DEAR DOCTOR K: In your column you often distinguish between "good" and "bad" carbohydrates. What makes a carb good or bad?
DEAR READER: Carbohydrates -- carbs -- occur naturally in a variety of foods, from fruits, vegetables and milk, to breads, cereals and legumes. Carbs are also added to many foods, often in the form of sugar. Your digestive system transforms carbs into glucose (blood sugar). They are your body's main source of energy. Whether a carb is "good" or "bad" depends on several factors. Some of the most important are: