That’s no mystery. The amount of calories the average person expends has decreased as we’ve become more sedentary. In the 40s, 50s, and 60s most people did man

That’s no mystery. The amount of calories the average person expends has decreased as we’ve become more sedentary. In the 40s, 50s, and 60s most people did manual labor and even office jobs were not as sedentary since you couldn’t just sit at a computer. Here’s another simple overlooked example, grocery shopping, before the rise of superstores you’d go into town and visit 4 different stores. The butcher, the hardware store, the grocer, the pharmacist etc. now it’s all in one big store all next to each other. Here’s another example lawn mowing. Back then most people had manual lawnmowers. Here’s another example the moving of goods. Go look up a picture of the manual labor involved in being a stevedore back then versus now and that’ll give you an idea of how much less physical exertion is needed these days even in jobs that are still considered manual labor. Overall I think solely blaming plastic for obesity is an oversimplification and assuredly wrong, although it could have some affect there are a lot of other things going on. Declines in fertility and IQ are most likely due to obesity so it’s a big issue.