Diet and lifestyle seem to be the main variables. Poorer people tend to eat more processed foods and fast foods out of necessity. Physical labor is less needed to obtain food and water. They are less able to afford visits to the doctor. The obese person using an electric cart to shop at a grocery store in Huntington, West Virginia, or Meridian, Mississippi probably had a great great grandmother who grew her own vegetables, raised her own chickens, and hauled water from a well. They tend to have less of a future orientation, so they defer exercise regimens.
While sanitation and medical knowledge have improved immensely in the last century, the effects of poor diet and lifestyle choices are evident in the disparities among the states.
As a Doctor told my brother when he was discussing heredity versus non-heridity issues in predicting how senior years cardiovascular disease will impact your longevity:
(Paraphrase) Keep in mind that while fish oil, exercise, diet and controling blood chemistry play a part in balancing your genetic disposition to cardiovascular disease, the genetic predisposition will still contol 85% of the advancement with controlable measures accounting for 15%.
How many of the foreign statistics can actually be trusted?
Remember how “Japan is so much better than America, look at all their centennarians” and it turned there was loads of fakery and scamming the system by not reporting grandma’s death and continuing to collect benefits.