Diabetes: Counting Carbohydrates Meal Plan

What is the counting carbohydrates meal plan?

Counting carbohydrates is a food plan that involves adjusting your insulin dose according to the amount of carbohydrates you plan to eat. Carbohydrates (carbs) affect your blood sugar level more than any other kind of nutrient. Insulin works with carbohydrates to supply energy for your body. The main goal of this food plan is to balance insulin with the carbohydrates you eat throughout the day.

How is this plan different from the exchange or constant carbohydrate meal plans?

This plan is different from the exchange meal plan or constant carbohydrate plan because the insulin dosage and carbohydrates are not always the same day to day. This plan is more flexible. You may choose to start using this plan after you have learned more about your body's responses to your food choices and you have become comfortable with the use of insulin.

How does this plan work?

First, you and your healthcare provider need to figure out how much insulin you need to take in relation to the amount of carbohydrate you plan to eat. There are 2 approaches to take when figuring this out:

• Units per carb choice (exchange): Count carbohydrates in portion sizes of 15 grams. This is called a carb choice or an exchange. Your provider will tell you how many units of insulin you need for every carb choice that you eat.

  To determine how many carb choices you are eating, divide the number of grams of carbohydrate in a food by 15. For example, if a container of yogurt with fruit has 45 grams of carbohydrate in it, it contains 3 carb choices.

  You will adjust the units of short-acting insulin for every meal to match the number of carb choices you are eating. For example, if you need 1 unit of insulin for every carb choice, then for 3 carb choices, you need 3 units of insulin.

  Units of insulin per carb choice times the number of carb choices = total units of insulin needed.

• I/C ratio: More commonly people use an insulin-to-carbohydrate ratio (I/C ratio) to calculate how much insulin to take. If you use a ratio, you need to count the grams of carbs you are eating, but you do not need to convert the grams to carb choices. An example of an I/C ratio is 1 unit of insulin for every 10 grams of carbs you eat.

  For example, if you plan to eat 60 grams of carbohydrate and your I/C ratio is 1/10 (0.10), then you need 6 units of insulin (60 X 0.10 = 6).

  Grams of carb times I/C ratio = units of insulin.

  Your dietitian will help you figure out your I/C ratio.

When will I need to make more adjustments to the insulin dose?

After you calculate the number of units of insulin you need to take for the amount of carbs you are eating, you may need to adjust the dose further. These adjustments are based on planned exercise, blood sugar levels, or other factors that may affect blood sugar such as illness, stress, or menstrual periods. For example, you may need to reduce the dose of insulin if your blood sugar level is low (below 70 mg/dL, or 3.9 mmol/L). You may need a higher dose if your blood sugar is too high (above 200 mg/dL, or 11.1 mmol/L). The insulin dose calculated from the I/C ratio is usually reduced by half if it is given before strenuous exercise or at bedtime. Your dietitian and healthcare provider will give you guidelines for making adjustments.

Which foods have carbohydrates?

Carbohydrates are found in many foods including:

• starchy foods (such as breads, cereals, rice, starchy vegetables, and pasta)
• fruit
• milk and yogurt
• sweets.

Most vegetables, meats, and fats are not high in carbohydrates, so they affect blood sugar levels less than carbs. You can adjust your insulin dose based on meats and fats, if needed, after you have learned how to count carbohydrates.

To see a list of carb choices, you can order the Exchange List for Meal Planning from The American Diabetes Association and the American Dietetic Association (1-800-342-2383). Although this book is often used for the exchange diet, it lists the carbohydrate content for lots of foods and is very useful for this plan as well. Nutrition labels on food packages also list the grams of carbohydrate in a serving of food.

When should I take insulin?

In general, you should take insulin at a time that allows the insulin to start working as your blood sugar begins to rise. Sugar is absorbed into the blood about 10 minutes after eating. The peak in blood sugar from food usually happens about 60 minutes after you eat.

• Humalog, NovoLog, or Apidra begins working in 10 minutes. The peak activity of this insulin happens 100 minutes (less than 2 hours) after you take it. Take this type of insulin 15 to 30 minutes before you eat (if your blood sugar is more than 80 mg/dL, or 4.5 mmol/L).
• Regular insulin begins working in 20 to 30 minutes. The peak activity is 2 to 4 hours after you take it. Take this insulin 30 to 60 minutes before you eat.

Sometimes you can take insulin after you eat. Your healthcare provider and dietitian will help you create a schedule for your meals and insulin doses.

How do I get started?

1. Keep a careful record of food, insulin, blood sugar level, and exercise for at least 3 days. Measure and record your blood sugar before meals and 2 hours after meals. Record all doses of insulin or oral medicines you take.
2. The dietitian will analyze the report and work with your healthcare provider to decide how much insulin you need to take for the amounts of carbohydrates you eat.
3. Start counting carbs and adjusting the insulin dose accordingly. For the first 1 to 2 weeks carefully record the following:
   • the number of carbohydrates you eat at each meal or snack
   • your insulin doses
   • your blood sugar levels (especially 2 hours after meals when levels should be less than 180 mg/dL, or less than 10 mmol/L).
4. After a week or two, review your records with your dietitian to see if any adjustments need to be made. If the blood sugar values are not in the desired range, then your insulin doses need to be changed.