Counting Carbohydrates for Diabetes: Care Instructions

Managing the amount of carbohydrate (carbs) you eat is an important part of planning healthy meals when you have diabetes. Carbs raise blood sugar more than any other nutrient. Carbs are found in grains, starchy vegetables, fruits, and milk and yogurt. Carbs are also found in sugar-sweetened foods and drinks.

The more carbs you eat at one time, the higher your blood sugar will rise. Counting carbs can help you keep your blood sugar within your target range.

If you use insulin, counting carbs helps you match the right amount of insulin to the number of grams of carbs in a meal.

Your daily amount depends on several things, such as 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 diabetes educator can help you plan how many carbs to include in each meal and snack.

Counting carbs 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. This gives you extra insulin to cover the rise in blood sugar after meals.

If you take insulin:

• Learn your own insulin-to-carb 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 carbs.
• Add up the carb grams in a meal. Then you can figure out how many units of insulin to take based on your insulin-to-carb ratio.
• 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.

If you do or don't take insulin:

• Look at labels on packaged foods. This can tell you how many carbs are in a serving.
• 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 carbohydrate listed for one serving.
• Protein, fat, and fiber do not raise blood sugar as much as carbs do. When you eat a meal that contains these nutrients along with carbohydrates, your blood sugar will rise more slowly than it would otherwise.