Such a significant behavior change across a large population is not well explained by "we just did".
I'm not sure fast food consumption or huge portion sizes is a great explanation. If fast food is the problem, why does that matter if it just comes down to calories? As for larger portion sizes, would even larger portions make us continue eating? Would tiny portion sizes make us all deadly malnourished?
We do know that walking rates, across the country, have fallen significantly. In 1969, approximately 50% of children walked or bicycled to school, with approximately 87% of children living within one mile of school walking or bicycling. Today, fewer than 15% of schoolchildren walk or bicycle to school. And we see this generally across the board, where for the most part driving to work alone dominates commute habits. If the only walking you do is from the door to the car, you are not getting much routine physical activity.
This would also actually well correlate with the rate of fast food consumption, since it's primarily car-centric, and is more car-centric than other types of eating out.
https://www.saferoutespartnership.org/sites/default/files/pd...
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I also don't think it's really any sort of secret that fast food companies like return customers and engineer the types of food that become addictive. There is a book called the Dorito Effect which theorizes that not only has artificial food become more flavorful over time, but that our industrial scale food production has made the base products less flavorful in favor of prettier or hardier varietals.
The reason a population gains weight is way more complicated and probably best short-handed as “social”. Moving to America typically makes people gain weight. Leaving it leads to weight loss. If you’re trying to fix an overweight population, you need to look at lots and lots of things and, demonstrably (as in: the science is pretty clear), telling people to simply eat less and even very expensive high-touch interventions aimed at diet correction don’t work. Wrong tree to bark up, your solution lies elsewhere—or, probably, several elsewheres.
(But drugs might work!)
Have you been in a US supermarket? It's absolutely nuts and I don't think many Americans realise it.
To be bombarded with monumentally huge portions of everything is just a recipe for...well....the situation the US is in. Theres not many other countries that have whole food groups focused on cramming in as much peanut butter, jelly, marshmallow, chocolate, or whatever other high fructose corn syrup crap is being used.
Massive slices of cake prepackaged and ready to eat? Yeah why not. 50 different coffee syrup flavors? Yeah go for it. How about a lovely massive bottle of sugary drink to wash it down? Just one? No no have a crate of 20 of the things.
Just for a comparison, look up candy on the Walmart site. Now do it on Tesco UK. Next, try the bakery, or hell even the meat isle, somehow the exact same product ends up being significantly worse for you in the US.
Would gratuitously large steaks in the meat section and huge rotisserie turkeys instead of chicken at Costco produce the same result?
It seems strange to pick on certain types of foods unless believe those foods are the cause of obesity instead of just eating too many calories of any kind.
If you think cookies and candy are bad but other things are not, why? Is it that they are easier to over-eat? If so, how does that compound over time, given humans are trying to maintain homeostasis which includes a healthy set weight via satiety. Exercise induces more calorie consumption later. Over calorie consumption also induces lower consumption later. This seem like relevant factors.
>Does it matter if those calories are a prepackaged cake or candy? In the end it is just calories.
In the end it's a complex, poorly understood network of hormones and brain chemistry. Human action is mostly downstream of that.
Also, eating more in isolation and without talking.
It must be something about the ingredients (invalidating calorie theory) or it must be lower calorie (invalidating ingredient theory).