There have been quite a few studies about the connection of ADHD behavior and certain foods and additives. The studies have, for the most part, found there are no links between the two. Some of the foods believed by many to have an affect on ADHD behavior are: artificial flavors and colors, some preservatives, sugar, caffeine, and some fats. I know many ADHDers, and many of them have been on diets that cut out foods with those ingredients. The diets made no impact.