This is interesting – I know of pretty much nothing that has looked at this in school children. All of the research appears to be animal based, which is difficult to translate.
There’s a good amount of decent research on exercise and ‘healthy diet’ and cognitive function, but very little really convincing stuff on specifics of diet. I’m sorry, I don’t think I’ve been particularly helpful.
I’m not a nutrition expert but i know that the literature supports the importance of breakfast on cognitive performance during the day. Ensuring children have their breakfast seems the clearest message (not always easy with sleepy teenagers). What is less clear is the optimum composition of the breakfast. A recent review said tentatively ” the macronutrient composition of the meal per se may be important with respect to both performance efficiency and mood: specific foods and nutrient combinations (eg, carbohydrate and protein) may influence
blood glucose and insulin concentrations, acting on brain neurotransmitter synthesis” but concluded there was insufficient evidence whether different breakfast meals “selectively facilitate different cognitive domains”.
Edefonti, V., Rosato, V., Parpinel, M., Nebbia, G., Fiorica, L., Fossali, E., et al. (2014). The effect of breakfast composition and energy contribution on cognitive and academic performance: a systematic review. [Review]. American Journal of Clinical Nutrition, 100(2), 626-656.
@Paul Howard-Jones provided what I believe is the best study to date on nutrition and cognitive performance. There is much more evidence that suggest malnutrition has negative impacts on cognitive performance. Aside from protein, literature suggests that fruits and vegetables have a lot of the vital nutrients needed for brain function. We are about to start an intervention looking at fruit and vegetable consumption (as well as fitness) in a 6 week period looking at improvements in cognitive performance. I’ll make sure to share results when they become available.