Net Carbs, Who’s Counting?

The breakdown of carbohydrates

Carbohydrates are the main source of energy in most diets. When you eat and digest carbohydrates, they are converted into glucose, which fuels the body and brain, and gives you energy. Food contains three main types of carbohydrates: sugar, starches and fiber (1). Depending on the structure of the carbohydrate and how it affects blood sugar, carbohydrates can be classified as either simple or complex.

Simple carbohydrates are broken down more quickly and send quick bursts of energy (as glucose) into the bloodstream, followed usually by a crash of fatigue when the sugar is depleted (1). There are two types of sugars; those that are naturally occurring and those that are refined or processed. Naturally occurring sugars usually also come with vitamins, minerals, and fiber that our bodies need, like those in fruits and milk. Refined sugars are those that are found in soft drinks, candy and baked goods. They can provide calories, but often lack vitamins, minerals and fiber and can lead to excessive energy intake (1).

Complex carbohydrates are referred to as such because they are broken down slower in the body, supplying a slow and steady supply of energy (as glucose) into the bloodstream (1). Complex carbohydrates are usually made up of unrefined starches and fiber. Food rich in complex carbohydrates also provides many essential nutrients and the fiber helps your digestive system work well. Foods such as beans, lentils, oats, rice, and whole grains are examples of complex carbohydrates. 

Total carbs vs. net carbs

In the U.S., total carbohydrates are listed on the nutrition facts panel, followed by a breakdown of the amount of dietary fiber, sugars, added sugar and sugar alcohols (if applicable) in the food. The term "total carbohydrate" includes all three types of carbohydrates: sugars, starches and fiber (2). 

Net carbohydrates are meant to reflect the grams of digestible carbohydrates in a food that can significantly impact your blood sugar level, i.e. sugars and starches. While they are not listed on the nutrition facts panel, net carbs can be calculated based on the following equation:

Total carbs – fiber – other non-digestible carbs (if applicable) = Net Carbs (3)

Fiber and other non-digestible carbs (such as sugar alcohols) are not “counted” because they do not significantly impact blood sugar, and are supposedly less likely to interfere with weight loss.

However, different countries have different rules on food labeling. This equation only works for the U.S. because the total grams of carbohydrates includes all types of carbohydrates for each food including fiber, with fiber also listed separately. In Europe and Australia, food labeling regulations differ, and the total carbohydrates number on labels from these countries represents digestible carbs only. The fiber count is still listed separately, but has already been excluded from the total carb number. In short, there is no need to subtract fiber from total carbs because the label has already done it for you.

Net carbs and the low carb diet

Since sugars and starches can impact blood sugar levels while fiber does not, it is believed that net carbs interfere most with weight loss. Fiber also contributes to digestive health, helps to keep you regular, and helps to make you feel full and satisfied after eating, which can contribute to weight loss. So where do net carbs fit into a low carb diet? Extremely low carb diets limit your carbohydrate intake- often to 50 grams or less per day- leaving less room for nutrient-rich carbohydrate foods such as fruits, vegetables, beans and whole grains. Tracking net carbs enable you to incorporate more fruits, vegetables and grains into your diet plan without exceeding your carb limit. Nutrition tools such as Lifesum can help you track your carbs so that you know you are staying within the right range. Lifesum’s keto diet feature is tailored specifically for those looking to start a low carb diet, and provides a carb-tracker tool that includes net carbs, ketogenic recipes for all occasions and advice on how to keep you going.

While counting net carbs is not a fool proof equation, it has been suggested to be beneficial in promoting weight loss in low carb diets such as the keto diet. It is important to remember that because each person’s body reacts differently and can have different outcomes to the same diet, you should make sure that you receive the proper information on how to count net carbs safely and healthily. This can help you follow the diet properly while still getting all of the essential nutrients your body needs. How do net carbs fit into your diet goals?