Will also stick my neck out and admit that DD and DS have these very occasionally.
e.g. out at soft play places, over my mum's house.
We also buy them occasionally if going out for the day.
They don't have any discernable effect on DD and DS at all.
At home they drink water and DS drinks milk in the mornings.
I don't think there's anything wrong with a litte bit of everything in moderation!!!!