I'm with Faduckeggs...

Sounds like someone who presently has an intact metabolism and normal insulin production and response.

She's lucky and it sounds a little like you're envious. don't be. Luckily there is a way for you to eat that can keep you healthy. Embrace it.

I will say this. If she is intaking very little protein and she doesn't do any weight trainng, I can bet your bottom dollar she has the "skinny fat" syndrome. Not a good look (maybe in your clothes) and definitely not healthy.

Progress not perfection.

Lisa