What is the counting carbohydrates meal plan?
Counting carbohydrates is a meal
plan that involves matching your insulin dose to the amount of carbohydrates
(carbs) you eat. Carbs supply energy for your body and affect your blood
sugar level more than any other nutrient. The main goal of this food plan
is to balance your insulin dose with the carbohydrates you eat.
How is this plan different from the
exchange or constant carbohydrate meal plans?
This plan is different because
the insulin dose and carbohydrates are not always the same day to day. This
plan is more flexible. Most people start using this plan after they are familiar
with how their body responds to food choices and have become comfortable
with insulin.
How does this plan work?
First, you and your health care
provider need to figure out how much insulin you need to balance the amount
of carbohydrate you eat. There are two ways to figure this out:
- Units per carb choice (exchange): Count carbohydrates in portion sizes of 15 grams
(this is called a carb choice or an exchange). You take a set number of
units for every carb choice that you eat.
To find out how many carb choices
you eat, 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,
it contains 3 carb choices.
You then take the units of rapid
or short-acting insulin (Humalog/NovoLog or Regular) you need 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 (1 x 3 = 3).
Units of insulin per carb choice
x the number of carb choices = total units of insulin.
- I/C ratio: Other
people use an insulin-to-carbohydrate ratio (I/C ratio) to figure out how
much insulin to take. If you use a ratio, you still need to count the grams
of carbs but you do not need to convert the grams to carb choices. You
base the dose on grams of carbohydrates.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 x I/C ratio = units
of insulin.
You can work with your health care
team to figure out your I/C ratio.
Will I need to make more adjustments
to the insulin dose?
After you figure out the number
of units of insulin you need to take for the amount of carbs you eat, 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). You may need to increase the dose if your blood sugar is too high
(above 180 mg/dl). Your dietitian and health care provider will give you
guidelines for making these adjustments. The
insulin dose calculated from the I/C ratio is usually reduced if it is given
before strenuous exercise or at bedtime.
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.
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. Nutrition labels on food packages
also list the grams of carbohydrate in a serving of food.
When should I take insulin?
In general, you need to take insulin
at a time that allows the insulin to start working as carbohydrates are absorbed
into the blood. Your blood sugar starts to rise about 10 minutes after you
start to eat.
- Humalog/NovoLog begins
working in 10 minutes. The peak activity of this insulin is 30 to 90 minutes
after you take it. Take this insulin right before you eat.
- Regular insulin begins
working in 20 to 30 minutes. The peak activity is 2 to 4 hours after taking.
Take this insulin 20 to 30 minutes before you eat.
How do I get started?
- Keep a careful record of food, insulin, blood
sugar levels, and exercise for at least 3 days. Measure your blood sugar
2 hours before meals and 2 hours after meals. Record all doses of insulin
or oral medicines you take.
- You and your health care team will analyze
the report and decide how much insulin you need to take to balance the
amount of carbohydrates you eat.
- Start counting carbs and give insulin to
match. It helps to keep careful records for the first 1 to 2 weeks of:
· the
number of carbohydrates you eat at each meal or snack
· your
insulin doses
· your
blood sugar levels (especially 2 hours after meals).
- If the blood sugar values are not in your
target range, then your insulin doses need to be changed. Review your
records with your team to see if any adjustments need to be made. Your
insulin doses may need to be adjusted periodically.
This
information is approved and/or reviewed by U-M Health System providers
but it is not a tool for self-diagnosis or a substitute for medical
treatment. You should speak to your physician or make
an appointment to be seen if you have questions or concerns about
this information or your medical condition.