Food Products Are Touting Low Numbers of ‘Net Carbs’. What Does That Even Mean?

ON A REGULAR Tuesday, I picked up a package of tortillas for taco night. I had unintentionally grabbed a brand that’s low-carb—a happy accident, I thought, as I’d already had a carb-heavy day of eating.

After eating my one “appetizer” tortilla (you know exactly what I’m talking about), I had my two tacos. I noticed something as I was putting the tortilla package back in the cupboard—an equation.

19 Grams Total Carbs – 17 Grams Total Fiber=2 Grams Net Carbs

That’s the moment I learned a single one of these tortillas had 17 grams of fiber (I had three). Add that up with the fiber I’d already consumed from the rest of my eating that day, and I’d had about 71 grams of fiber.

Do you know how many grams of fiber you’re supposed to have in a day? Between 30 and 38 grams. You know what happens when you have too much fiber? Diarrhea or constipation.

While I’ll spare you the details of what happened after that, it left me to wonder—was I actually getting less carbs in those tortillas because they were so high in fiber?

I asked the experts.

What does ‘net carb’ mean?

“Net carbs refers to the amount of digestible—what the body uses as a source of energy—carbohydrates in a food,” says Leslie Bonci, R.D., sports dietitian for the Kansas City Chiefs.
Fiber is not entirely digested by the body. So, the equation for net carbs is total carbs minus total fiber.

Do you really consume less calories from carbs when you eat something high in fiber, though?

Kind of.

“A food that is high in fiber is not calorie free,” Bonci says. “We do absorb some of the calories from high fiber foods so it is misleading to subtract all the carbs from fiber in a product.”

And, if you’re on the Keto diet, those few extra carbs could prevent you from achieving ketosis.

It’s important to note that the FDA does not recognize net carbs as a legit food labeling tool. “There is no legal definition. It is a marketing term,” Bonci says.

It’s often used when companies are trying to get low-carb or Keto eaters to buy their products. That’s why you’ll typically find the net carb number plastered on, hmm, tortillas, breads, and other carb-heavy foods. It’s a way to get those on low-carb diets to buy traditionally carb-heavy products while feeling less bad about it by thinking they’re getting less carbs.

Should you care about net carbs?

“Unless someone is on a very low-carb diet, net carbs is sort of a useless number,” says Abby Langer, R.D., MH nutrition advisor.

Like we said before: If you are on a low-carb diet, watch out for net carbs. That’s because you will absorb some of the calories from carbs, which might take you out of ketosis if you’re at your upper limit of carbohydrates for the day.

What everyone should absolutely care about instead is fiber, says Langer. A majority of people are not getting near enough of the stuff. Fiber helps regulate bowel movements and controls blood sugar levels. Men should be getting between 30 and 38 grams a day. High fiber foods include bananas, black beans, chia seeds, and broccoli.

Beware: not all fiber is created equal. The fiber that is added to those tortillas I consumed or other high-fiber bread products are not quite as nutrient dense as the fiber you’d get in, say, a banana.

“It’s generally cellulose powder [in fiber enhanced products], which is an insoluble fiber. While it ‘counts’ as fiber, whole foods provide a lot more nutrients packaged with that fiber,” Langer says. Because of that, she recommends to get your fiber from a variety of sources. “Eating a 17 gram fiber tortilla and calling it a day isn’t going to cut it.”

Prioritize whole food fiber sources like fruits, vegetables, and legumes. Do your best to stay within that 28 gram to 38 gram range—going above it has consequences. Trust me.