Sugar has been shown not to be responsible for hyperactivity in children. It can lead to irritability though.
https://www.bbc.co.uk/sn/humanbody/truthaboutfood/kids/hyperactivity.shtml
They didn't research my child then Daniel gets hyperactive on sugar and sweeteners. He can have something that is totally natural with no other additives in it but if it has sugar or sweeteners added to it he is bouncing off the walls.
Having read the short article i can definitely say that i never have expectations that Daniel will act in certain ways in certain circumstance. It is literally from having watched him. I have given him something loaded with sugar totally forgetting what it can do to him - within minutes the sugar rush hits in and he is buzzing. It's only afterwards that when taking to my OH that i'll realise what i've done.