Though I can't imagine anyone asking "are you sure you should be eating that" to an overweight person, like that just seems so monumentally stupid. Wtf are you expecting in answer when you ask that. Apparently it happens though.
If they don't ask, they look at you meaningfully. If they don't look at you meaningfully, they pause their conversation.
I literally stopped eating in high school. For four years, I ate nothing - no calories - before 5:30pm. Then at 5:30 I gorged. Then I ran eight miles.
Nobody else can see the stars in front of your eyes but that's okay. You know they're there. They're your halo. They're what make you worthy.
Because fuckin' nobody else will.