I saw the large posting that touched on this as well as pummeling the health care industry. Every decade we gain another few years on how long we will live, so much so that they want to raise the retirement age. I don't think thats the mark of a polluted society. Sanitation has played a great role in this. Also, people here rarely die of starvation.
Antibiotics are responsible for the elimination of plaques.
Advances in surgery and emergancy care have eliminated a lot of death due to accident. Infant mortality has decreased tremendously due to these reasons. Indeed, when infant mortality is removed, the life expectancy has risen little since the 20's. The chronic dieases and conditions that are the bane of medicine are very much linked to nutrition. I say all this as a backdrop to this statement-the average american diet is terrible and leads to many, many diseases and conditions that the health care industry is baffled to fix.