IMHO, falling life expectancy is a macro measure of multiple failing institutions, not a singular cause.

Obesity is driven by systemic commercialization and sugaring of our food supply, combined with inequality of too low a pay, too many hours, to little vacation. Even funding of highway and road infrastructure over other areas is a contributor here.

Another large part of it is because we elect to keep both private health insurance policy which ends up being racially and economically biased, and what little social safety we provide is riddled with self-imposed rules of means testing and other red tape cutting the effectiveness of even the meager allocation of resources. Many very easily and economically preventable illnesses and deaths keep happening and that is a decline to me. e.g. https://www.propublica.org/article/black-diabetics-lose-limb...

Let us imagine that starting tomorrow every single American is granted infinite endless and free access to anything available at any restaurant or grocery store or other food service. Do you think that in 10 years the obesity epidemic would be: better, same, worse?

I have trouble imagining that it would be better. Look at people who come into access with large sums of money for reasons outside primarily mental achievement - athletes after leaving pro sports, musicians after they stop performing, actors after they stop acting, lottery winners, and so on. Some quick searching turned up articles like this [1]:

"The researchers found that the athletes' weight held steady for over 100 years, with the majority of them weighing in at what is considered "normal," -- i.e., with a body mass index (BMI) between 18.5 and 24.9. However, around 1991 the average player's BMI began to rise, and over the last 25 years nearly 80 percent of players fall into the overweight or obese category with a BMI above 25. "

There's a strong correlation between socioeconomic status and obesity, but that doesn't mean it's causal. Obesity is primarily driven by a lack of impulse control. If you force yourself not to over-eat, you could live off of even McDonalds without becoming obese.

[1] - https://www.sciencedaily.com/releases/2016/09/160930085937.h...

This is misleading for athletes and the article is clear that the BMI increase could be due to sports nutrition and new training methods.

Good science always leaves the door open to alternative explanations, even when it may be unlikely. In this case the researchers were relying on BMI to measure obesity. BMI doesn't account for musculature. To not even consider this possibility would be the domain of agenda-driven research, which this paper clearly was not.

Here is a link to the actual paper [1]. Their concluding statement was:

"Professional athletes are not immune from the growing obesity crisis and may not provide optimal role models of health. Concussions have drawn attention to overlooked long-term health consequences of sport participation. Increasing body mass in professional baseball players warrants similar attention for its potential impact on long-term morbidity and mortality because these players hold a special place as role models of health and human performance in our society."

[1] - https://sci-hub.se/10.1016/j.orcp.2016.09.003

Spot on. BMI is a bad indicator of individual health and fitness. I have a BMI of 25 right now but that’s because I added 14lbs of muscle over the last year while dropping a couple pounds of fat. Body fat percentage sitting at 18%.

Now, there are lots of big boys in the NFL that definitely have a couple extra pounds on them, which could also be skewing numbers.

It would be an accelerant for sure, but maybe there would be a self-selecting correction: people with no self-control over food intake would just die out over the centuries (assuming there are genetic and cultural factors involved in food intake south control).

Other leading economic nations have increasing obesity alongside increasing life expectancy.

And why is obesity rising so quickly in nearly all first world countries but particularly in the US? Most of the research points at three reasons:

1. Modern food systems - fast food, frozen boxed food, and a severe lack of access to healthy whole foods

2. Income inequality - Obesity rates are far higher in lower income people and healthy food is far more expensive

3. Work culture - We work far more hours and far less physical jobs. Less hours to exercise and more cost to exercise.

Sure individuals can find ways around all these issues but the more roadblocks we as a society put in people's way the more that will fail. Which is is exactly what the OP is talking about, major scientific and economic issues cause far worse health outcomes.

Folks in the US are on average very fat and very ignorant, not a great combination if you would prefer to have people that are healthy and/or capable of improving their own life.

Well politicians in US grew very fat and very ignorant ppl, so ppl are ignorant and fat.

In other countries where politicians care about citizens -> situation is completely different.

It all depends on agenda and food you sell to ppl.

The obesity rate is up to 42% now and still climbing.

https://www.tfah.org/report-details/state-of-obesity-2020/

This is closely correlated with the COVID-19 death rate.

https://www.wfae.org/health/2021-09-30/novant-says-9-of-10-c...