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...