system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How come fat isn’t distributed evenly across the body but instead is in specific places?
gpt
Fat is insulation. It protects important areas. It also cushions us. So like for example, your butt. Your bones wouldn’t be good to sit on, so this is the solution. Your abdomen has many of your most important organs, and doesn’t have a rib cage to keep them safe. 

Your sex hormones are a huge determining factor in where your body stores it’s lipids. Different fats in different areas have specific receptors for hormones. Hormones signal important pathways in your body! 

Fatty acids are what we get when we break down lipids. They are by far the most energetically favorable thing for your body to break down. It doesn’t take nearly as much energy to break them down, compared to the cellular energy we get out. 

Some lifestyle choices, like smoking, poor diet, etc., can determine some of where we store our fat. However it is mostly genetics.