White bread, energy drinks sweetened with glucose, corn products, fruit-flavored candy, white rice, whole wheat bread and potatoes are foods with the highest glycemic number. Chickpeas, peanuts, unprocessed whole wheat kernels and unsweetened dairy products are foods with very low glycemic numbers.
A food's glycemic number is a measure of how strongly it affects the body's blood sugar. The lower the glycemic number, the less impact the food has on blood sugar and insulin levels in the people who consume it. Foods with a glycemic number lower than 55 are considered to be low on the glycemic index, and are healthy for most diabetics and dieters to eat. Unprocessed whole grains, acidic fruits and foods high in protein and healthy fats are all low on the glycemic index.
The glycemic number of a food can change with age or preparation. Fruits rise higher on the glycemic index as they ripen, and the longer pasta cooks the higher its glycemic number is. Conversely, cooking methods that add fats, fiber or acid lower the glycemic number of the finished dish. Eating foods lower on the glycemic index as part of a complete meal also lowers the impact of foods with high glycemic numbers.