Color me a sugar skeptic. I've watched plenty of kids whose parents assured me were made "wild" by white sugar, corn syrup, or unrefined carbs in high-sugar situations, and all of them have been able to control themselves with me. "This cake or candy is for children who can eat it and remain in control and well behaved," with a brittle smile, has always worked very well. "If you think you might get crazy when you eat this, you should excuse yourself because we all want to have a fun time."
I've never had a kid refuse, and I've never had one turn into the overwrought mess that I have to endure at some parties. I have had kids think for a moment then decide that they will be able to handle it, after all, just this once. The parents think I am magic.
EVERY double-blind study shows that "sugar-sensitive" kids react to what they and their parents THINK is in something, not what's actually there.