Are All Carbs Equal?

Many people think of carbohydrates as the "white" foods—bread, pasta, potatoes, cake—but the nutrient group includes vegetables, whole grains, legumes (black beans and lentils, for example), and fruit, which are just about the healthiest foods on the planet. "These are healthy carbohydrates," says nutritionist Bonnie Brehm, PhD, an assistant professor at the University of Cincinnati College of Nursing who has studied low-carbohydrate diets, "and they are full of great nutrients: fiber, vitamins, antioxidants." Processed carbs—the cakes, cookies, white bread—are the ones that are more questionable. They generally carry few nutrients and break down quickly in the body.

 
Do Carbs Make You Sick?

Regularly overindulging in simple, high-GI carbs—the kind that produce the beloved sugar rush—can be dangerous. "There's a lot of evidence that blood glucose spikes are bad for your heart and can raise your risk for type 2 diabetes," says Brand-Miller. "We're beginning to think that type 2 diabetes develops from a process of exhaustion, in which the cells that produce insulin just can't keep up with the high demand, day after day, year after year." Those glucose spikes, says Brand-Miller, are also thought to indirectly cause irritation of the cells lining the blood vessels, which can lead to inflammation and plaque buildup—risk factors for heart disease.

 
Do Carbs Make You Fatter?

Researchers have repeatedly found that all calories, no matter what food they come from, produce exactly the same amount of energy. But a recent preliminary study at the Harvard School of Public Health tantalizingly hints otherwise. Controlling every bite of food subjects ate, researchers discovered that low-carb dieters lost more weight than low-fat dieters despite consuming an extra 300 calories per day—or 25,000 additional calories over the course of 12 weeks, which, mathematically speaking, should have made them lose about seven fewer pounds. The experiment was too small to be considered definitive (though, naturally, it was reported at great length in the press), and the researchers are now designing a larger study to see if the results will hold up.

Other studies, including one by Brehm, suggest that people on low-carb diets do shed pounds faster than low-fat dieters. The longest study to date, however, showed that while Atkins-type dieters lost more weight than low-fat dieters in the first six months, by the end of a year there was no discernible difference between the two groups.

 
Can You Get Addicted to Carbs?

Sugar or bread might incite a craving for more of the same, but no, you can't get hooked on carbs the way you can on alcohol or drugs.

Psychologically, however, there is a powerful drive to eat them, according to Judith Wurtman, PhD, director of the program in women's health at the MIT Clinical Research Center. "The only way your brain can make serotonin—the key chemical that lifts mood—is through your intake of carbohydrates," says Wurtman. Women's brains naturally contain less serotonin than men's, Wurtman says, and when we try to remove carbohydrates from our diets, we can become anxious, depressed, and irritable and have trouble concentrating. "It's not an addiction, because there's no physical withdrawal," she explains, "but when you have those feelings and you've been depriving yourself of carbs, you begin to crave them in order to make yourself feel better."

 
What Does "Net Carbs" on a Food Label Mean?

Net carbs is a diet concept popularized by Dr. Atkins and now co-opted by food manufacturers. "Most of them, it seems, use 'net carbs' to refer to carbohydrate content after they've subtracted grams of fiber and any carbs they think don't spike your insulin," says Brehm, "but the subtracted ingredients are still carbs, —scientists, government agencies, researchers—has officially defined "net carbs," so it's essentially a marketing gimmick.

 
What Does "Net Carbs" on a Food Label Mean?

Net carbs is a diet concept popularized by Dr. Atkins and now co-opted by food manufacturers. "Most of them, it seems, use 'net carbs' to refer to carbohydrate content after they've subtracted grams of fiber and any carbs they think don't spike your insulin," says Brehm, "but the subtracted ingredients are still carbs, —scientists, government agencies, researchers—has officially defined "net carbs," so it's essentially a marketing gimmick.