This may sound cynical, but I believe it is also factual: in a capitalist society, generating revenue by making people sick (junk food), and then generating more revenue by curing them, and finally making a big pile by keeping them alive for a few more weeks, is the way it's "supposed" to work.
If everyone stayed healthy and then peacefully died one day in their sleep, I can't imagine how many $$$trillions that would remove from the US economy. (I know, there's an argument that healthy people would find other ways to generate revenue, but we have no path to realize that.)
Of course, a century of non-capitalist societies don't have a great track record either!
Thank goodness for all those countries that are neither the US nor puely non-capitalist (not that the US is an example of a pure capitalist society).
Just how blinkered is American Exceptionalism anyway? Surely you're knowingly playing up the false { US | not-US } dichotomy.
eg: "American junk food" as seen in the US is largely regulated away in Australia, food labelling is better, overall health and life expectancy is better, etc.