By the end of the program, esp with the 5 -2 diet thing, it seemed to me that it wasnt eating less made us super healthy just that eating lots makes us unhealthy.
Seems to me that having some days when you dont get enough, or at least not too many, calories should be the default (ie at some time in the year people should struggle to eat enough).
It almost seems like there’s some sort of self destruct mechanism for times of plenty built into mammals (at least). This would make sense from an evolutionary viewpoint as if there is plenty of food you might as well try and get through as many generations as possible so the species keeps evolving.