It occurs to me there's two uses of the word "unhealthy". There's one which is factual and judgement free and applied to like cancer - because you have no control and it only affects you. Then there's the kind that labels presumably dangerous and threatening things - like substances with toxic chemicals, people with toxic personalities, and fat people. When fat people are labeled as "unhealthy" they're treated with vitriol because they're seen as some awful contagion that might rub off.
This is really well said. Thank you.