In general, foods that cause blood sugar level to rise the most are those that are high in Carbohydrates , which are quickly converted into energy, such as rice, bread, fruits and sugar. Next are foods high in Protein , such as meats, fish eggs, milk and dairy products, and oily foods. However, even though carbohydrates affect blood sugar levels, if you don't eat them your diet will be unbalanced and you won't feel satisfied after your meal, which can lead to excessive consumption of foods rich in protein and fat. Carbohydrates do raise blood sugar levels quickly. However, recent studies have shown that even amongst foods that have the same amount of carbohydrates, there are two categories: those that cause a sudden rise in blood sugar levels and those that cause a more moderate rise, depending on the amount of dietary fiber contained. Taking bread as an example, whole grain rye bread and pizza crusts are low GI foods, while French bread and bagels are high GI foods. It is impo...