Yes and no. You're forgetting that majority of primal human diet wasn't meat, it was whatever the gatherers acquired during the day, because hunts weren't always successful and weren't done every day either (sometimes it would take days just for one hunting trip depending on the distribution of pray animals). I mean you go out with a spear or bow and arrow and see if you can hunt down a deer every day. The gathered goods would include anything from plants to insects, rarely small animals. You are right about us evolving to eat real food, however, you are forgetting that fruits/vegetables are also real food. And if you're gonna pull the argument that modern vegetables are very different from the ones in cavemen times - so are the domestic animals/meat.  I do agree about the sun though, sunnier countries seem to have a lot smaller rates of mental illnesses as well (like depression or anxiety). Diseases are not a result of deviating from the meat and sun, because they were always present. It's just a way to regulate the population because every ecosystem on the planet has limited amount of resources, and if any species was to overpopulate it, it would lead to a catastrophe - as you can see from examples of invasive species, the worst one being humans.  It's late and I've had a long day, so cba to provide sauce for the shit I said, but use the google machine.