Measuring Net Carbs for Weight Management

Medically reviewed by Karina Tolentino, RD

Tracking your carbohydrate intake is important if you have diabetes, are trying to lose weight, or follow a specialized diet like the ketogenic diet. But when it comes to the effect that carbs have on your body, focusing on your net carbs may be more applicable. Net carbs is equal to total grams of carbs minus grams of fiber and sugar alcohol.

Because fiber is not digested, it is believed that it does not have the same effect on the body as other carbohydrate grams. Therefore, net carbs is considered a more accurate number of carbs when calculating daily macronutrients.

This article will review the difference between total and net carbs and how to calculate net carbs.

First, How Are Net and Total Carbs Different?

Total carbs are the total amount of carbohydrate grams you consume in a day. You can find carbohydrate grams within food servings on nutrition labels, or estimates of carbohydrate amounts in foods like fruits and vegetables from online calorie counters.

Simple carbohydrates are digested quickly and increase your blood sugar rapidly, while complex carbohydrates are digested slower and raise blood sugar gradually.

Even though carbohydrate-rich foods can contain fiber, fiber cannot be digested and does not increase blood sugar. Because of this, fiber grams can be eliminated from your total carbs to determine your net carbs.  This is the amount of carbs that do have an impact on your blood sugar.

The amount of net carbs you consume in a day will differ from person to person depending on your sex, weight, activity levels, and health goals. Figuring out your daily macronutrient ratios can help you estimate your daily intake of net carbs.

Terms to Know

Simple carbs: fast digesting carbohydrates made of simple sugar molecules

Complex carbs: carbohydrates that contain longer chains of sugar molecules that are slower digesting

Refined carbs: complex carbohydrates that are processed to remove fiber and nutrients, turning them into simple carbohydrates

Read Next: How to Count Macros With a Set Health Goal

Calculating Net Carbs in Food

Net carbs in food are calculated by subtracting grams of carbs that cannot be digested. This mainly includes fiber, although sugar alcohols can also impact your net carbs.

What to Subtract

Net carbs are calculated by subtracting the amount of fiber grams you consume in a day from your total carbs. For example, if you consume food that has 20 grams of carbohydrates and 5 grams of fiber, you subtract 5 from 20 to get 15 net carbs.

Formula for Calculating Net Carbs

Total carbs (in grams) minus fiber (in grams) equals net carbs (in grams).

Learn More: How Fiber Helps Manage Diabetes

Factors to Consider

Sugar alcohols are compounds found within processed foods that taste sweet but have a different molecular structure from sugar. Sugar alcohols only partially increase blood sugar or do not increase blood sugar at all.

Examples of sugar alcohols include:

• Sorbitol

• Xylitol

• Mannitol

• Isomalt

• Maltitol

• Lactitol

Because sugar alcohols are hard for your body to digest, eating too many sugar alcohols can result in digestive issues like gas, cramping and diarrhea. Ideally, it is best to not consume sugar alcohols.

Why Do People Calculate Net Carbs?

For people with diabetes that are treated with insulin, it is important to have the most accurate carbohydrate count to better control your blood sugar. Calculating net carbs can help you understand the impact of the foods on blood sugar. Complex carbs that contain fiber are slower digesting than simple carbs and can help regulate your blood sugar more effectively.

Related: Simple Carbohydrates vs. Complex Carbohydrates

If you follow a low-carb or keto diet, your carbohydrate amount is limited, so calculating your net carbs can help determine a more accurate daily intake amount.

The keto diet generally restricts daily carb intake to less than 50 grams, so understanding the impact of fiber on total carb count can allow extra room in your diet to eat beyond 50 grams of carbs if carbs from fiber are subtracted.

Carbs and Blood Sugar

Consuming fiber and calculating net carbs isn’t the only way to reduce the impact of carbs on your blood sugar. Exercise, in addition to burning calories, stimulates muscles to pull in sugar molecules from the bloodstream for energy. This helps reduce blood sugar levels and can help manage diabetes.

Verdict on Net Carbs: Are They Worth Counting?

There is no official consensus about or legal definition of net carbs by the Food and Drug Administration (FDA), so net carb calculations may not always be accurate. If you have a condition like diabetes that requires strictly monitoring your carbohydrate count, it is best to work with a qualified healthcare professional to create a diet plan that works best for you.

Summary

Net carbs are calculated by subtracting grams of fiber from total grams of carbohydrates consumed in a day. Because fiber is not digested, it does not have an impact on blood sugar and is subtracted from total carbs to determine the amount of carbs that do have an impact on blood sugar.

Because they are difficult to digest, sugar alcohols may also have an impact on net carbs. There is no legal definition or parameters when calculating net carbs, so if you have to track carbs closely for medical reasons, it is best to work with a healthcare provider to monitor your diet.

Read the original article on Verywell Health.