When I was a kid (in the '50s and '60s) we didn't have soda and candy or other sweets every day. Maybe on Saturday we were allowed to go to the store and buy one bottle of Coke and a piece of candy.
Never heard of ADHD back then.
"I gotta think that kids today are consuming way too much caffeine and sugar."
It also seems that kids today play outside less, and energy that's not used up by running around can turn into nervous tension.
Its not candy or sweets per se, its the fact the states have made it so that parents cannot discipline there children without fear of reprisal and that teachers cant do it either.
It was earlier referred to as "minimal brain dysfunction," before being changed to ADD, and now ADHD.