For our guy, protein at every meal is a must and too much sugar is a no-no. At 15 years old, it's hard to get more prescriptive than that - he eats lunch off campus during the week and looks at fruit like it's a peculiar alien species. We do what we can. What foods have you found you need to avoid (or include) to help your kiddo stay on track?
If I had a dollar for every time someone told me "it's probably just a phase", or "he's never acted like that at my house", or "have you thought about military school?" - I would have enough money to pay for all the psychiatrist and therapy bills! It's hard not to get frustrated with them and it's even harder not to feel understood. I still haven't not figured out the right come back for these well-meaning folks, so let us know how you've handled it