I can't really offer anything further, apart from I would say re the whole 'bread thing', bread actually has loads of sugar in it, so I would agree with cutting this out as much as possible.
Curb carbohydrates to just complex carbohydrates and, if you can, look to cutting out as much gluten as you can.
Personally, I don't buy anything for my kids which contain 'Glucose Fructose Syrup' as my son is a tad overweight too and GFS is the devil when it comes to sugars and putting on weight.
Encourage more activity and I quite like the idea of 'treating' her with rewards if she's done well.
Also, at 16 she is able to join a gym, or there are now lots of boot camps around which are a bit more social and 'fun' :-)