[itkovian_]

Completely anecdotal; the amount of people that do not consume caffeine seems overrepresented among very very smart people (i.e. math profs, researchers etc)

[sno129]

On the other hand, the amount of people that consume excess amounts of caffeine also seems overrepresented among such people.

[red369]

It might be that both not consuming caffeine, and being very very smart, have the same root cause - like good sleep patterns.

Just an unresearched thought I had!