A woman reading the nutrition label in a store

Net Carbs. What Are they and How Do You Calculate Them?

There’s no arguing net carbs are a hot topic. Some say the most accurate way to calculate your carb load is to consider your “net carbs” only. Although your body naturally loves them. Some say eat them. Some say avoid them. So what are you to do? If you want a slim waistline and would prefer living a long life free from disease, refined carbohydrates must go...or at least be reduced significantly. To get a more accurate representation of how the carbs you eat are affecting your weight, you should know the types of carbs to avoid, the number of carbs you should eat and when, and how to calculate net carbs.

What are Refined Carbohydrates?

Refined carbohydrates are typically grains and sugars that undergo extreme processing to remove almost all traces of nutrients. This includes vitamins, minerals, protein, fat, and fiber. Essentially, mostly what you’re left with is carbohydrates or “empty calories” as many call it. These foods quickly spike your blood sugar and insulin levels. And this is bad. Because chronic high blood sugar and insulin is what leads to weight gain, obesity, type 2 diabetes, and so on. So when it comes to carbs, we recommend getting them from whole food sources. And by this, I’m talking about colorful fruits and vegetables.

How Many Carbs Should You Eat?

The grams of carbs you eat per day also depends on your goals as well as your activity level and if you’re following a specific diet or way of eating. In our my personal and professional experience, a low carb paleo inspired or ketogenic diet is the best way to slim down and feel your best. Essentially, you want to condition your body to efficiently burn stored fat as fuel as opposed to carbs. And in order to do this, you need to feed your body more fat and fewer carbs. Thus, in these cases, determining the optimal grams of carbs that should be consumed daily is essential. Very generally speaking, ketogenic dieters typically consume no more than 35 - 50 grams of carbohydrates a day or 25 - 30 grams of “net carbs.”

What are Net Carbs?

The total amount of carbohydrates for any given food or product are broken down into several categories, which include:

  • Fiber
  • Starch
  • Sugars
  • Sugar alcohols

You’ll see some, if not all, of these on nutrition labels as well as in nutrient databases and apps, such as MyFitnessPal. However, not all categories of carbohydrates affect your blood sugar the same way. For instance, starches and sugars are rapidly absorbed and converted to glucose, which generally causes sharp spikes in your blood sugar and insulin. And as I previously mentioned, this is what you want to avoid.

On the other hand, fiber and sugar alcohols are slowly absorbed, if at all. Plus, they’re metabolized differently, if at all. Thus, they don’t cause your blood sugar and insulin levels to rise. Which is a good thing! Thus, the most accurate way to calculate your carb load is to consider only “net carbs” or the actual amount of carbs that will affect your blood sugar. Knowing the net carbs of specific foods will allow you to determine appropriate serving sizes in order to stay within your limit. Let’s look at a few examples:

Raspberries: raspberries are an excellent source of antioxidants as well as fiber. A half-cup serving contains approximately 7 grams of carbohydrates. However, 4 grams of this total comes from dietary fiber. Thus, the calculation for net carbs would be as follows: 7 grams (total carbs) - 4 grams (dietary fiber) = 3 grams (net carbs)

Spinach: spinach is packed with vitamins, minerals, and powerful plant nutrients to keep you healthy and slim. We  I love adding a handful in our my collagen shakes. And fortunately, most of the carbs (64%) come from fiber. Thus, low carb dieters can get away with eating lots of spinach as well as most other leafy greens. The exact net carb count for one cup of spinach is as follows: 6.75 grams (total carbs) - 4.32 grams (dietary fiber) = 2.43 grams (net carbs)

Avocado: avocado is one of our my favorite superfoods. It’s got it all. Healthy fat, vitamins, minerals, phytonutrients, and good dose of fiber. It’s a delicious and filling the perfect food for low carb and keto diets. Plus, it’s creamy and delicious! Let’s take a look at the math for a half-cup serving: 6.4 grams (total carbs) - 5 grams (dietary fiber) = 1.4 grams (net carbs)

How Does the Body Digest Fiber?

Fiber is a type of carbohydrate that our bodies can't digest. It moves through our digestive system mostly unchanged, and this is what contributes to its many health benefits. There are two types of fiber: soluble and insoluble. 

  • Soluble fiber dissolves in water and forms a gel-like substance, which can help lower blood glucose levels and cholesterol. 
  • Insoluble fiberpromotes the movement of material through your digestive system and adds bulk to the stool, aiding in regular bowel movements.

The process begins in the stomach, where food is mixed with stomach acid and enzymes. Fiber, however, remains largely undigested at this point. It moves into the small intestine, where other types of carbohydrates, like sugars and starches, are broken down and absorbed — but fiber continues its journey relatively intact.

Upon reaching the large intestine or colon, soluble fiber undergoes fermentation by gut bacteria. This process produces short-chain fatty acids and gasses, which may lead to bloating in some individuals. These short-chain fatty acids provide numerous health benefits, including supporting gut health and encouraging insulin sensitivity.

It's essential to check food labels for fiber content when planning your meals. The FDA recommends a daily intake of 25 grams of fiber for a 2,000-calorie diet. However, needs may vary based on age, gender, and health goals, and it's always a good idea to consult with a dietitian to determine what's best for you.

How Does the Body Digest Sugar Alcohol Carbs?

Sugar alcohols are types of sweeteners found in many sugar-free and low-carb foods. They are a popular choice for those seeking weight loss or blood glucose control, as they have a lower glycemic index than regular sugar — this means they generally shouldn’t raise your blood sugar as much. Common sugar alcohols include erythritol, xylitol, sorbitol, and maltitol.

The digestion of sugar alcohol begins in the small intestine. Unlike sugars and starches, they are not fully absorbed into the bloodstream. This results in a slower and smaller impact on blood sugar levels compared to regular sugars.

However, because they are not fully absorbed, sugar alcohols continue their journey to the large intestine. Here, they are fermented by gut bacteria. This process can sometimes cause digestive discomfort, like bloating, especially when consumed in large quantities.

Sugar alcohols can be subtracted from total carbohydrates when calculating net carbs, just like fiber. But be sure to check food labels and the ingredients list, as food manufacturers have different ways of listing these sweeteners. Atkins and other low-carb diet followers often use these types of carbohydrates as part of their eating plan.

Just remember, everyone's body responds differently to these types of carbs, so it's important to observe your own reactions and adjust accordingly. Your dietitian or healthcare provider can provide personalized advice based on your wellness goals.

Spacing Out Your Carbs

If you’re following a low carb diet, we , I also recommend spacing out your carbs. For instance, if your daily limit is 30 grams of net carbs, then you probably shouldn’t have them all in one meal. Maybe loosely target 10 grams per meal if you eat 3 meals a day and 15 grams per meal if you are an intermittent faster and only eat 2 meals a day. This will ensure your carb load during any given meal stays low as well as avoid a blood sugar spike.

How Does Fiber Affect Carb Metabolism?

Fiber has a unique impacton carb metabolism. Unlike simple carbs that are quickly broken down into sugars and absorbed into the bloodstream, causing a rapid rise in blood glucose, fiber is a complex carb that the body handles differently.

When we consume fiber-rich foods like whole grains and veggies, the body is unable to fully break them down. This slows the absorption of other carbs eaten at the same time, which can help manage blood sugar spikes. 

So even though fiber is a part of the total carb count listed in nutrition facts, its non-digestibility means it does not contribute to blood sugar levels in the same way as other carbs.

What Are the Benefits of Counting Net Carbs?

While some people prefer not to count carbs, many people who follow a keto diet do choose to count their carbs. This is because it can help them stay in ketosis and be mindful of how they’re eating. Here are a few reasons why you may want to consider counting your net carbs.

1. Less Restrictive

Counting net carbs instead of total carbs can make a low-carb or ketogenic diet more accessible. By subtracting grams of fiber and sugar alcohols, like mannitol, from the total carb count, we get the net carbohydrates. This method allows the inclusion of more nutrient-dense foods, such as veggies and certain protein bars, without significantly increasing blood sugar.

2. May Encourage a Higher Intake of Fiber

Because fiber can be subtracted from the total carb count when calculating net carbs, people may be more inclined to consume fiber-rich foods like whole grains and veggies. These foods, apart from their fiber content, are packed with vitamins, minerals, and antioxidants that contribute to overall health.

3. May Support Balanced Blood Sugar Levels

By focusing on net carbs, individuals can better regulate their blood sugar levels. Net carbs account for the carbs that affect blood glucose, allowing for more precise dietary planning and better blood sugar control.

collagen fiber bar

What Are the Downsides of Counting Net Carbs?

Although there are many benefits to counting net carbs, there are plenty of people who prefer not to. Here are a few reasons why some people may not be interested in counting net carbs.

1. May Be Less Effective for Those With Health Conditions

While counting net carbs can be beneficial for many, it might not be the best approach for everyone. Individuals with specific health conditions, such as diabetes or metabolic syndrome, might need to pay more careful attention to their total carb intake, including fiber and sugar alcohol.

2. Not 100 Percent Accurate

Counting net carbs is not a foolproof method. The Food and Drug Administration (FDA) does not regulate the term "net carbs,” and manufacturers may calculate them differently. 

Also, not all sugar alcohols have the same effect on blood sugar, and the fiber in packaged foods can vary in quality. Thus, relying solely on net carbs without considering other aspects of nutrition can be misleading.

How To Calculate Carbs When Using Whole Foods

When calculating carbs in whole foods, it's important to consider both total carbohydrates and net carbohydrates. To determine the total carb count, make sure you reference a reliable nutrition database, which will provide you with an accurate grams-per-serving measurement for the food in question.

To find the net carb count, subtract the grams of fiber from the total carbs. For example, if a cup of broccoli contains six grams of total carbs and two grams of fiber, the net carbs would be four grams (sox grams total carbs - two grams fiber).

What Are High-Carb Whole Foods?

Certain whole foods are high in carbs. These include starchy vegetables like potatoes and corn, fruits like bananas and apples, and grains like rice and oats. 

While these foods are rich in carbs, they also provide important nutrients and can be part of a balanced diet when consumed in appropriate portions.

How To Calculate Carbs When Eating Processed Foods

When dealing with processed foods, calculating carbs can be a little more complex due to the inclusion of added sugars and sugar alcohols. However, food labels can be incredibly helpful in this case. 

Look at the nutrition facts panel to find the total carbohydrates. This number includes all types of carbs: sugars, fiber, and sugar alcohols.

To calculate net carbs in processed foods, subtract the fiber and the grams of sugar alcohols from the total carbs. It’s important to note that not all sugar alcoholsimpact blood sugar equally. 

For instance, erythritol doesn’t affect blood sugar, while others, like maltitol, may have a minor impact. Make sure to consider this when calculating net carbs in processed foods.

What Are High-Carb Processed Foods?

Many processed foods are high in carbs, particularly those with added sugars. These include sweets like cookies, candies, and cakes, as well as many breads, pastas, cereals, and snack foods. Soft drinks and fruit juices are also high in carbs.

Processed foods can cause rapid spikes in blood sugar and may contribute to health problems over time. Therefore, it's essential to read food labels carefully and pay attention to both the total and net carbs.

How Can You Eat a Low-Carb Diet?

Eating a low-carb diet involves choosing foods that have fewer total and net carbs. 

Start by focusing on whole foods, particularly lean proteins and non-starchy vegetables. Fish, poultry, eggs, leafy greens, and cruciferous vegetables are all excellent low-carb choices. Nuts and seeds can also be included in moderate amounts.

When it comes to processed foods, you may want to choose those with no added sugars and a low net carb count. Reading food labels can help you make informed choices about the foods you consume.

In Conclusion

Calculating net carbs is a more accurate representation of carbohydrate intake when it comes to how carbs affect your blood sugar and insulin levels. Because fiber, a component of carbohydrates, is not your enemy. Thus, if you’re battling with a blood sugar disorder, it’s always a good idea to calculate your net carbs. Plus, if you’re on a low carb diet hoping to turn your body into a fat-burning machine, calculating your net carb intake is essential.

Keep thinking Big and living BOLD!


Fiber | The Nutrition Source | Harvard School of Public Health

Questions and Answers on Dietary Fiber | FDA

What You Should Know About Sugar Alcohols | Cleveland Clinic

Effects of Dietary Fiber and Its Components on Metabolic Health | PMC

The Role of Short-Chain Fatty Acids | NCBI Bookshelf

How Does The Stomach Work? | NCBI Bookshelf