Don't worry, be happy - with your body
Of course body dissatisfaction is associated with later developing an eating disorder.
Unfortunately, the 'of course' for me and the 'of course' for many others in the ED community is very different, I'm afraid.
Most say 'of course people feel bad about their bodies with all the obsession with thinness and the obesity crisis and skinny models and sexualization of women and all that pressure leads to people dieting and making themselves sick.' In other words, the amount of pressure leads to greater and greater symptoms and dissatisfaction. Therefore: prevent the dissatisfaction and help people feel better about themselves and eating disorders will be less severe or even prevented.
That's not my 'of course.' I see it as obvious that you'd see greater symptoms of body dissatisfaction in people who later go on to have eating disorders as an early symptom of a brain that is pre-wired to latch onto such messages and magnify them no matter what the level of pressure. I see certain people's brains as attracted to such messages and the real problem is that society has pretty much adopted the thinking of a severe mental illness as if it was healthy and normal.
That normalization of mental illness makes society toxic even for those without the brain problem: causing us to eat poorly, mistreat our bodies, and treat ourselves and others with disrespect and unkindness. That normalization of mental illness masks treatable illness, delays diagnosis, stymies treatment, and undermines recovery. This misunderstanding about the nature of eating disorders leads to misguided treatment, misguided public awareness campaigns, misguided research targets, and bad healthcare policy.
In my perpetual quest for the illustrative analogy, let me try these:
Putting happy face stickers on everything doesn't prevent depression.
Telling people not to worry so much about germs doesn't prevent OCDs.
Helping people love their bodies doesn't prevent eating disorders. It's lovely, it's good, it's positive, and it should be done - but people don't get eating disorders BECAUSE they don't like their bodies and it isn't treatment to teach them to love their bodies. We all need to do that anyway. We do need to prevent DIETING, which is the gateway drug to mental illness for those with a predisposition, but it doesn't seem to matter if the initial restriction was a deliberate diet or a flu or an overzealous track season - and recovery isn't that much different regardless of the initial reason.
We would not be surprised to learn that people who have a history of being sad later develop depression. We wouldn't consider it a "risk factor." We would not try to prevent depression by assigning clowns to every streetcorner or banning obituaries. We wouldn't treat depression by surrounding the patient with happiness.