Diet. Despite what you read, or what some doctors will tell you, it's all diet. Through my research, I believe it has something to do with leaky gut syndrome, combined with waste being excreted through the skin.

My story : I grew up eating a heavy amount of refined grain. I probably ate two bowls of cereal a day on average from the age of 10 to 16. I was always thin, so I, or my parents, never thought much of it. I probably tore up my digestive system big time. From 17 until 22 or so, I had some pretty moderate acne. I'm now 24, and it's gone, but I've got scarring to fix now, so I'm looking into dermarolling and possible surgical options later on. Even though I've been told I look fine, and it's probably true, I cannot bring myself to believe it.

My fix : Removing sugar, and pretty much all gluten containing grains from my diet. I don't eat bread anymore, period. I also eat a ton of vegetables now for fiber, as fiber is great for cleaning your digestive tract. Retin-A cream will also help you skin clear a lot quicker, so I recommend getting a prescription for that.

Everyone is different, so my fix may not be your fix, but good luck.