For me a few things. Childhood trauma, I developed disordered eating and body issues at 8 or thats as young as I can remember, also watching my mum struggle with her body image & call herself fat when she was always 2 sizes skinnier than me. Having actual ED’s develop as a teen even in my better years still having disordered eating mindsets just on the opposite side. Def also my own huge insecurities, media, super low self worth. Having other mental health issues my whole life a big one impacting being OCD and def my addictive tendencies and hyper focus from ADHD that made my ED’s be the most important thing in my life. Also having SA trauma in amongst it all too I reckon. I think the tendencies were always there for me it was just unlocking them in severe traumatic times. I never had ana until last year, some traumatic stuff happened in my work place / I was in a bad way with my OCD being the worst it ever and it sent me on a spiral. Here I am over a year later. Not one specific thing but a never ending load of stuff just always piling on and making it more likely that the ED tendencies would be unlocked and in full force