No links that I can recall at the moment.

Just anecdotal evidence that it is the case. Our guy is anaphylactically
allergic to dairy and other foods. Then there are the "lesser" allergies that
trigger behavioral symptoms, along with other symptoms such as itching.
Sometimes it's only the behavioral.

When he was young, it was hard to distinguish the allergy-triggered behaviors
from the developmentally appropriate or situational. Now that he's 16 - well,
it's easier, but not always simple.

Bottom line is, if a food reliably triggers symptoms and the symptoms
disappear without the food, you have strong evidence. If your doctor (or
spouse or other significant figure) requires reliable proof, schedule a
medically supervised double-blind food challenge. Just make sure they don't
use lactose as a placebo (yup, that's common). Then your "control" may trigger
some out of control behavior.

- Mark