Fwiw I think it’s patently obvious behaviors can influence people, but in my mind they influence the avenue of expression - they don’t create disorders from scratch. So like e.g. body image would be the underlying disorder, and if it expresses as bulimia or anorexia or cutting could be somewhat “socially contagious”.
What does seem right to me is if you feel fucked up about your body and your attractiveness, how you express that can be influenced by what you see other people doing. But if you feel confident about yourself there is no amount of hanging out with people with eating disorders that will give you one…
If you’d like to link a paper that has informed your understanding, i’d be happy to read it. But telling me to “read up on it” is a weird dodge of a direct question. Have you read up on it?
I have read a little, not a lot - but what i have read makes a case for some influence of social groups but doesn’t make a case for eating disorders being contagious like viruses.
From my anecdotal experience with people I've known, it makes sense that the other symptoms in that spectrum, like bloating and anxiety, could make someone more receptive to unrealistic body standards and "solutions" to achieve those standards and regain control. That's what it's really about: not feeling in control.