Maybe there's a deeper reason for Americans' ill-health:
Scientists have long surmised that moods affect health. But the underlying cellular mechanisms were murky until they began looking at gene-expression profiles inside white blood cells. Gene expression is the complex process by which genes direct the production of proteins. These proteins jump-start other processes, which in the case of white blood cells control much of the body’s immune response.
It turned out that different forms of happiness were associated with quite different gene-expression profiles. Specifically, those volunteers whose happiness, according to their questionnaires, was primarily hedonic, to use the scientific term, or based on consuming things, had surprisingly unhealthy profiles, with relatively high levels of biological markers known to promote increased inflammation throughout the body. Such inflammation has been linked to the development of cancer, diabetes and cardiovascular disease. They also had relatively low levels of other markers that increase antibody production, to better fight off infections.
The volunteers whose happiness was more eudaemonic, or based on a sense of higher purpose and service to others — a small minority of the overall group — had profiles that displayed augmented levels of antibody-producing gene expression and lower levels of the pro-inflammatory expression.
What this finding indicates, says Steven W. Cole, a professor of medicine at U.C.L.A. and senior author of the study, published last month in The Proceedings of the National Academy of Sciences, is that “our genes can tell the difference” between a purpose-driven life and a shallower one even when our conscious minds cannot. Of course, genes cannot actually perceive or judge our behavior, so the shift in gene expression is very likely driven by an evolutionary strategy of working for the common good.Looking to Genes for the Secret to Happiness (NYT) See also: The Surprising Reason Americans Are Far Less Healthy Than Others in Developed Nations (Alternet)
If Americans exercised more and ate and smoked less, this conventional wisdom holds, the United States would surely start moving up in the global health rankings.
But many epidemiologists — scientists who study health outcomes — have their doubts. They point outthat the United States ranked as one of the world’s healthiest nations back in the 1950s, a time when Americans smoked heavily, ate a diet that would horrify any 21st-century nutritionist, and hardly ever exercised.
Poor Americans, then as now, had chronic problems accessing health care. But poverty, epidemiologists note, can’t explain why fully insured middle-income Americans today have significantly worse health outcomes than their middle-income counterparts in other rich nations.
To really understand America’s poor health standing globally, epidemiologists like Bezruchka posit, we need to look at those social and economic realities that define our daily lives, what scientists call “the social determinants of health.”
And none of these determinants matter more, these researchers contend, than economic inequality, the divide between the affluent and everyone else. Over 170 studies worldwide have so far linked income inequality to health outcomes. The more unequal a modern society, the studies show, the more unhealthy most everyone in it — and not the poor alone.