Obsession with food

Hello, I'm new to the forum

My daughter (5) has difficulties with overeating and obsession with food (ANY and ALL food). She's been seeing a pychologist since 2 but they have advised unfortunately this will now come to an end, as she has the diagnosis of autism / aspergers and her food issues are part of that.  

From my very limited experience (she's newly diagnosed)  I think that the opposite seems more usual for people with ASD and so I've found it extremely hard to find any info re overeating difficulties.

Wondered if anyone had experience or resources re this particular difficulty.

Thank you in advance, not to worry if not as like I say it seems that maybe the opposite problem usually presents more often.