Probably all that's going through the stomach has one effect or another...
Ever watched kids behaviour before and after sugary and non-sugary meals?
There seem to be a bunch of studies indicating that it is not the sugar that affects the behavior
And anecdotally, both my partner and I can recognize adverse psychological effects in myself after I consume too many high-glycemic carbs (ie, sugar).
Now, this is not a study but covers what I thought was the case since years back:
>The sugar-hyperactivity myth is based on a single study from the mid 1970's in which a doctor removed the sugar from one child's diet and that child's behavior improved. Since then, over a dozen larger studies have been conducted and not one of them has found that sugar causes hyperactivity. Interestingly enough, researchers have found that parents are more likely to say that their kids are overly active when they think they've consumed sugar.
https://www.eatright.org/food/nutrition/dietary-guidelines-a...
Yes, and I've never noticed a difference. I believe that "sugar rushes" are imaginary.