It was in English
In color
Remember watching it 25 or so years ago
Can only remember a small part where a girl was in her grandmothers living room, all around the room on a high ledge were boxes of posh chocolates. She asked for one and was told no, so she snuck a box and ate them, and then put the box back, over time she kept doing this until all the boxes were empty.
I can’t remember if she was caught but I remember her teeth turned black.
Please help
An Angel at My Table directed by Jane Campion http://www.imdb.com/title/tt0099040/?ref_=nv_sr_1 It’s the biopic of Janet Frame, and the scene you describe is when she stays with her aunt while attending college.