eating like a horse

In the two days after treatments Fiona gets hungry. Really, really hungry. After her first IVIG she came home and ate almost as much as Christian and me. After a particularly memorable treatment she shoved handfuls of chicken into her mouth as fast as I could cut bite sized pieces. She seems to love protein and chocolate lately. Before she was diagnosed she loved fruits and vegetables, now it's hard to get her to eat them. I wonder if this is just a normal toddler phase or if this is her new way of eating?