[KyleGoetz]

Lots of Americans say "such and such isn't my cup of tea." Well, usually you hear "ain't my cup of tea" in Texas, but it's the same construction, just different verb conjugation.

I would keep "physical health personified" because the translator chose that form and there's absolutely no reason to prefer "the personification of physical health" over "physical health personified." Unless you think "personify" isn't a valid verb.

In my neck of the US, we tend to use "sick" rather than "ill," but they are interchangeable in this context.

And to explain MMM's distinguishing of "nothing she won't eat" and "nothing she can't eat," the difference is subtle and not that important for a junior high speech.

"Nothing she won't eat" matches with the "monster" comment because the "monster" comment is insinuating that she's like an animal, indiscriminate in her eating. Thus, you express her desire with "will not."

"Nothing she can't eat" would match "she has an iron stomach" or something of that nature. By using "cannot" instead of "will not," you are emphasizing her ability, rather than habit, to eat a wide variety of things.