ABSTRACT
The old saying goes that little girls were made of “sugar and spice and everything nice” and little boys were made of “snakes and snails and puppy-dog tails.” That definition might have sufficed when we were young, but as adults we know that what we are made of is a lot more complex. Furthermore, changing what we are made of through weight loss and improved fitness all too often proves very challenging. In this chapter we will explore the basis of body weight and composition and what it takes to lose weight and keep it off. We will also take a close look at the two biggest contributors to our body weight, namely muscle and fat, and how they impact our health.
