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
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
Test Your Knowledge
Carbohydrate counting helps me know how much insulin I
need to take at meals.
Continue to How do you count carbohydrate grams in your diet?
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