I agree this is a silly study.
Wealthy people tend to take care of themselves better, physically.
When I go to Walmart, almost everyone there is fat.
When I go to the country club, almost everyone there is thin and fit.
It’s a “class” (not that country club people are better, but skew wealthy, for how I am using “class” here) thing to be thin and fit.
It’s also why Gucci clothes (or whatever) tend to stop at size 8 or so.
Yes, good points.
It’s also a matter of intelligence. Smarter people usually better understand the pitfalls of bad diet and lifestyle than dumber people. A crappy diet is, to my mind, the main component of chronic disease. I believe RFK,jr. feels the same.
And smarter people usually can make more money. And thus pay more in taxes.