By John B. Chilton

Contrary to what you might think, people who drive to restaurants are thinner those who walk. But that result is a classic example of an omitted variable. Those who walk are more likely to be poorer and live in neighborhoods that lack an affordable restaurant serving healthy food that is within walking distance. (The thinnest people are those who don't drive and do not have a fast food restaurant nearby.) The study appears in the September issue of the Journal of Urban Health: see this post at the LA Times blog, Booster Shots.

There are similar findings with respect to the availability of grocery stores in poorer neighborhoods -- the poor face lower access to healthy foods, and they pay higher prices. As Daniel Engber observes,

We know, for instance, that the lower your income, the more likely you are to inhabit an "obesogenic" environment. Food options in poor neighborhoods are severely limited: It's a lot easier to find quarter waters and pork rinds on the corner than fresh fruit and vegetables. Low-income workers may also have less time to cook their own meals, less money to join sports clubs, and less opportunity to exercise outdoors.

One thing that gets insufficient attention is that the clearest waste in the American health-care system, if you think of personal choices as part of that system, is primarily at the level of the personal health-care practices: poor eating habits, lack of exercise, smoking, teenage pregnancy, violence. As the economist Greg Mankiw has observed, "For men in their 20s, mortality rates are more than 50 percent higher in the United States than in Canada, but ... accidents and homicides account for most of that gap. Maybe these differences have lessons for traffic laws and gun control, but they teach us nothing about our system of health care." And homicides also teach us lessons about poverty.

We know why we have become less responsible about exercise than our ancestors: the development of labor-saving devices at work and in the home, the automobile, the TV. Less obvious, but also true, we eat less responsibly because the price of food has fallen -- all foods - but especially yummy fatty foods relative to healthy foods. On the plus side, as the result of education, taxes on cigarettes and social pressure, fewer Americans are smokers today than in the past, and we should expect to see this pay dividends in the future.

John Tierney in his Findings column recently presented evidence that the longevity gap between the U.S. and other developed countries reverses if you take account of one major difference: until the 1980s Americans were exceptionally heavy smokers. He quotes medical researchers Samuel H. Preston and Jessica Y. Ho : "The health care system could be performing exceptionally well in identifying and administering treatment for various diseases, but a country could still have poor measured health if personal health-care practices were unusually deleterious."

In a related finding, in a new paper the economist Robert Gordon writes, "A continuing tendency for life expectancy to increase faster among the rich than among the poor reflects the joint impact of education on both economic and health outcomes, some of which are driven by the behavioral choices of the less educated." This could include everything from bad eating habits to teenage pregnancy to gun violence.

Health education in schools is one suggested remedy. And there are various things government might do to create incentives for better individual choices like helmet laws and taxes on sodas, liquor and tobacco. But see this level-headed post on the Food Police -- if we knowingly make bad choices and we bear the consequences, the higher health care costs, what business is it of the government's to intervene; if Americans are especially irresponsible that will make the U.S. look like an outlier in terms of health care costs, but it's not the fault of the health care system per se.

Pooling individuals into insurance exchanges will create a perverse, if perhaps unavoidable incentive towards irresponsible behavior, a perverse incentive that also exists under employer-provided insurance. (It is disingenuous to point out the flaw with the insurance exchanges proposed in current bills working their way through Congress without acknowledging the same is true of employer-provided insurance.) Some of us are lucky enough to have health insurance through our employer. Ultimately the insurance premium the employer pays comes out of our salary. But because I'm pooled with others my premium does not reflect my personal health-care choices which play a substantial, though not exclusive, part in my pre-existing conditions. As a matter of public policy we may not want to penalize those whose pre-existing conditions are beyond their control, but what about those whose pre-existing conditions are?

In short, once you follow the logic full circle, none of us bears the full consequences of our poor personal health-care choices.

If you're like me there's no excuse for not making more responsible personal health-care choices. I'm just taking advantage of the system. I would suggest, however, that some personal health-care practices are not due to freedom of choice so much as they are due to a paucity of options. The poor don't choose to be poor [or do they, in a way?], and many of their options are bad ones. If you can only afford to live in a poor neighborhood what fault is it of yours that your only choices are fast food? Or that you are exposed to more violence? Yes, life expectancy is increasing more slowly among the poor because the poor are more likely to make bad choices due to lack of education, but where is the choice in education if your schools are failing?

Health insurance reform is worthy. But it won't solve a root cause of waste in our health-care system: poverty.

John B. Chilton holds a doctorate in economics from Brown University. He has taught at the University of Western Ontario, the University of South Carolina, and the American University of Sharjah (United Arab Emirates). He resides in Orkney Springs, Virginia, home of Shrine Mont, a Conference Center of the Episcopal Diocese of Virginia. Shrine Mont is the location of the Cathedral Shrine of the Transfiguration. He keeps several blogs.