Walking through my local grocery store last week, I passed by the aisle with protein bars, granola, and generally healthy-ish snacks, and something caught my attention—a giant “keto-friendly” cookie that proudly proclaimed it had just 3 grams of net carbs on the front of the package. Cool, I thought, I like cookies and I’d rather not jack up my blood sugar.
But flipping over the package revealed that this seemingly innocent cookie had 26 grams of total carbs. What gives?
According to the company, most of those carbs come from allulose—a type of sugar alcohol—which means it basically “doesn’t count,” as your body can’t metabolize it like regular sugar, and some of those carbs come from fiber, which isn’t absorbed, so that “doesn’t count” either. At least that’s what several companies marketing their products to low-carb, keto dieters are claiming. But honestly, it seems too good to be true.
Here, we asked some nutrition experts for their thoughts on net carbs, whether it ever makes sense to count them (as opposed to total carbs), and what might be more important to focus your attention on while sticking to a low-carb diet.
What are net carbs (and how do you calculate them)?
“Net carbs,” sometimes referred to as “impact carbs” or “active carbs,” isn’t a legally defined term. The only type of carb regulated by the Food & Drug Administration is the total carbs you see on the nutrition facts, which is broken down into dietary fibers and sugar.
So, depending on who you ask, you might get a slightly different definition on how net carbs are actually calculated. But here’s the general consensus:
- When you’re looking at whole foods: net carbs = total carbs – fiber
- When you’re looking at packaged foods: net carbs = total carbs – fiber and sugar alcohols
But what’s the point of this calculation? The basic concept is that not all carbs are equally absorbed by the body—and thus, they shouldn’t be counted. These uncounted carbs are sometimes referred to as “non-impact carbs” or “inactive carbs.”
