Absolute versus relative poverty

You often hear how well off the poor are in the US:

Overall, the typical American defined as poor by the government has a car, air conditioning, a refrigerator, a stove, a clothes washer and dryer, and a microwave. He has two color televisions, cable or satellite TV reception, a VCR or DVD player, and a stereo.

Yet this absolute affluence (in the face of relative poverty) doesn't seem to translate into health and well-being. According to a recent commentary in JAMA (no free full text) by Michael Marmot:

blacks in the United States have about 4 times the income of men in Costa Rica or Cuba, but about 9 years’ shorter life expectancy.

The article goes on to demonstrate that simple explanations such as poor diet or sedentary life style don't explain the entire discrepency and that a health effect of status (as opposed to income) exists in every society studied and at every level of status. For example

In egalitarian Sweden, Erikson showed that individuals with a PhD have lower mortality than those with a master’s degree, who have lower mortality than those with a bachelor’s degree, and so on down the educational hierarchy. “Greater poverty,” or material deprivation, is not a helpful answer to the question of why someone with a master’s degree should have higher mortality than someone with a PhD.

While omnipresent, the status effect is more pronounced in some societies (e.g. the United States) than others (Sweden). Marmot proposes some reasons (stress, social participation) but there doesn't seem to be much data backing those up.

Here's a research idea for an enterprising epidemiologist. There seems to be a trend toward US citizens retiring in Mexico, where the cost-of-living is lower. My hypothesis is that the higher social status middle income US retirees in Mexico enjoy should lead to better health and longer lives compared to similar retirees who remain in the US despite similar or decreaseds access to quality medical care in Mexico. Call it status arbitrage.