Diabetes: Counting carbs if you use insulin

Carbohydrate counting helps prevent low or high blood sugar levels, which can cause medical emergencies. Over time, high blood sugar levels can damage many body tissues and organs.

Counting carbohydrate grams allows you to match insulin to the food you eat every day to keep blood sugar at your target level. This method is effective because carbohydrate is the main nutrient that causes blood sugar to rise after meals, increasing the need for insulin. Carbohydrate turns into glucose within 2 hours after you eat.

If you use an insulin pump or take multiple insulin injections, you need to know how many grams of carbohydrate are in a meal to calculate how much rapid-acting insulin to take before you eat. A pump provides a continuous (also known as basal) rate of insulin throughout the day, but it must be programmed at meals to provide extra insulin to allow for the rise in blood sugar after meals. When you know how much carbohydrate you will eat, you can program extra units, or boluses, of insulin to cover your meals.

You figure out how much insulin to use based on your own insulin-to-carbohydrate ratio. This ratio may be different from one person to another, and even your own ratio may change over time. You and your doctor will calculate the ratio by recording the food you eat and testing your blood sugar after meals.

Continue to How do I count carbohydrate grams in my diet?

Return to Diabetes: Counting carbs if you use insulin