Carbohydrates do not make you fat, but eating too many calories can. The key word here is calories. No matter whether the calories come from fat, protein, or carbohydrates---if you eat more calories than you burn, you will gain weight. Cutting “carbs” from your diet can cause weight loss because many of the low carb plans limit total calorie intake. The body uses carbohydrates for energy, and going too long without them can cause you be tired.

Additional Resources:

http://www.care2.com/greenliving/carbs-dont-make-you-fat-calories-do.html#