You may have heard that people with type 2 diabetes should limit or avoid foods high in carbohydrates. This is because carbohydrates are nutrients that have the greatest impact on blood glucose levels. Diabetes can throw the body’s blood glucose levels out of balance because the body is unable to use glucose effectively. People with diabetes should pay special attention to carbohydrates.
It can be difficult to determine the quantity of carbohydrates in different foods and to decide which foods contain “healthy” carbohydrates. Manufacturers can use clever labeling lingo such as “net carbs,” “impact carbs,” or “effective carbs” to make you think that traditionally high-carb foods are actually low in carbohydrates. Are these “low-carb” foods worth buying? Is there a better way to choose carbohydrate foods?
Let’s start with the basics.
What are Carbohydrates?
When you consume foods and drinks that have carbohydrates, your body breaks these carbohydrates down into a type of sugar called glucose. Your body uses this glucose as its main energy source. Carbohydrates are an important part of a healthy and balanced diet, but not all carbohydrates are the same.
There are three types of carbohydrates: sugars, starches, and fiber. All three of these are included in the “Total Carbohydrate” line found on the Nutrition Facts label.
- Sugars are simple carbohydrates that are broken down easily and quickly by your body.
- Starches are complex carbohydrates that take longer for your body to digest.
- Fiber is a complex carbohydrate that cannot be broken down by our bodies. It is essential for glucose management, as well as heart and digestive health (American Diabetes Association [ADA], n.d.-c).
Understanding carbohydrates is particularly important for managing diabetes. Learning how to add and subtract carbohydrates in your meal plan will help you better manage your blood glucose and ultimately your health.
What are Net, Impact, and Effective Carbs?
The terms “net,” “impact,” and “effective” carbs are used interchangeably to describe the amount of carbohydrates found in a food after fiber and nonnutritive sweeteners are subtracted from the total carbohydrate number. For simplicity and clarity, we will call them net carbs in this article. Looking at net carbs is not an accurate way to determine the true carbohydrate content of foods.
The equation that food companies use to calculate “net carb” values is not accurate. It assumes that fiber and nonnutritive sweeteners provide no calories and do not impact blood sugar. This is not always true, and using these values can lead to unexpected effects on your blood glucose and inaccurate insulin dosing. A more helpful way to calculate your carbohydrate intake is to consider other parts of the food label, such as added sugars (ADA, n.d.-a).
What are Added Sugars?
Added sugars are those that are added to foods during processing. Sweeteners and sugars from honey, syrups, and concentrated fruit and vegetable juices are considered added sugars. Foods like sodas and baked goods often have high amounts of added sugar.
Consuming high amounts of added sugars can contribute to obesity and other health concerns. They can also make it more difficult to manage your blood glucose levels. Choosing to eat foods that have lower amounts of added sugars can help to manage your blood sugar and improve your overall health (Centers for Disease Control and Prevention, 2024).
How Do I Know Which Carbohydrate Foods to Choose?
Sometimes a food’s packaging can use marketing phrases that are confusing and may mislead consumers about how many carbohydrates are in a product. The best way to learn a food’s actual carbohydrate content is to read the Nutrition Facts label on the back of the package (ADA, n.d.-b). You can find the total amount of carbohydrate in each serving of the food by looking at “Total Carbohydrate.”
Beneath this line, you can find how much fiber is in the food by looking at “Dietary Fiber” (LeWine, 2024). Look at “Total Sugars” to check how much sugar is in the product and “Added Sugars” to determine how much of this sugar was added into the product during processing.
When managing your blood glucose, it can be helpful to remember two main things:
- total carbohydrate is the key information to look at on the Nutrition Facts label, and
- 15 g of total carbohydrate is considered one carbohydrate choice.
It’s best to choose carbohydrate foods that are minimally processed, high in fiber, low in fat, and contain low or no added sugars most of the time. Some examples are vegetables like green peas or corn, and whole grains like brown rice or whole wheat bread. Highly processed carbohydrate foods like enriched white breads, chips, and pastries have strong effects on your blood glucose, so you should limit these foods.
What are the Takeaways?
Ignore labels like “net carbs,” “impact carbs,” and “effective carbs” and look at the information on the Nutrition Facts label. “Low-carb” foods are not usually worth the money. When “low-carb” foods are compared to regular foods, they usually have about the same number of calories, as much or more fat, less taste, and are more expensive.
Instead, choose foods that are naturally lower in carbohydrates, such as lean proteins and nonstarchy vegetables, as the basis for your meals. These foods are nutrient-dense and naturally lower in added sugars, sodium, and saturated fat.
Remember that all nutrients listed on the Nutrition Facts label affect your health in some way. People all have their own health needs and may make different choices based on the information in the Nutrition Facts label.
If you have multiple medical conditions, you’ll need to take into account all of the information available to make the best choices for you. Speak with your healthcare provider or registered dietitian nutritionist if you need additional support to determine the best food choices for your individual needs.
References
American Diabetes Association. (n.d.-a). Diabetes & food: Get to know carbs. Retrieved August 26, 2025, from https://diabetes.org/food-nutrition/understanding-carbs/get-to-know-carbs
American Diabetes Association. (n.d.-b). Diabetes & food: Reading food labels. Retrieved August 26, 2025, from https://diabetes.org/food-nutrition/reading-food-labels/making-sense-food-labels
American Diabetes Association. (n.d.-c). Diabetes & food: Understanding carbs. Retrieved August 26, 2025, from https://diabetes.org/food-nutrition/understanding-carbs
Centers for Disease Control and Prevention. (2024, January 25). Nutrition. Get the facts: Added sugars. Retrieved August 26, 2025, from https://www.cdc.gov/nutrition/php/data-research/added-sugars.html
LeWine, H. E. (2024, February 5). Heart Health: Eat more fiber-rich foods to foster heart health. Harvard Health Medical School. Retrieved August 26, 2025, from https://www.health.harvard.edu/heart-health/eat-more-fiber-rich-foods-to-foster-heart-health
