The AP article

Running a marathon, grab a carbohydrate bar. Lifting weights, gulp
a protein shake. But climbing into a fighter jet? Butter-soaked lobster might
help.

That was the surprising finding of a new military-funded study that sought to
figure out what types of foods were best for pilots when missions restricted
when or what they could eat. University of North Dakota researchers found that
pilots who ate the fattiest foods such as butter or gravy had the quickest
response times in mental tests and made fewer mistakes when flying in tricky
cloud conditions.

High-carb diets trumped high-protein in performance tests.

Thanks to Paul Thomas