You can eat healthy away from home, even at fast-food restaurants. If you're ordering fast food, skip burgers with two or three beef patties, which can easily add up to 800 calories. Instead, choose a regular or even a child's hamburger, which has about 250 to 300 calories. Also, skip the large serving of french fries or onion rings and ask for a small serving instead. This switch alone saves 200 to 300 calories.