being obese is something that 90%+ of the time, you have a choice in
A big part of an individual’s build is genetic. Saying you “choose to be obese” is akin to saying you “choose to be tan”. Truer for some people than others, and often more a question of degree than state. But telling a Samoan to just stop being big is about as practical as insisting a Swede needs to stop being so fucking tall.
Nobody picks their race.
Race is a social construct. You’ve got significantly more control over your perceived race than your perceived weight, as even adjustments to your outfit and accent can cause people to place you in radically different ethnic groups.
My sicilian mother was regularly mistaken as hispanic, simply because she was shorter, slightly tanner, knew more spanish than her Mayo-American neighbors. I’ve got a Philippian friend who regularly code-switches between East Asian, Polynesian, and White depending on who is around. And even generic whiteness becomes extremely relative when you’re in Europe. Being from anywhere east of Germany might as well make you a filthy mudblood (nevermind the beef between English, French, Spanish, German, and Italian folks). A bit of accent work and a certain haircut can put you on the other side of the continent.