Simple Guide on How To Calculate Net Carbs

How to Calculate Net Carbs

This is a quick and easy article to answer a question I get ALL the time… HOW to figure out how many net carbs are in any food, drink, recipe, etc. and WHY they influence if and when we lose or gain weight.

The Short Answer:

My standard and the short answer anytime I am asked this question is “Total Carbs MINUS Total Fiber MINUS Alcohol (NOT regular) Sugars when eating sweets = Net Carbs that can be absorbed by your body. “

Calculating net carbs for Atkins Bars

The Long Answer:

The whole premise of calculating net carbs is based on the principle that not all carbohydrates affect the body the same way.

Some carbs, like starches and sugars, are absorbed rapidly, causing blood sugar levels to quickly rise after eating. Those excess carbs are stored in the body as fat. Examples of these types of carbs include potatoes, wheat-based breads, rice, and sweets laden with sugar.

Fiber on the other hand moves slowly through the digestive system, and much isn’t digested at all.  This fiber is referred to as being insoluble. Since it is insoluble it isn’t going to impact your weight, so you can subtract fiber from total carbs to calculate net carbs; those that will be absorbed and hinder your weight loss.

Also in the category of largely indigestible carbs are sugar alcohols. You will find them listed as mannitol, sorbitol, xylitol, and other polyols. These substances are commonly used as artificial sweeteners and usually (notice the word largely) do not influence weight gain. I say usually because they tend to stall some people’s weight loss, but you will only know if you fall within that category if you pay attention and monitor your body’s “reaction” to them when consumed. If you find that your weight plateaus after the introduction to sugar-free candies, ice cream, sodas or other such treats it’s best to curb the amount you ingest. 

So for the Atkins’ Bars referenced in the nutritional label above you would pay attention to the area outlined in red.  The bars start out at a total of 22 carbohydrates.  Out of those carbs 10 are fiber and 10 are alcohol (not regular) sugars so you can subtract those. That leaves you with 2 net carbs per serving or bar. Notice that you do not and cannot subtract any sugars not identified as an alcohol because those are going to be immediately absorbed by your body and yes, those will definitely influence weight gain. These are so small in number that they will not factor into the equation.  If there are no sugar alcohols (anything that isn’t sweet) then you just subtract fiber for your net carb count.

People also ask me all the time, so what about fruit? For the complete answer check out my article on low carb fruit.  Carbs are carbs. Note that natural sugars will make you gain weight just as easily those stored in your pantry as granulated sugar.

Calculating carbs in a banana

In the case of a medium banana you again are going to pay attention to the area in red in the image above. One medium banana has 27, yes count them, 27 total carbs! You CAN deduct the 3 grams of fiber but that still leaves a whopping 24 net carbs your body will absorb! That’s more than most people on the Atkins diet eat in a whole day! As you can see 14 of those 24 carbs come from sugar, plain old turn to fat in your body sugar!  

On the other hand if you want to eat fruit (and you’ll find all this broken down for you in the low carb fruit article mentioned above) try berries. 

How to calculate net carbs in strawberries

As you can quickly see you can eat a whole pint of strawberries and you haven’t reached as many carbs as in that one medium banana! 27 total carbs minus 7 grams of fiber leaves you with 20 net carbs. Now yes, that is what we recommend in the Low Carb Challenge and on the Atkins way of eating for a full day but most people will not eat a full pint of strawberries, it just makes my point. I for one dice one, maybe two strawberries over my low-carb yogurt, ice cream, muffin in a minute, cheesecake, etc. I just want the flavor, not the carbs.  

Now we’ll take a look at one more type of food that doesn’t involve what we traditionally think of as sweets. Would you be surprised to learn that zucchini has sugar? Yes, sugar. 

calculating net carbs in zucchini

But as you can also see you can have a full medium-size zucchini for only 4 net carbs! That’s why zoodles are so popular! Note that those carbs come almost exclusively from sugars.  I tell you those carbs hide in the most ingenious places!  

So that’s the skinny on calculating net carbs.  In the end it all boils down to “Total Carbs MINUS Total Fiber MINUS Alcohol (NOT regular) Sugars when eating sweets = Net Carbs that can be absorbed by your body.”  If you just remember that you’ll do fine.

As always I value your thoughts and ideas and invite you to leave them in your comment below or over on our Facebook group or page and if you learned anything new, found this article interesting or helpful please give it a big thumbs up by sharing it with your friends!
In the meantime, ciao for now!

Ciao for NOW! ~Marge Burkell

*articles may contain affiliate links to help feed my blogging habit and family*


Please be advised. the information that is shared herein is intended for informational purposes. Any advice and/or product(s) mentioned should not be used to diagnose, treat, cure, or prevent any disease.

Always consult your healthcare professional if you are currently taking medication, pregnant, trying to get pregnant, nursing, or if you have any other health condition before taking any products mentioned or applying any information contained herein.

So... what's YOUR take on this?