My cysts were worse than they've ever been in my life at a time when I was eating more sugar than I have in my life, and they got better when I drastically changed my diet, removing a lot of sugar and adding a lot of protein. Now, I NEVER get cysts.
I don't know, you can look up the sugar/cystic acne relation...there is a lot information out there. Some people don't believe there is a connection. But that's what worked for me. It was an accident too. My cysts were AWFUL but I was trying antibiotics and some other stuff from the doctor. Then because of unrelated health problems, I was forced to change my diet. I just happened to notice that the diet change seemed to have a big effect on my skin too.