by Grace Rivers, RDN, CDCES
You have seen food packages that boast net carbs, but what does it mean? To date, there isn’t a formal definition from the US Food and Drug Administration (FDA) for the term net carbs, but it continues to be used by food companies to make a food seem more appealing.
What is a net carb?
The net carbs are derived by taking the total carbohydrate amount and subtracting the fiber and sugar alcohol sweeteners from the total carbs. The belief is that if you follow the net carbs, you can eat more of that particular food without it causing any rise in your blood sugar or insulin response. That may work, and it may not.
If food is a carbohydrate, it will impact your blood sugar level. Even though it contains fiber, not all fiber affects your blood sugar the same. Insoluble fiber travels through your gut intact, but some of the soluble fiber is fermented in your lower intestine. Fiber can help improve satiety, slow the rise in blood sugar, and lower cholesterol levels.
Another type of fiber is those that are processed. They are not naturally occurring in foods. Instead, they are added to processed foods and don’t show the same value as the other two intact fiber types. If it is processed, you may not receive the same health benefits.
What about sugar alcohols?
Despite the name of sugar alcohols, they aren’t sugar or alcohol. They are, however, a carbohydrate. Sugar alcohols impact your blood sugar slower than regular sweeteners, so they can help prevent sugar spikes. However, eating more of the product can impact your blood sugar and your gut.
You may recall a few of these from food labels:
Sorbitol
Mannitol
Xylitol
Isomalt
Maltitol
Erythritol
You don’t completely absorb sugar alcohols, but they provide two calories in each gram compared to four calories in a gram of sugar. So, a better bet may be only to remove half of them when subtracting from total carbs.
The exceptions are erythritol, which only supplies about 0.2 calories in each gram, and allulose at 0.4 calories a gram.
How well does your gut tolerate these sweeteners?
Excessive amounts of sugar alcohols can have a laxative effect on your gut since they cause water to go into your large intestine that can lead to an increase in bowel movements, bloating, or diarrhea.
Erythritol shows the smallest indication of stomach upset, but one study showed that large amounts of the sweetener could cause issues.
Controlling the amount of added sugars
To help decrease the number of added sugars in products and on labels, food companies use sugar alcohols instead of any sweetener that would count as an added sugar, such as honey, cane sugar, or corn syrup.
You will also see sweeteners in food products like sucralose, stevia, or aspartame. These don’t have calories nor do they have an effect on your blood sugar.
Making the best choices
Net carbs aren’t as easy as subtracting all fiber and sugar alcohols.
Make sure you choose an ideal product for you. If you decide to follow net carb guidance from a food label, notice how you tolerate them and if they help you reach your blood sugar goals.
If you are thinking about purchasing a product that contains net carbs, compare it to the regular product by the same company. It could be the calories, total carb, or saturated fat content are equal or higher. And be sure you like the taste and texture of the net carb food choice.
You often eat more than one food at once, so check your blood sugar a few times after counting net carbs to determine how well they work for you.
