Fascinating discussion all and thanks for raising some of these issues and great to hear of the interesting research being done.
I have often wondered about the connection between illnesses, hormones and brain changes. I went to an ED family support group at our CAMHS a few weeks ago. 7 families were represented in all. 3 or possibly 4 of the families had another non ED sibling with autism which I thought was rather high.
Curiously my d entered psychiatric unit for suicidality and s/h and went on to an ED unit. The psychiatric unit was keen to look into family reasons for the psych issues but all they could come up with was we were not very emotionally expressive. I'll hold my hand up to not being a perfect parent but this seemed weak in terms of causality.
In contrast, the ED unit took the modern approach with no blame on parents and so FT was much more along the lines of 'ED explodes into families how can we help you all recover?' As a parent this is much more empowering and speaks to the fact they get there is something going on in terms of brain/hormones/genetics and see the family as being part of the solution.
I mention this because for my d (now out of IP and under CAMHS) all her issues are inter-connected yet the approach from the psych world is very different depending on which behaviour they are focussing on.
In addition, my d had chronic fatigue on and off from aged 7. One of the issues she experienced is lack of cues for hunger and sleep. Also, it is not uncommon for those with CFS to experience depression and anxiety - possibly as a result of this awful illness but also there is possibly a link between continual anxiety (caused perhaps by issues with adrenal gland) and the stress this puts on the body.
I was also reading about changes during puberty and the idea that with a lot of moving parts, things can 'break' This is hardly scientific I know, but more research into this time of change would be welcome. What if much of what we see in psychiatric illneses are related to hormones and such like? Think of the time, hurt and money that could posssibly be saved in treatment.