Concerned about DC's friend.

[Runrunrudolf]

So DC(14) has their best friend she's always hanging out with at school.
When me or hubby drives DC to school we also take their friend who lives near as her mum works early. Sometimes DC's friend stays for dinner, sleepovers and such.

Well lately I've been noticing some things about her eating. Whenever she stays for dinner she doesn't eat much, she used to to say she wasn't hungry or didn't like it but now she stuffs it far down the bin in hopes we don't know, or gives it to DC to eat.
When I pick her up she has a nice packed lunch which she also goes home with, claiming she brought some food at school or just wasn't feeling hungry.
I talked to her DM who said she often doesn't eat breakfast before she leaves but figures maybe she's just snacky.

I don't know whether to push it further and talk to her? In case I upset her DM by going too far but I'm really concerned she looks more skinny.

do I bring it up with her or her mum? How?

Maybe she just doesn't like your food? I don't mean that in a bad way, but often teens just don't eat elsewhere. It's not always indicative of a disorder (if that's what you are hinting at)

I have considered that but she's doesn't eat much at home and I always buy and cook to suit her desires.
She's always moving it around her plate to make it look like she ate something, hiding it In the bin, feeding it to DC or the dogs when nobody is looking and such.

I'm not jumping straight to ED just a little concerned because I had one at her age I guess