From today's BBC on line (http://news.bbc.co.uk/2/hi/health/778...), report of a recent study published in the British Medical Journal:
"Regardless of what parents might think, sugar does not cause hyperactive behaviour.
At least 12 randomised controlled trials looking at levels of sugar and behaviour - even in children with attention deficit hyperactivity disorder - were unable to detect any difference.
Scientists also found that when parents think their child has had a sugary drink they rate their behaviour as more hyperactive - so it is all in the mind."
Fascinating! We believe what we want to believe.