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Counting Carbohydrates When You Take Insulin: Care Instructions

Your Care Instructions

You don't have to eat special foods when you have diabetes. You just have to be careful to eat healthy foods. Carbohydrates (carbs) raise blood sugar higher and quicker than any other nutrient. Carbs are found in desserts, breads and cereals, and fruit. They're also in starchy vegetables. These include potatoes, corn, and grains such as rice and pasta. Carbs are also in milk and yogurt.

The more carbs you eat at one time, the higher your blood sugar will rise. Spreading carbs all through the day helps keep your blood sugar levels within your target range.

Counting carbs is one of the best ways to keep your blood sugar under control.

If you use insulin, counting carbs helps you match the right amount of insulin to the number of grams of carbs in a meal. Then you can change your diet and insulin dose as needed. Testing your blood sugar several times a day can help you learn how carbs affect your blood sugar.

A registered dietitian or certified diabetes educator can help you plan meals and snacks.


How can you care for yourself at home?

Know your daily amount of carbohydrates

Your daily amount depends on several things, including your weight, how active you are, which diabetes medicines you take, and what your goals are for your blood sugar levels. A registered dietitian or certified diabetes educator can help you plan how many carbohydrates to include in each meal and snack.



Count carbs

If you take insulin, you need to know how many grams of carbohydrates are in a meal. This lets you know how much rapid-acting insulin to take before you eat. If you use an insulin pump, you get a constant rate of insulin during the day. So the pump must be programmed at meals to give you extra insulin to cover the rise in blood sugar after meals.

When you know how many carbohydrates you will eat, you can take the right amount of insulin. Or, if you always use the same amount of insulin, you need to make sure that you eat the same amount of carbs at meals.

  • Learn your own insulin-to-carbohydrates ratio. You and your diabetes health professional will figure out the ratio. You can do this by testing your blood sugar after meals. For example, you may need a certain amount of insulin for every 15 grams of carbohydrates.
  • Add up the carbohydrate grams in a meal. Then you can figure out how many units of insulin to take based on your insulin-to-carbohydrates ratio.
  • Look at labels on packaged foods. This can tell you how many carbohydrates are in a serving. You can also use guides from Diabetes Canada.
  • Be aware of portions, or serving sizes. If a package has two servings and you eat the whole package, you need to double the number of grams of carbohydrates listed for one serving.
  • Protein, fat, and fibre do not raise blood sugar as much as carbs do. If you eat a lot of these nutrients in a meal, your blood sugar will rise more slowly than it would otherwise.
  • Exercise lowers blood sugar. You can use less insulin than you would if you were not doing exercise. Keep in mind that timing matters. If you exercise within 1 hour after a meal, your body may need less insulin for that meal than it would if you exercised 3 hours after the meal. Test your blood sugar to find out how exercise affects your need for insulin.

Eat from all food groups

  • Eat at least three meals a day.
  • Plan meals to include food from all the food groups.
    • Grains and starches: These include bread, cereal, rice, pasta, beans and legumes, and starchy vegetables. A serving is 1 slice bread (1 oz), 1/4 large bagel, 2/3 cup crispy rice cereal, 3/4 cup cooked wheat cereal, 1/3 cup cooked rice, 1/2 cup cooked pasta, 1/2 cup cooked beans, lentils, or peas, 1/2 cup cooked corn, or 1/2 cup mashed potatoes. These have about 15 grams of carbohydrates in a serving. Choose whole grains such as whole wheat bread or crackers, oatmeal, and brown rice more often than refined grains.
    • Vegetables: Non-starchy vegetables have about 5 grams of carbohydrates in a serving. A serving is 1 cup raw leafy vegetables, 1 cup other vegetables (cooked or chopped raw), or 1/2 cup vegetable juice.
    • Fruit: 1 small apple or medium orange, 1/2 large banana, 1/2 cup chopped, cooked, or canned fruit, 1/2 cup apple, grapefruit, orange, or cranberry juice, or 2 tablespoons raisins. These have about 15 grams of carbohydrates in a serving.
    • Dairy: 1 cup of milk or 3/4 cup of no-sugar-added yogurt. These have about 15 grams of carbohydrates in a serving.
    • Protein foods: Beef, chicken, turkey, fish, eggs, tofu, cheese, cottage cheese, and peanut butter. A serving size of meat is 3 ounces, which is about the size of a deck of cards. Examples of meat and alternatives serving sizes are 1/4 cup of cottage cheese, 1 egg, and 2 tablespoons of peanut butter. These have very little or no carbohydrates in a serving.
  • Talk to your dietitian or diabetes educator about ways to add limited amounts of sweets into your meal plan.
  • If you drink alcohol:
    • Limit it to no more than 1 drink a day for women and 2 drinks a day for men. (One drink is 341 mL of beer, 142 mL of wine, or 43 mL liquor.)
    • Make sure to count drink mixers that have sugar in your total carbohydrate count. These include cola, tonic water, margarita mix, and fruit juice.
    • Eat a carbohydrate food along with your alcoholic drink.
    • Check your blood sugar more often. This is because alcohol can lower your blood sugar too much. This may happen even hours later while you sleep. You may want to eat and adjust your insulin dose when you drink alcohol to prevent severe low blood sugar.
    • Talk to your doctor. Alcohol may not be recommended when you are taking certain diabetes medicines.

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