Food is made of carbohydrates, proteins, and fat. Each of these is digested and broken into smaller parts. Once broken down, these parts will affect blood glucose differently. How these parts affect blood glucose depends on how they are absorbed and how the body uses them. Almost all the carbohydrate eaten will be converted into glucose in the body. The only carbohydrates not changed to glucose are those that cannot be digested, like fiber.
Foods with carbohydrates include those in the fruit group, such as bananas, oranges, apples, and peaches. Dairy products such as milk, yogurt, and ice cream also have carbohydrates. Although part of the dairy group, cheese is not high in carbohydrate. Cheese is higher in protein and fat, and may be thought of as a protein food, such as meat. Breads, cereals, pastas, rice, and crackers are rich in carbohydrates. Vegetables have carbohydrates, but at low amounts.
Carbohydrates affect blood glucose, because carbohydrates are digested and broken into smaller parts that are primarily glucose units. Glucose is not bad for people with diabetes. Everyone, including people with diabetes, needs glucose for energy. We need energy to play, exercise, and work, but we also need it for everyday body functions, like breathing, digesting, and making blood cells. Most of the glucose in our body comes from eating carbohydrates. People without diabetes are able to keep their blood glucose levels in a normal range regardless of the amount they eat.
For people with diabetes, it is harder to keep blood glucose in a normal range. For this reason, people with diabetes need to balance the amount of food that they eat (especially food that contains carbohydrates) with their medication and activity level.