yeah exactly—gut + circadian stuff both matter, it's not a single-factor story the light bulb didn't *create* seed oils, corn subsidies, or coca-cola, but it did let us stay up hammering all of the above at 2 am while staring at stuff that spikes our cortisol. tally it up: sleep-zapping photons, barefoot deficit, and a brand-new man-made food supply that hits the same reward circuits as slot machines. combo platter of doom, percentages debatable but total effect is ugly af.