Welcome.
The book The Bipolar Child is the most comprehensive info you'll find on Childhood Onset Bipolar Disorder (COBP). There's nothing there, and I've never heard anything in any other setting, that suggests that diet affects BiPolar (BP) or any mood disorder. In a long term way anyway. Personally I'm a depressive and chocolate can make me happy for awhile! Lots of foods can affect our mood in a minor way but it won't affect the underlying illness or offer any real relief.
BiPolar (BP) and Pervasive Developmental Disorder (PDD) are often co-morbid. So you might try the online Pervasive Developmental Disorder (PDD) assessment for some quick insight into whether Pervasive Developmental Disorder (PDD) is something worth looking into. With regard to Pervasive Developmental Disorder (PDD) some people have reduced symptoms with diet changes. Particularly, gluten and casein free diets. Note that it doesn't work for all, doesn't eliminate the neurological issues of Pervasive Developmental Disorder (PDD), etc. But if your child has Pervasive Developmental Disorder (PDD) it's always worth trying as it's harmless.
Since many BiPolar (BP) kids are "hyperactive" and diagnosis ADHD before the BiPolar (BP) diagnosis, same with mild Pervasive Developmental Disorder (PDD) kids, you'll find a lot of others here who have been in the position of not having much luck with stims for ADHD. Of course, ADHD can be co-morbid with either. But if stims haven't helped... actually, they typically make a non-ADHD child more active, irritable, etc.... just as "speed" would. One diet trick I learned from an ADHD Mom is to give my ADHD kid plain Coke. For some kids it calms the ADHD kid for an hour or two anyway.
