Low-glycemic foods are any foods that are rated low on the glycemic index (GI), a numeric rating system that tells you how individual foods affect your blood sugar levels. On a scale of 0 to 100+, a low-glycemic food has a GI rating of 50 or less. Since low-GI foods do not raise blood sugar levels as high as medium- and high-GI foods, less of the hormone insulin is required to remove sugar from the blood. As a result, low-GI foods help control type 2 diabetes and weight. The only foods that have GI ratings are carbohydrates, including fruits, vegetables, grains and grain products, dairy foods, legumes, nuts and sugars.
Since there are many different varieties of fruits, and fruit comes in a variety of forms, such as fresh, canned, juiced and dried, each type has its own GI value. Whole fruit, such as an orange with a GI rating of 43, may be a low-glycemic food; but its juice, such as orange juice with a glycemic rating of 52, has a more moderate GI rating. Low-glycemic fruits and fruit juices with GI ratings less than 50 include bananas, oranges, apples, apple juice, pears, fresh apricots, dried apricots and grapefruit.
Most vegetables are low- to very low-glycemic foods. Most starchy vegetables, such as white and sweet potatoes, beets, rutabaga and corn, are medium to medium-high on the glycemic index. Green peas, with a GI value that ranges from 48 to 70, depending on the variety, have the lowest value of the common starchy vegetables. Of the non-starchy vegetables, carrots have the highest GI value, 49, which is still considered low. Most other non-starchy vegetables such as broccoli, spinach, peppers, cabbage and onions have GI values well under 50.
Grains and grain foods such as breads, rolls, and ready-to-eat and cooked cereals tend to have high GI values. This food group also includes snacks, desserts and other highly processed foods, most of which are high-glycemic foods. Bulgur wheat, converted rice and barley are low-glycemic whole-grain foods. Grain products that are also low on the GI scale include both regular and whole-wheat spaghetti, 100% wheat bran cereals and whole-grain pumpernickel bread.
All milk and milk products, including fruit-flavored yogurts and even chocolate milk, are low-glycemic foods. Whole milk has a GI value of 27, skim milk has a GI value of 32 and chocolate milk, 34. Low-fat fruit yogurt has a GI value of 33. More than with other foods, these are approximate values, given the wide variety of products and flavors available.
Legumes and Nuts
Legumes include cooked dried beans, lentils and split peas. Soy beans are a very low-glycemic food, with a GI value of 18. Peanuts, which are technically legumes that grow underground, have a GI value of 14. White beans, black beans, kidney beans, garbanzo beans and all other legumes are low-glycemic foods, with GI values ranging from the high 20s to the low 30s. Even prepared baked beans are low-glycemic foods, with a GI value of 48.
Fructose, or fruit sugar, is a low-glycemic sweetener with a GI value of 43. Most other sugars and natural sweeteners are moderate- to high-glycemic foods. Honey has a GI value of 58, and sucrose, or table sugar, has a GI value of 65. Pure glucose, the sugar that remains when carbohydrates are broken down by the body for digestion and absorption, is a form of sugar that is readily absorbed into the bloodstream. For that reason, it is also the food against which all others are compared and measured on the glycemic index.