Living with persistent adult acne can be a disheartening experience. It seems to come and go in random fashion, leaving you scratching your head. Reading acne forums and talking to other patients doesn’t always help. You’ll end up with a bag full of conflicting ‘this worked for me’ stories.

The problem is that there’s no good way to make sense of these. You end up wondering why a particular method worked for one person and whether it could work for you, too. Many people simply end up trying whatever they can get their hands on. This can lead to a string of disappointments and take a toll on your emotional life.

In this chapter, I’ll try to remedy this problem, and give you a solid framework for understanding acne. We’ll start by defining terms like distal and proximal causes. As you probably know, many things affect acne, all the way from cellular events in the skin to hormonal reactions following eating certain foods. Proximal and distal causes help you to understand the chain of causality at play.

Then we’ll briefly (relatively speaking) cover how pimples form in the skin and the main things that influence the process.

Finally, we’ll get to the good stuff and talk about acne types, which help to explain why certain treatments work for some people but fail on others.