Should I Count Carbs or Net Carbs To Lose Weight, and How Do I Calculate Them?

  • Medical Reviewer: Mahammad Juber, MD
Medically Reviewed on 11/21/2022
Cutting carbs by limiting low-quality carbs can prevent some of the leading health conditions in the United States and help you feel better overall.
Cutting carbs by limiting low-quality carbs can prevent some of the leading health conditions in the United States and help you feel better overall.

Low-carb, net-carb, zero-carb, counting carbs—manipulating carbohydrate intake is at the heart of many diets. Getting lost in the weeds is easy, but carbs don’t need to be complicated.

About carbohydrates

The popularity of low-carb diets seems to have led some to villainize carbohydrates, but they’re a vital part of a healthy diet. You should focus more on the quality of the carb than the quantity.

What is a carbohydrate? 

A carbohydrate is a macronutrient made of glucose, which gives your body energy. The most common types of carbohydrates are:

  • Sugars
  • Starches
  • Fibers

Along with fats and protein, carbohydrates make up the calories in your food. Cutting carbs is a deliberate form of cutting calories. 

About sugars

Sugar can be naturally occurring in fruit or added as corn syrup in many foods. Unfortunately, most sugary foods are carb-dense and lacking in nutrients.

About starches

Grains, some vegetables, and legumes contain starch. Some foods, like potatoes or refined grains, have even more starch and can quickly eat up your carb budget.

About fiber

Fiber is a powerful, nondigestible carbohydrate often found in whole grains, fruits, and vegetables.

Carbs: quality vs. quantity

Carbs are energy, which equates to calories. The more carbs you eat, the more calories you ingest. Cutting carbs by limiting low-quality carbs can prevent some of the leading health conditions in the United States and help you feel better overall.

What is a low-quality carb? 

Sugars and starches cause the most problems for those who should be counting carbs. Foods with many sugars or starches are often low in necessary nutrients and can therefore be considered a “low-quality” carb. 

For example, a glass of orange juice and an orange both have sugar, but a glass of juice has a lot more sugar and less fiber. As another example, most of the calories in potatoes come from starch, but mashed cauliflower has many of the same benefits as mashed potatoes with much less starch. 

Fiber is a high-quality carb

Fiber has incredible benefits. It’s a complex carbohydrate, so it passes more slowly through the digestive system and:

  • Prevents  spikes in blood sugar
  • Helps you feel full longer
  • Promotes healthier bowel movements

Fiber plays a unique role in carb counting, including the calculation of net carbs. 


The Best Diet Tips: How to Lose Weight the Healthy Way See Slideshow

What are net carbs?

Net carbs are the total amount of carbs in a food minus the amount of fiber. Not counting fiber in your total carbs is a contentious subject, though. 

Insoluble vs. soluble fiber 

Soluble fiber dissolves in water and is absorbed by your body. These fibers “count” as part of your daily carbs.

Insoluble fiber doesn’t dissolve in water and passes through your body undigested. Since the energy and calories from the fiber aren’t absorbed, they “don’t count”.

Fiber is fiber

If you are counting carbs, fiber is the least of your worries. The differences between insoluble and soluble fibers are negligible in the face of starches and sugars. 

All fiber is beneficial. Structuring your diet with various high-fiber foods will guarantee the benefits.

Counting carbs vs. counting net carbs

Since determining net carbs means subtracting fiber from your daily carb intake, you’re really just counting starch and sugar. 

If your goal is to lose weight, counting net carbs can give you a better idea of what’s in your food. It encourages you to look closely at the carbohydrates you’re eating, specifically in terms of sugars and starches. 

Counting carbs and weight loss

Carbs play a significant role in your diet. In fact, carbohydrates should make up about 45% to 65% of the calories you eat daily.

You can measure carbs in grams, and each gram of carbs will provide about 4 calories to your body. Fiber breaks this rule, though, since most of it isn’t absorbed.

Foods with starch or sugar often have many carbs compared to high-fiber foods, so if you’re restricting the number of calories you eat, you won’t be able to eat as many starches and sugars. 

Whatever your diet looks like, more fiber, fewer starches, and fewer sugars are generally a good idea. 

Counting carbs

The first step to counting carbs is to take a step back and examine what you typically eat. Don’t worry about changing your eating habits at first.

Read the labels

Take time to read the Nutrition Facts label on the foods you eat and start tracking the carbs. You can keep a physical diet journal or record the carbs using a carb-counting or diet app.

The Nutrition Facts label will have a few statistics listed that are important to counting carbs:

  • Serving size
  • Total carbohydrates
  • Dietary fiber
  • Total sugars

Calculate the carbs

Look at the total carbohydrates stat in grams, then subtract the fiber and total sugars. The remainder is the amount of starch. Once you’ve done that, you have the number of grams for each carbohydrate. 

Track your carbs for a week or so to get an idea of your typical eating habits. This will give you a starting point to create your goals. 

Make substitutions

Instead of slashing your carb intake, replace starches and sugar with fiber. For example, if you eat a lot of starchy vegetables like corn, replace your corn with a green vegetable. If you eat a lot of refined grains like white bread, switch to whole-grain bread. 

Added sugar pops up in unlikely places, but an easy way to avoid excessive added sugar is to replace highly processed sweets with fruit. A few pieces of dried fruit can satisfy your sweet tooth and give you an extra fruit serving.

Should you count carbs?

Counting carbs is one approach to balancing your diet. It’s a great way to manage blood sugar and prevent diabetes, but it can also create a healthy challenge for people who need to diversify their diet.

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Medically Reviewed on 11/21/2022
Centers for Disease Control and Prevention: "Carb Choices," "Carb Counting," "Food Labels." "Do Fibers Count as Calories and Carbohydrates?"

Harvard T.H. Chan School of Public Health: "Carbohydrates," "Fiber."

National Academies of Sciences, Engineering, and Medicine.: "Dietary Reference Intakes: Proposed Definition of Dietary Fiber."

U.S. Department of Agriculture: " Dietary Guidelines for Americans, 2020-2025."