Understanding Carbohydrates

Bread, pasta, and grains.

A car needs the right type of fuel to run. And you need the right kind of food to function. To keep your energy level up, your body needs food that has carbohydrates. But carbohydrates raise blood sugar levels higher and faster than other kinds of food. Your dietitian will work with you to figure out the amount of carbohydrates you need.


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 contain natural sugar include fruits and fruit juices, dairy products, honey, and molasses. Added sugars are found in most desserts, processed foods, candy, regular soda, and fruit drinks. These are very helpful for treating low blood sugar, or hypoglycemia. They provide sugar quickly. Try to keep at least 15 to 20 grams of these simple sugars with you at all times. Eat this if you begin to have low blood sugar symptoms.


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

Carb counting

Keep track of the amount of carbohydrates you eat. This can help you keep the right balance of physical activity and medicine. The amount of carbohydrates needed will vary for each person. It depends on many things such as your health, the medicines you take, and how active you are. Your healthcare team will help you figure out the right amount of carbohydrates for you. You may start with around 45 to 60 grams of carbohydrate per meal, depending on your situation. Carb counting is a system that helps you keep track of the carbohydrates you eat at each meal.

Carbohydrates come from a variety of foods. These include grains, starchy vegetables, fruit, milk, beans, and snack foods. You can either count carbohydrate grams or carbohydrate servings. When you count carbohydrate servings, 1 carbohydrate serving = 15 grams of carbohydrates.

Here are some examples of foods containing about 15 grams of carbohydrates (1 serving of carbohydrates):

  • 1/2 cup of canned or frozen fruit

  • A small piece of fresh fruit (4 ounces)

  • 1 slice of bread

  • 1/2 cup of oatmeal

  • 1/3 cup of rice

  • 4 to 6 crackers

  • 1/2 English muffin

  • 1/2 cup of black beans

  • 1/4 of a large baked potato (3 ounces)

  • 2/3 cup of plain fat-free yogurt

  • 1 cup of soup

  • 1/2 cup of casserole

  • 6 chicken nuggets

  • 2-inch-square brownie or cake without frosting

  • 2 small cookies

  • 1/2 cup of ice cream or sherbet

Carb counting is easier when food labels are available. Look at the label to see how many grams of total carbohydrates the food contains. Then you can figure out how much you should eat.

Two very important lines to look at on the label are the serving size and the total carbohydrate amount. Here are some tips for using food labels to count your carbohydrate intake:

  • Check the serving size. The information on the label is based on that serving size. If you eat more than the listed serving size, you may have to double or triple the other information on the label. 

  • Check the total grams of carbohydrates. Total carbohydrate from the label includes sugar, starch, and fiber. Be sure to use the total carbohydrate number and not sugar alone.

  • Know how many grams of carbohydrates you can have.  Be familiar with the matching portion sizes.

  • Compare labels. Compare the labels of different products, looking at serving sizes and total carbohydrates to find the products that work best for you. 

  • Don't forget protein and fat. With all the focus on carb counting, it might be easy to forget protein and fat in your meals. Don't forget to include sources of protein and healthy fat to balance your meals.

It’s also important to be consistent with the amount and time you eat when taking a fixed dose of diabetes medicine. Work with your healthcare provider or dietitian if you need additional help. He or she can help you keep track of your carbohydrate intake. He or she can also help you figure out how many grams of carbohydrates you should have.