What causes some people to develop eating disorders

Insecurities are some of the reasons

I developed anorexia at a young age from feeling insecure about my weight. I got bullied for being fat and other things (even though I was a skinny child).

Most of the time it's insecurities caused from bullying or being a chubby child (etc.)

Sometimes it's seeing your partners as bigger and you start to get paranoid and develop a eating disorder.

There's many ways.