For such a complicated subject, this is a very fast read. What I know about anorexia is that it is an obsession disorder that can kill. Like most obsession disorders, it is very hard to treat because, while the effects are physical, the cause is mental. You wouldn't think thoughts can do so much damage, but they can. And like a mostly harmless earworm, those thoughts are very hard to remove.
I enjoyed the story. Like I said, it is a fast read. It is not a sad book, while there are sad things that happen. The way our Anna falls into trouble is well documented. The only quibble I have is that Anna's first recovery seemed a little fast. The book suggests that, after about a month in the treatment center, Anna is well enough to go on outpatient treatment where she will be successful.