[throw310822]

Yes, these numbers make the discussion a bit more concrete. But 5'7'' and 150 is definitely in the healthy weight range- girls can strive to be thinner than that but it's to fit some arbitrary idea of beauty rather than to, as you say, "be treated better in each aspect of life" (yes of course, attractive people in general are treated better- but it should be a negligible effect for the ranges we're talking about). In other words, I assumed that the user you were talking to was talking about much higher BMI indexes than these. Personally, as a male, I don't find the 5'7''/ 150 unattractive at all- though it also depends on how fit someone is.