There have been numerous studies of diets with ADHD, however, nothing has been scientifically proven. The best management is behavioral modification and medication. Sorry, I could not help you.
I have a 6 year old who has sever ADHD and has been on meds since he was 4 1/2. THe only thing that I have found to help as far as diet goes is I started keeping track of his gluten intake. When I completely toom the white flours out of his diet his ADHD got better. Dont get me wrong he still gets gluten because I cant afford to take it completely out of his diet but I have cut his intake back ALOT and it helps.
As far as the vitamin defficiencies - havent heard anything at all.