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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.

Follow-up care is a key part of your treatment and safety. Be sure to make and go to all appointments, and call your doctor or nurse call line if you are having problems. It's also a good idea to know your test results and keep a list of the medicines you take.

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.

For most adults, a guideline for the daily amount of carbohydrates is:

  • 45 to 60 grams at each meal. That's about the same as 3 to 4 carbohydrate servings.
  • 15 to 20 grams at each snack. That's about the same as 1 carbohydrate serving.

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 a variety of foods every day

  • Eat at least three meals a day.
  • Talk to your dietitian about planning the amounts of carbohydrate that will work best for you.
  • Put vegetables and fruits on half the plate. Add a protein food on one-quarter of the plate, and put a whole grain food on the final quarter of the plate. Make water your drink of choice.
  • Here are some examples of carbohydrate servings:
    • Grains (whole grain foods) and starchy foods: These have about 15 grams of carbohydrates in a serving. Choose whole grain foods such as whole grain bread or crackers, oatmeal, and brown rice more often than refined grains. A serving is 1 slice bread (30g, or 1 oz), 1/4 large bagel, 155ml (2/3 cup) crispy rice cereal, 175ml (3/4 cup) cooked oatmeal, 80ml (1/3 cup) cooked rice, 125ml (1/2 cup) cooked pasta, 125ml cooked beans, lentils, or peas, 125ml cooked corn, or 125ml mashed potatoes.
    • Vegetables: Non-starchy vegetables that are low in carbohydrates. Choose a variety of colours. Low carbohydrate vegetables include; 250ml (1 cup) raw leafy vegetables, or 250ml other vegetables (cooked or chopped raw).
    • Fruits: These have about 15 grams of carbohydrates in a serving. Choose a variety of colours. A serving is 1 small apple or medium orange, 1/2 large banana, 125ml (1/2 cup) chopped, cooked, or canned fruit, 125ml apple, grapefruit, orange, or cranberry juice, or 30ml (2 tablespoons) raisins.
    • Protein foods (milk and alternatives): These have about 15 grams of carbohydrates in a serving. A serving is 250ml (1 cup) of milk, 175ml (3/4 cup) of no-sugar-added yogurt, or 250ml of plain, fortified soy beverage.
    • Protein foods (meat and alternatives): These have very little or no carbohydrates in a serving. A serving is 75 grams of meat, poultry, or fish, 60ml (1/4 cup) of cottage cheese, 1 egg, or 2 tablespoons of peanut butter.
  • 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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