Diabetes: Understanding Carbohydrates

Brian King11/ 4/14

Just as a car needs the right type of fuel (gas) to run, you need the right kind of fuel (food) to function. To sustain energy, your body needs food that contains carbohydrates. But carbohydrates raise blood sugar levels higher and faster than other kinds of food. Your dietitian will probably recommend that 50-60% of your calories come from carbohydrates.


Starches are found in grains, some vegetables, and beans. Grain products include bread, pasta, cereal, and tortillas. Starchy vegetables include potatoes, peas, corn, lima beans, yams, and squash. Kidney beans, pinto beans, black beans, garbanzo beans, and lentils also contain starches.


Sugars are found naturally in many foods. Or sugar can be added. Foods that containnatural sugar include fruits and fruit juices, dairy products, honey, and molasses. Addedsugars are found in most desserts, processed foods, candy, regular soda, and fruit drinks.


Fiber comes from plant foods. Most fiber isn’t digested by the body. Instead of raising blood sugar levels like other carbohydrates, it actually keeps blood sugar from rising too fast. Fiber is found in fruits, vegetables, whole grains, beans, peas, and many nuts.

Carb Counting

You can learn to figure out how many carbohydrates you are eating every day. Ask your dietitian to teach you a technique called “carb counting.” This system helps you keep track of the carbohydrates you eat at each meal. There are different ways to do carb counting. Basic carb counting is described below. This method is a good way to get started with carb counting.

  • When you count carbohydrate servings, one serving of a starch, fruit, or dairy product counts as one “carb.”
  • Each carb is about 15 grams of carbohydrate. For example:

    • 1 slice of bread = 1 starch serving = 15 grams of carbohydrate
    • 1 apple = 1 fruit serving = 15 grams of carbohydrate
    • 1 cup milk = 1 dairy serving = 15 grams of carbohydrate
  • Your dietitian will help you determine how many carbohydrate servings to have at each meal and snack.