When a carbohydrate enters the digestive system, it is broken down into glucose, also known as blood sugar. Different types of carbohydrates add different amounts of glucose into the bloodstream. The glycemic index of a food indicates the amount of glucose released into the blood stream upon digesting a carbohydrate. Lower glycemic index foods are better for the body, according to the Mayo Clinic. "Slow carbs" have a low glycemic index, while "fast carbs" are carbohydrates with a high glycemic index.
High Glycemic Index Foods
High glycemic index foods are foods with a number higher than 70 on a glycemic index chart. These foods cause glucose to enter the blood stream very quickly, raising blood sugar levels quite rapidly. The quick release of glucose into the blood stream has been cited as a contributing factor to diabetes. High glycemic index foods include waffles, doughnuts, white bread, baguettes, Rice Krispies, millet, potatoes, parsnips, pretzels, dates and jelly beans, according to South Beach Diet.
Medium Glycemic Index Foods
Medium foods on the glycemic index chart include foods listed in the 55-70 range on the glycemic index chart. Medium glycemic index foods cause glucose to be released less rapidly than its high glycemic index counterparts, but still release glucose quickly enough to cause a spike in blood sugar level. According to South Beach Diet, medium foods include pastries, croissants, cheese pizza, hamburger buns, oat bran, shredded wheat, brown rice, ice cream, apricots, raisins, macaroni and cheese and popcorn.
Low Glycemic Index Foods
Low glycemic index foods are foods numbered under 55 on the glycemic index chart. Low glycemic index foods are those that release glucose very slowly into the blood stream, having little to no effect on blood sugar levels and stemming hunger pangs. Low glycemic index foods include artichoke, asparagus, celery, spinach, yoghurt, lentil soup, peanuts, carrots, spaghetti, cherries, grapefruit, milk, rye, porridge and soy milk, according to South Beach Diet.