I remember my 1st car, didn't have A/C. I was bummed, but happy to have my own ride at 16. My dad was like, it has A/C dumb ***. Two windows down and 60 mph.There were lots of obese folks before fast food but not anywhere near what there are now. The degree of obesity has exploded. The only morbidly obese people I can remember from the 60s were post-menopausal stay at home moms cooking for a litter of kids. We’re a wealthy nation with virtually unlimited access to French fries, pop and sweet snacks. Then there’s air conditioning. Working construction in the early 70’s I had a body fat of about zero because I was too exhausted and hot to eat. NOW? Almost everybody has whole house AC.