Carb Counting 101
By Nina Nazor
What is carb counting?
Carbohydrate counting is a method for calculating the grams of carbohydrates you eat to make
your diet more flexible and easier to follow. You need to work with your doctor and/or dietitian to find out how many carbohydrate
grams or carbohydrate choices you should eat each day.
grams or carbohydrate choices come from foods that contain carbohydrates.
you take pills or insulin, counting carbs might work for you. If you try to eat the same amount of carbohydrates in each of
your daily meals, you will notice a pattern in your postprandial (2 hours after meals) blood glucose test results. This will
allow you to adjust food, exercise and/or medication to keep blood glucose levels under control.
To determine how a particular meal affects your blood glucose levels, you should check your glucose two hours after
the first bite of food. Try to keep your after-meal blood glucose levels below 180. If your levels are too high, then you
may want to reduce the amount of carbohydrate that you eat in that meal, do more exercise or use more medication (this only
with your doctor's approval). Making the best choices with this information will allow you to achieve better blood glucose
What foods contain carbohydrates?
Carbohydrates are found in starches and sugars. The following foods contain carbohydrates:
Breads, cereals, and crackers
· Rice, pasta, oatmeal, corn and grains
Many snack foods like chips
· Dried beans and lentils
Starchy vegetables like potatoes, sweet corn, green peas, sweet potatoes, winter squash
Non-starchy vegetables (some contain more carbs than others)
Fruit and fruit juice
· Milk and yogurt
Sugar, honey, syrup, sweets, and desserts
is a carbohydrate choice or exchange?
the nutrients that most affect blood glucose levels. The main goal of carb counting is to balance insulin with the carbohydrates
you eat in each meal. For this you will need to use “carbohydrate choices” or “carbohydrate exchanges”.
If you are familiar with the exchange system, you can easily use this method.
A “carb choice” or “carb exchange” is a portion of food containing
15 grams of carbohydrates.
· 1 starch exchange = 15 grams carbs = 1 choice
· or 1 fruit exchange = 15 grams carbs = 1 choice
or 1 milk exchange = 12 grams carbs = 1 choice
· or 3 vegetable exchanges
= 15 grams carbs = 1 choice
· or 1 other carbohydrate exchange (15 grams carbs)[
· 1 fat exchange = 0 grams carbs = 0 choice
1 protein exchange = 0 grams carbs = 0 choice
is a starch exchange?
The starch list contains breads, cereals,
rice, pasta, crackers, grains, starchy vegetables (potatoes, corn, green peas, sweet potatoes, and winter squash), dried beans
and lentils and many snacks.
One starch exchange contains 15 grams of carbohydrates.
In general one starch exchange is:
1/2 cup of cooked cereal, grain or pasta
· 1/2 cup cooked starchy
vegetables like potato, corn, green peas, sweet potato, winter squash
1 ounce of a grain product, for example 1 slice of bread, 1 small tortilla or 1 ounce dry cereal
1/2 cup cooked beans or lentils
· 3/4 to 1 ounce of most snack foods; however,
some snack foods also have fat.
What is a fruit exchange?
The fruit list contains fruits and fruit juices.
One fruit exchange contains 15 grams of carbohydrates.
In general 1 Fruit exchange is:
· 1 small to medium fresh fruit (maximum the amount
that would feet in your hand)
· 1/2 cup canned fruit
1/2 cup fruit juice
· 1/4 cup dried fruit
What is a milk exchange?
milk list contains milk and yogurt. Cheese is not included in the milk list, because cheese is higher in fat and protein content.
Cheese is included in the meat and meat substitute group.
One milk exchange
contains 12 grams of carbohydrates.
In general 1 milk exchange is:
1 cup milk (240 ml or 8 ounces)
· 1 cup of nonfat or low-fat fruit-flavored yogurt
with a non-nutritive sweetener
What is a vegetable
The vegetable list contains vegetables and vegetable
Starchy vegetables including potatoes, green peas, corn, sweet potatoes,
and winter squash are not in the vegetable list but in the starch list.
takes three vegetable exchanges to make one carb choice.
One vegetable exchange
contains 5 grams of carbohydrates.
In general 1 vegetable exchange is:
1 cup raw vegetables
· 1/2 cup cooked or canned vegetables
1/2 cup vegetable juice
How do I calculate
the carb choices of a packaged food?
You can use food labels
to estimate carb choices. You may use the “total carbohydrate” information to determine the number of carb choices
in each serving.
Just divide the number of grams of carbohydrate in a food
by 15 to determine the amount of carb choices.
For example, if a container
of yogurt with fruit has 45 grams of carbohydrate in it, then it would contain 3 carb choices.
What are insulin to carbohydrate ratios?
If you take insulin, insulin to carbohydrate (I:C) ratios are used to calculate how much insulin you'll need
to help your body metabolize (process) the carbs in a meal.
if your ratio is 1:15, you'll need 1 unit of insulin for every 15 grams of carbs you eat.
An "average" can be 1 unit of insulin for every 10 or 15 grams of carbs for an adult, or 1 unit for every
20 to 30 grams for a school-age child.
Your Diabetes Care Team must help
you establish your personal I:C ratios or in other words, how many units of insulin you need for every carb choice or specific
amount of carbs in grams, you plan to eat.
If you use insulin, the units
of short acting insulin (Humalog/NovoLog or Regular) are adjusted at every meal to match the number of carb choices or carb
For example, if you need 1 unit of insulin for every carb choice,
then for 2 carb choices, you would need 2 units of rapid or regular insulin.
How do I know the amount of carbs I should eat in a day?
In general, the American Diabetes Association recommends the following amount of carbs each day:
12 carbohydrate choices or 180 grams for a weight loss plan of 1200-1500 calories
13 carbohydrate choices or 195 grams for most women (1400-1700 calories)
16 carbohydrate choices or 240 grams for most men (1800-2300 calories)
You should distribute them throughout the day in 3 meals and 1 or 2 snacks.
Source: American Diabetes Association and American Dietetic Association. Carbohydrate Counting Getting Started, Alexandria,