If you’ve ever looked at the carbs on our packaging, you might have been a little confused. On our Goes Hawaiian and Raspberry Dream bars, for example, the total carbs listed in the nutrition facts aren’t the same number as the net carbs we list on the front.
What’s up with that? It all comes down to calculating net carbs. To clear things up, we thought we’d offer a quick explainer on what net carbs are and how to calculate them.
The scoop on net carbs
Not all carbohydrates are created equal. Your body can break down some carbs into glucose, fueling your cells but also raising your blood sugar levels. Other carbs, like fiber, don’t get broken down into glucose.
When you’re trying to calculate how many carbs your body is absorbing (net carbs), you need to subtract the carbs your body can’t fully digest from the total carbs.
With whole foods, that calculation is usually as simple as subtracting the fiber from the total carbs. Let’s take an apple as an example. An apple has 25 grams of carbs, but about 4.5 of them are fiber. Do some quick math to find that an apple has 20.5 grams of net carbs.
When you move away from whole foods, calculations get a little bit more complicated. That’s because a lot of foods contain sugar alcohols, which your small intestine can only partially absorb. When a food has sugar alcohols in it, you need to know how much of those sugar alcohols your body can digest to calculate net carbs.
With most sugar alcohols, it’s a safe bet to assume your body can digest half of them. So to calculate net carbs, take total carbs, then subtract all the grams of fiber and half of the grams of sugar alcohols.
But there’s one key exception.
Erythritol: our key to low net carbs
Erythritol is a sugar alcohol you get from fermenting the glucose in wheat starch or corn. The result is an extremely low-calorie sweetener.
But unlike other low-cal sugar alcohols, your body absorbs the vast majority (90%) of erythritol in your small intestine, then immediately gets rid of it in your urine. Your body ferments the remaining 10% in your colon, turning them to short-chain fatty acids.
That means erythritol doesn’t raise your blood sugar or cause any of the tummy troubles that can come with other sugar alcohols. And it means none of the carbs in erythritol count toward your net carbs.
In fact, you can subtract every gram of erythritol from your net carbs. Let’s do the math on a couple of examples:
Our Goes Hawaiian bars have 14 grams of total carbs. 3 of those are dietary fiber and 8 of those are erythritol
14 g of total carbs - 3 grams of fiber - 8 grams of erythritol = 3 net carbs
Our Raspberry Dream bars have 15 grams of total carbs. 3 of those are dietary fiber and 8 are erythritol.
15 g of total carbs - 3 grams of fiber - 8 grams of erythritol = 4 net carbs
Why net carbs matter
So, why all this math? Knowing your net carbs clues you into how many carbs your body will digest into glucose, affecting your blood sugar. More blood sugar means more insulin, the hormone your body uses to turn glucose into energy for your cells.
If you’re trying to minimize your insulin response (for example, if you’re trying to reach ketosis on the Keto diet), net carbs matter.
Whatever your reason for calculating net carbs, we hope this guide helped you!