I find it super weird that my food intake nor my sleep duration is correlated with my brain use. There are days where I will hardcore hyperfocus learning techni

I find it super weird that my food intake nor my sleep duration is correlated with my brain use. There are days where I will hardcore hyperfocus learning technical scientific papers all day and also deeply think/debate about a complex topics for hours and other days where my brain will be complely un-stimulated and yet as I said, no variation. It's absurd. A tangeant would be: do highly intellectual people have shorter lifespan because their body would trade-off energy for their brain thus limiting the supply on other organs and hence creating deficit in e.g. mitochondria bioenergetics?