Lu - I have found with Luke that the two worst things for him are strawberries & green grapes... for him, they're worse than chocolate, lollies or soft drink in terms of him being on a 'high'

Just re reading your post, it doesn't look like your DS eats them if he doesn't eat many fruits, etc... but I definately notice that anything with 'natural' sugar like that just makes him go crazy....

I know that doesn't really help your situation but look at other foods he eats with natural sugars.