i've been Dxed anorexia nervosa type 1 a few years ago...currently i am weight restored.
when i was a kid ages about 9-12 i started purging. i didn't realize what i was doing was disordered at the time, though. i was a gymnast and really intense about it. things were also rough at home and there was some extraneous abuse as well. controlling my own sickness was a sick comfort i guess.
funny thing is after i stopped i became emetephobic.
i can list a few reasons why i think my ED and my AS feed each other.
-food sensory issues
-deep, obsessive focus
-need to do things the "right"
way, habitual
-the numbing effect of starvation
-being small is much more comfortable and from an external perspective, being small makes people accept my awkwardness more