When someone loses weight how does it go and where does it go?
Your body is an energetic machine. It needs a constant supply of
energy to do work: moving your muscles to run, carrying objects in
your environments and maintain basic cellular processes. To keep a
ready supply of energy, your body stores this as potential energy
in the form of chemical bonds that make up fat. So when you lose
weight, your body breaks down this stored fat, releasing the energy
to keep your body functioning. This energy goes towards doing
useful work, and much of it is also expelled as heat. A small
portion of these metabolized lipids would be excreted, but most are
probably recycled in other cellular processes.