of food is likely to increase your blood-sugar levels. Glycemic load estimates the impact of carbohydrate consumption using the glycemic index while taking into account the amount of carbohydrate that is consumed. For example, watermelon has a high GI, but a typical serving of watermelon does not contain much carbohydrate, so the glycemic load of eating it is low.

As a rule of thumb, most nutritional experts consider Glycemic Loads below 10 to be “low,” and Glycemic Loads above 20 to be “high.” Because Glycemic Load is related to the food’s effect on blood sugar, low Glycemic Load meals are often recommended for diabetic control and weight loss.  Click here for examples of glycemic load.