Understanding good vs. bad carbohydrates

Is there such a thing as a good carbohydrate?

In short, yes, says author Barbara J. Rolls, chair of the department of nutritional sciences at Pennsylvania State University in University Park, Pa. A good carbohydrate is the one with a lower calorie density—which means fewer calories per bite.

Say you're faced with a bowl of pretzels and a bowl of berries. As one might suspect, the berries have a lower calorie density, making them the better food choice.

Dr. Rolls doesn't believe in vilifying carbohydrates, which make up some 50 percent to 65 percent of the average person's diet. Some people looking to lose weight decide to keep carbs completely off the menu. The problem with that approach, according to Dr. Rolls, is that a healthy range of carbohydrate intake is between 45 percent to 65 percent of a diet.

This figure includes fruits and vegetables, which many people fail to categorize as carbohydrates. Mangoes, grapes, dried fruits, corn and potatoes, for example, all score high in the carbohydrate department, but they're also sources of fiber, minerals and vitamins—and still serve up fewer calories than breads and cereals.

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