We need some definition of pesayim. It seems t be used as “I am such a baki in gemora that I do not have time to learn about health”. Do I misunderstand?
I would define it as a non-intellectual and disorganized person for whom it is a tzaar to read, and to follow, health recommendations. Anyone who has a sharp mind and a learning seder should be able to do the healthy stuff too. If he does not, he is not a talmid of Rambam or Shmuel …
We talked before of R Kamenetsky who tried to rely on shomer pesayim on smoking (in 1950s?), but immediately changed his mind when toild that it might affect his memory and, thus, learning. FWIW, current Alzheimer research says that there are no effective late interventions so far, but healthy behaviors (exercise, food) in 40s and earlier, as well as challenging your mind, have effect.
PS this is written in the healthy spirit of “do as I say, not as I do”