Apples are no more or less fattening than any other low-fat food, but they do have quite a bit of nutritional value. Apples generally contain between 75 and 100 calorie each, with the Macintosh variety on the low side with 70 calories and Red Delicious apples on the high side at 90 calories each.
Apples are a low-GI food and are a good source of dietary fiber, antioxidants and phytonutrients. A 2011 Forbes article states that the pectin in apples binds with water, which may restrict the amount of fat your cells can absorb. The high amount of dietary fiber also creates a feeling of fullness, making them ideally suited for a before-dinner snack.