Carb Counting and Insulin

Matching Insulin to Carbs Matching insulin doses to the amount of carbohydrates consumed helps control blood sugar levels. This advanced carb counting method also can allow those with diabetes to be able to make more food choices. Used with 3-4 daily shots of insulin or an insulin pump, matching insulin doses to carb count mimics the action of a pancreas. To do this, each individual has to figure out his or her insulin-to-carb ratio. For example, 1 unit of insulin may be needed for every 15 carbs eaten. Ratios vary between individuals and can change over time. A healthcare provider can help determine your insulin-to-carb ratio. Be sure to test blood sugar before and 2 hours after a meal

How to Use Your Insulin-to-Carb Ratio:

  1. Add up the total number of carbohydrate grams in a meal.
  2. Divide the total number of carbohydrate grams by your insulin-to-carb ratio.
  3. Inject the insulin needed to match your carbohydrate intake.

Example: Your meal has a total of 45 carbohydrate grams. Your insulin-to-carb ratio is 1 unit per 15 carbohydrate grams. So, 45 grams divided by 15 equals 3 units of insulin needed for this meal.

Insulin Correction Factor An insulin correction factor (ICF) is how many points blood sugar drops with 1 unit of insulin. ICF varies among individuals and corrects high or low pre-meal blood sugar levels. An ICF dose is either added or subtracted to the dose given before the meal. How to Use Your ICF:

  1. Subtract your target blood sugar level from current blood sugar level.
  2. Divide by your ICF.
  3. Adjust pre-meal insulin dosage accordingly.

(Current Blood Sugar - Target Blood Sugar) Insuling Correction Factor = Correction Insulin Dose Example: Your current blood sugar level is 200 and your target blood sugar level is 120. This is a difference of 80, which is divided by your ICF. If your ICF is 40, you would need 2 units of insulin to correct your current blood sugar level. Add this insulin dose to your insulin-to-carb ratio dose.