Health of People in the United States

Sixty years ago people in the US could boast being among the healthiest.  Health has improved profoundly since then, but other nations have seen greater changes in the same time so now health of people in the US stand in the second tier of nations behind the other rich countries and some poorer ones.  Our health is on a par with Cuba, a nation that has been strangled by the US for decades.  We deserve to be healthier.  Why aren't we?