An Overview of Carb Counting

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To meet health goals and still maintain flexibility with meal planning, many people with diabetes rely on the carb counting method. Carb counting involves reading food labels or researching nutrition facts to find out how many grams of carbohydrates are in a serving of the food you're eating, then keeping track of the total grams consumed in each meal to meet a target goal.

The Importance of Carbs for People With Diabetes

Carbohydrates are a primary source of glucose (sugar), which is used as fuel by every system and cell in the body. But because carbs consist of sugar, consuming them can flood your bloodstream with glucose. If you have diabetes, this may affect your blood sugar balance and insulin levels. Carb counting is a measured way of keeping your carb intake in check, so as not to throw off your glucose control.

Pros and Cons of Carb Counting

Carb counting is an easy way to follow a low-carb diet, but the quality of food you're eating still plays a big role in your overall health.

Pros of Carb Counting
  • Carb counting can be a helpful application for those looking to follow a low-carb diet

  • Nutrition labels on packaged foods make it easy to count carbs

  • Keeping a target carb number in mind is a tangible measure of how much to eat

Cons of Carb Counting
  • Keeping track of carbohydrates alone does not necessarily equate to a healthy diet

  • It may be easier to rely on packaged foods with nutrition labels than whole foods like fruits and vegetables, which don't have carbs listed on them

  • Not all foods contain carbohydrates, but still may be high in calories and fat, such as steak or bacon—this can become hard to track if you're only counting carbs

The takeaway here is that carb counting can be a healthy way to manage blood sugar and make it easy to visualize and keep track of your intake, but that the quality of the carbs you're eating does matter. For best results, focus your carb choices on high-quality, less processed foods such as whole grains, fresh or frozen fruit, and vegetables.

Methods of Carb Counting

There are two primary methods of carb counting. Learn more, then pick the style that works for you.

Diabetic Exchange System

If you're using the diabetic exchange system, you will have a meal plan, usually provided by a dietitian, that breaks down the food you can have with each meal as choices. For instance, you might have one carbohydrate choice and one lean protein choice. One carbohydrate choice is usually equal to 15 grams of carbohydrate (or often, 10 to 15 grams). 

The exchange system does the math for you. Rather than reading labels and calculating carbs, the diabetic exchange lists provide you with "choices" that are roughly equal to each other in terms of carbohydrate (and, for the other categories, including vegetables, proteins, and fat).

A carbohydrate choice should equal 80 calories, 15 grams of carbohydrate and zero grams of fat. That doesn't mean that every carbohydrate choices is the same serving size. For instance, each of these servings of food is equivalent to one carbohydrate choice:

  • 3 cups of popcorn
  • 1 slice of bread (1 ounce)
  • 1/2 cup cooked pasta

Carb Counting (Target Grams)

With this method of meal planning for diabetes, instead of shooting for a target number of carbohydrate servings at each meal, you'll have a target for grams of carbohydrate. As an example, many people might be targeting between 45 and 60 grams of carbohydrate for a meal and 15 to 30 grams of carbohydrate for a snack.

If you'd like to then translate the total grams of carbohydrate in a serving of food into "carbohydrate servings," you can take the total number of grams of carbohydrate and divide by 15.

For instance, say you want to figure out how many carb servings are in a serving of lasagna. If you look up lasagna in the nutrient database, you'll see that a 1 cup serving has 31 grams of carbohydrate. Divide by 15 and you get 2 (it's okay to round up or down to the closest whole number). So that 1-cup serving of lasagna is worth two carbohydrate servings.

Getting Started

There are a few key steps to take before you're ready to begin:

  • Calculate your customized goal. Remember that everyone's individual needs are different. Work with your healthcare team, including a registered dietitian and your doctor to set a carb target for yourself, then get familiar with serving sizes, nutrition labels, and the carb values of common foods to keep a running tally. For example, if your target intake is 45g carbs per meal, you'll need to add up the carb count of your meal components so as not to go over 45g.
  • Compile your resources. Get familiar with label-reading, and start to look up nutrition facts on the USDA's food composition database to find how many grams of carbohydrates are in a serving of the food you eat.
  • Keep a log. Keeping a running mental carb tally can be tricky to remember, which is why it's helpful to start a food diary where you can log your carb intake for each meal and snack. For some people, a notebook and pen are best, for others, updating a digital note on your phone or using an app (see more below) may be simpler.

Carb Counting Apps

There are several great (and free!) carb counting apps available to help you keep track of your intake with easy, on-the-go access.

Carb Manager

A simple-to-use carb tracker, this app offers basic carb tallying, helping you account for over 1 million foods. Take a look at your averages with handy graph analyses, plus get access to over 1,000 low-carb recipes, Carb Manager also syncs with most fitness trackers. The app is free to download and use but also offers a premium paid subscription for additional services.


An all-around food and fitness tracking app, MyFitnessPal is a straightforward way to log your daily meals and keep a running count of not only carb intake, but protein, fat, and micronutrients, too. App notifications provide helpful reminders to enter your food choices each day. The app is free to download and use.

MyPlate Calorie Tracker

One part carb/calorie counter, one part social media app, the MyPlate Calorie Tracker is an easy-to-use food tracker with a built-in social community that provides extra motivation and support to help you reach your health and fitness goals. The app is free to download and use but also offers a premium paid subscription for additional features.

Things to Remember When Carb Counting

Keep the lines of communication open with your healthcare team and be sure to reach out to them with any questions, but here are a few helpful tips.

Recognize all carbs: Think beyond bread and crackers: milk, yogurt, fruit, sugar, and starchy vegetables are all sources of carbs, too.

Follow the serving size: When reading labels, don't forget to look at the suggested serving size at the top of the Nutrition Facts label. That number should be able to tell you the approximate portion you should be eating and how to effectively count those carbs.

Try not to stress: Carb-counting may seem daunting, but it's really just a tool to help you practice mindful eating. Don't focus too much on the numbers if they cause you to stress about what you're eating: just aim for a general target number and focus instead on reaching for whole grains, complex carbs, and fresh fruits and veggies.

Remember the rule of 15: Most fruit, vegetables, and starches (1 c squash, 1 ear of corn, 1 small white potato) have around 15g carbs per serving, which is a good rule of thumb to remember for foods without a label.

Get familiar with portion sizes: The ability to accurately eyeball portion sizes without a scale is a highly useful skill when you're out to eat.

Consider investing in tools: While not essential for carb-counting success, measuring cups and a small food scale will help you keep an accurate count and stay on top of portion sizes at home.

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