Another good read is The Out of Sync Child.
Also, look up information on sensory diets or ADHD diets.
Thank you- the book is now on my list!
We do try to be careful with diet (no red dye except special things like holidays) but other than that we haven't done anything too specific - I'll research a little further. Is there a specific one you recommend?
The Out of Sync Child is in the pediatric occupational therapy realm (sensory processing, sensory sensitivities, etc.) -- it's a very popular book in that field.
ADHD diets are kind of on the cusp of what is considered "acceptably empirically-validated" in ADHD research -- it's still pretty controversial. However, I've had several parents tell me they noticed a marked difference in their child (most of whom were diagnosed with ADHD and/or behavioral/emotional regulation difficulties) once they cut out certain foods. Some of these included sugar (e.g., sugary breakfast cereals, cake/donuts, fruit juice, etc.), processed carbohydrates (white bread, noodles, rice, pasta), gluten, eggs, etc. (not all of them were eliminated for every kid I worked with). In addition, many parents give their kids Omega-3 / fish oil supplements. From my perspective, tailoring a diet that still includes all of the necessary nutrients for the child to grow and develop healthily, that may benefit the child and won't harm the child, is worth trying.
I would start with the common/well-known sites for ADD/ADHD, such as:
https://www.additudemag.com/adhd-diet-nutrition-sugar/http://www.add-treatment.com/adhd-diet.htmlhttps://www.understood.org/en/learning-attention-issues/child-learning-disabilities/add-adhd/adhd-and-diet-what-you-need-to-knowI'd also try books such as:
The ADD & ADHD Diet: A Comprehensive Look at Contributing Factors and Natural Treatments for Symptoms of Attention Deficit Disorder and Hyperactivity
ADHD Diet for Children: Recipes and Diet to Help Your Child Focus, Perform Better at School, and Overcome ADHD for Life
Because this is not a well-researched area, you may want to read several and kind of glean the common elements from them. For example, pretty much every book will talk about processed sugars or food allergies contributing to behavioral dysregulation.
Anecdotally, I've worked with several kids with diagnoses of ADHD, and there is sometimes a MARKED difference within half an hour of ingesting a sugary/carby substance. How do I know this? We have free hot chocolate, crackers, and apple juice where I work, and the kids often take a break to get themselves a snack. For some of these kids, behaviorally, they start Bouncing Off the Walls within 15-30 minutes of their snack time -- they talk more, talk faster and louder, have trouble sitting still, and have more difficulty managing their behaviors. In other kids with ADHD diagnoses, there is absolutely no change in behavior.
In my own neurotypical preschooler, I can see a definite change in her behavior when I feed her cake or sweets in the afternoon. If I give her cake/cookies/sweets, even watered down fruit juice, after 12:00 noon, she will be more whiny and emotional, and will typically have a harder time falling asleep at night even though she's tired.