Obesity did not originate in the 80’s, I think it started with baby boomers being fed extra well by moms who had been through The Great Depression and WWII. A chubby baby was a healthy baby, and all that. But by the 80’s, fast food had been around awhile and changed a lot of eating habits, no argument there.
I have my Mom’s diaries from the 30’s, and she chronicled her life to include her shopping lists and meals she prepared. Read any recipe book from way back and the portions were much smaller, though the ingredients were not necessarily “heart-healthy” by today’s standards. Mom did serve very well-balanced meals.
I think their lives were much more physically demanding than now. My grandmother kept a two story house spotless for my grandfather and great-grandfather by herself well into old age, no maids, no Swiffers, no clothes dryers, no dishwasher.
I agree with you that fat is not the main culprit, and we also can’t forget genetics.
Genetics ... probably have less to do with obesity than anyone wants to admit, though genetics have everything to do with what foods an individual can turn to for optimum health. Some of us are lucky enough to be able to do dairy every which-way but loose; others develop lactose intolerance. Some of YOU are lucky enough to be able to eat nice oily fish like salmon, or delectable Macadamia nuts, out the ying-yan; others like me have genetics where even a slight overdose of vitamin E-heavy foods, fish oil, or macadamia nuts make us ill.
But as for obesity, and Rush Limbaugh's sad rationalization that some people are just "born" to be able to eat whatever they want and never get fat: I come from a family where that is said of pretty much all of us, because we all eat like horses (you should have seen my tiny grandmother, piling her plate and going back for THIRDS and she never weighed more than 102 pounds). The thing is that the selection is heavily dominated by animal and dairy protein, plus lots of vegetables, with starchy carbs pretty much relegated to side-dish status or as smaller ingredients in a protein-dominated dish.
So you got identical twins (my brothers), literally CLONES, genetically, CLONES. One got married to a woman who fed him a typical America diet high in carbs and processed foods, but supposedly low in "unhealthy" fats. HE ACTUALLY GOT BEEFY, headed toward pudgy!!! While his clone brother, a bachelor who continued to eat our way, which is more or less the "diet" advised in the article, remained and still remains exactly the type Rush Limbaugh would whine "can eat anything and not get fat." Having seen how two genetic clones respond to differences in diet opened my eyes to THAT myth, though poor ol' Rush needs to believe it. A lot of people do.
As for exercise -- all the folks in my family are amped. Hyper. Energetic, always running around and doing stuff. I'm the ONLY one who goes to the gym, and the only one (except for my mom and dad) who has ALWAYS exercised, but the reason for that exercise is this: imagine having a big rangy Irish setter and keeping it cooped up in a tiny apartment all week long. It would drive the dog nuts. Same thing for me -- if I didn't exercise, I'd be like that poor dog cooped up with no room to run.
But when very lean, trim, skinny CLONES illustrate how one of them can become FAT on a "normal" America diet while the other one who follows this unconventional wisdom that fat doesn't make you fat remains lean ... that tells me genetics have a lot less to do with obesity than just plain eating the WRONG food.