The glycemic index (GI) ranks foods according to the amount that they raise an individual's blood sugar level. Foods with a high GI (generally, 70 or above) digest very quickly and are rapidly absorbed, causing them to raise blood sugar levels rapidly, which can be a problem for individuals with type 2 diabetes and coronary heart disease. These foods are less healthy than low GI foods, which have proven health benefits.
Several types of breads are considered to have a high glycemic index. After eating high GI breads, blood sugar will rise very quickly. Breads that have a high glycemic index include white bread, white rolls, baguettes, bagels, black bread and gluten-free bread. Wafer biscuits fall into this category as well.
Pasta and Rice
Brown rice pasta has a very high GI. Other relatively high GI pastas include macaroni and cheese or durum wheat spaghetti. Some rices have a high glycemic index, including brown rice and jasmine rice. Rice cakes also have a high GI.
Cereal and Breakfast Foods
Breakfast cereals which are high in carbohydrate levels tend to have the highest glycemic index. These cereals include Coco Pops, Cornflakes, Puffed Wheat, Rice Krispies, Weetabix, Golden Grahams and Bran Flakes. Some cereal grains have a high GI, including barley flakes and millet. A number of breakfast and bakery products are also included in this category, including doughnuts, croissants and waffles.
When it comes to snacks, it's no surprise that many of these fall into the higher GI range. Pretzels, jelly beans and ice cream are some of the snacks with the highest glycemic index. Corn chips and soda crackers can be added to that list as well. Also, any time you add table sugar to a food, the GI increases significantly.
Fruits and Vegetables
Even though we consider fruits and vegetables to be healthy, some have a higher GI than others, including potatoes, parsnips, pineapple and watermelon. Note that while steamed, mashed, instant and baked potatoes all have a high GI, those that are boiled are actually in the intermediate GI range. Broad beans are also in this category, though technically they are a legume.