When a Carb's Not a Carb: The Net Carb Debate

Will counting net carbs help or hurt weight loss efforts?

By Jennifer Warner
WebMD Weight Loss Clinic - Feature

Reviewed By Michael Smith, MD

When is a carb not a carb? That's the question many carb-conscious dieters are facing as they struggle to keep their carb counts within the strict limits recommended by Atkins and other low-carb diets.

In an effort to cash in on the low-carb craze, food manufacturers have invented a new category of carbohydrates known as "net carbs," which promises to let dieters eat the sweet and creamy foods they crave without suffering the carb consequences.

But the problem is that there is no legal definition of the "net," "active," or "impact" carbs popping up on food labels and advertisements. The only carbohydrate information regulated by the FDA is provided in the Nutrition Facts label, which lists total carbohydrates and breaks them down into dietary fiber and sugars.

Any information or claims about carbohydrate content that appear outside that box have not been evaluated by the FDA.

"These terms have been made up by food companies," says Wahida Karmally, DrPH, RD, director of nutrition at the Irving Center for Clinical Research at Columbia University. "It's a way for the manufacturers of these products to draw attention to them and make them look appealing by saying, 'Look, you can eat all these carbs, but you're really not impacting your health, so to speak.'"

Although the number of products touting "net carbs" continues to grow, nutrition experts say the science behind these claims is fuzzy, and it's unclear whether counting net carbs will help or hurt weight loss efforts.

What's in a Net Carb?