Maybe she just dated an Italian grandmother and hated her. I dunno. I wish her heroes would diversify in body type. Or she could at least stop describing the exact same attribute. I mean, OK, WE GET IT. This character is going to be thin. We can tell from your overshadowing that character X is good while character Y is bad. We don't need to also therefore know their weight. We can extrapolate from the data you've given us in the first three chapters.
Christ Almighty. If John Galt turns out to be a skinny person, I will phlostigenate Ayn Rand personally.