My children are low carbing and they have 'calmed' down alot.
On 48 hours they talked about kids not getting enough sleep. These kids snored and had sleep apnia.
Another article I read said, kids with low magnesium also show signs of ADHD, OCD, and other anxiety disorders.
I put my kids on Magnesium recently and I'll let you know if I notice anything. (My kids will be back home in a week).