What is the Difference Between Carbs and Net Carbs? How to Calculate Net Carbs On A Low-Carb Diet

If there is anything worth counting, it’s carbs. Limiting carb intake maximizes fat-burning and helps to regulate blood sugar and insulin levels. But not all carbs are created equal.

The principal problem with many low-carb diet plans is that they unfairly vilify foods that seem high in carbs (such as vegetables) but are, in fact, NOT high in digestible (net) carbs.

So what is the difference between total carbs and net carbs?

There are basically two types of carbs – those which your body can digest and those it cannot. The type it can’t digest is principally fiber.

In America, food labels include fiber in the total carb count which gives an inaccurate measure of the food’s effect on your waistline. So most-low carb diets ask that you count “net carbs” – the ones that are actually digested.

The total carbohydrate number is not important. It is NET carbs that really matter since those are the ones that are being digested. Count your NET carbs, not your total carbs.

Non-fiber carbs = fattening
Fiber carbs = not fattening (and actually filling as well as beneficial for digestion and fat burning)

To calculate net carbs, simply subtract the dietary fiber content from the total carbs. In the picture to the right, the net carbs would be 15 – 5 = 10.

Carbs – Fiber = Net Carbs

Simple enough, right?

Well… not so fast. Here comes corporate trickery once again.

Beware of Low-Carb Products!

Eager to make a quick buck on low-carb bars, shakes, and candies, many companies have rushed to create products that have misleading labels that appear low-carb diet friendly. Unfortunately, many of these products are artificially sweetened with sugar alcohols like malitol, sorbitol, and lacitol which can be metabolized into sugar.

Sloppy labeling laws allow companies to include these sugar alcohols on the labels as FIBER even though they clearly are not.

I’ll get into the evils of sugar alcohols in an upcoming post, so stay tuned. For now, count your net carbs and steer clear of low-carb products. If you do eat anything with sugar alcohols, your best bet is to count them all since you really can’t believe the label.

In short, trust vegetables, not low-carb candies.




Share this with your friends!

You might also be interested in:


  1. Agreed. That formula does not work correctly for the Atkins meal bars. I do not see why Atkins would try and “trick” someone on their program.

  2. So is it good to have a high number or low number of net carbs? For example, Quest Bars advertise being low carb, but they have 21 grams of total carbs, 17 grams grams of dietary fiber, and 4 grams of net carbs. So are they really “low carb?”

    Thanks for your help

  3. Soluble fiber is actually digested in the colon and re-absorbed back into the body as short chain fatty acids, so you’re still getting around 60-70% of the calories from fiber. Only insoluble fiber passes through unabsorbed, and this only accounts for a few grams at the most.

  4. I thank you for this information. It was very helpful. I have been eating low carb for almost one year and have lost sixty pounds. I feel much better, have more energy and my overall health has improved.

  5. Are quest bars considered mislabeled becsusevof the sugar alcohols included? Are all sugar substitutes included in spiking blood sugar levels ?

  6. I was under the impression that low carb diets such as Atkins diet is the quickest way to lose weight because phase 1 only allows 20 net carbs per day which puts your body into ketosis and cuts cravings , although is very constipating & does cause bad breathe. , this doesn’t include fiber. Doesn’t fiver such as fruit and vegetables defeat the purpose if added to this type of low carb diet ? The drawback is that it’s constipating but the idea that it cuts craving helps make it work. What is your opinion ?

Leave a Reply


You may use these HTML tags and attributes:
