A chicken and egg question regarding wealth, education, and longevity

i-60ff33c45fe9eefb6e1ae6f3ffd66080-chicken or egg sm.jpg Gina Kolata has an interesting article from Wednesday’s New York Times, discussing education and longevity.

James Smith, a health economist at the RAND Corporation, has heard a variety of hypotheses about what it takes to live a long life — money, lack of stress, a loving family, lots of friends. But he has been a skeptic.

Yes, he says, it is clear that on average some groups in every society live longer than others. The rich live longer than the poor, whites live longer than blacks in the United States. Longevity, in general, is not evenly distributed in the population. But what, he asks, is cause and what is effect? And how can they be disentangled?


The answers, he and others say, have been a surprise. The one social factor that researchers agree is consistently linked to longer lives in every country where it has been studied is education. It is more important than race; it obliterates any effects of income.

Aging and longevity are areas where we have a few tantalizing pieces of information converging from so many different avenues, and yet we really remain clueless about what’s going on. It’s widely accepted that early exposures in childhood play a role in our later health–Kolata asks, how much of a role does our education play in this as well? More after the jump…

As I mention in the title, a link between education and good health/longevity has certainly been established, but it’s not been known which one was the primary cause. Are people healthier–and thus live longer–because they’re wealthy, and able to afford better (and more) education, health care and nutrition? Or are people wealthier because they’re healthier to begin with, and are thus more able to work hard and succeed? One way to investigate this was worked out by a graduate student late last century:

The answer came one day when Dr. Lleras-Muney was reading another economics paper. It indicated that about 100 years ago, different states started passing laws forcing children to go to school for longer periods. She knew what to do.

“The idea was, when a state changed compulsory schooling from, say, six years to seven years, would the people who were forced to go to school for six years live as long as the people the next year who had to go for seven years,” Dr. Lleras-Muney asked.

All she would have to do was to go back and find the laws in the different states and then use data from the census to find out how long people lived before and after the law in each state was changed.

The results:

It turned out that life expectancy at age 35 was extended by as much as one and a half years simply by going to school for one extra year.

This has been replicated in studies examining similar data elsewhere, but it doesn’t answer the question–*why* exactly does more education, independent of other factors, lead to an increased life expectancy? One suggestion is addressed in the story:

Dr. Lleras-Muney and others point to one plausible explanation — as a group, less educated people are less able to plan for the future and to delay gratification. If true, that may, for example, explain the differences in smoking rates between more educated people and less educated ones.

That may sound like a lot of hand-waving, but there are at least some data to support that:

But education, Dr. Smith at RAND finds, may somehow teach people to delay gratification. For example, he reported that in one large federal study of middle-aged people, those with less education were less able to think ahead.

“Most of adherence is unpleasant,” Dr. Smith says. “You have to be willing to do something that is not pleasant now and you have to stay with it and think about the future.”

Certainly years of education do teach people to do things that may be unpleasant now–like study for an exam–for a reward later (like a good grade, or more long-term, a good job, etc.) How much of that translates to health behaviors? I don’t know, and neither, it seems, does anyone else, but it’s certainly a fascinating area of study. Like everything that’s multifactorial, longevity and general health can’t be boiled down to just one factor, but it’s interesting to tease out these various influences and to see where we can intervene, and which interventions will give the most bang for the buck.

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9 Replies to “A chicken and egg question regarding wealth, education, and longevity”

  1. Maybe greater education increases one’s self-esteem and self-confidence and ability to hope. I am dimly — very dimly — remembering a fact about improvements in life span in Europe, that they happened BEFORE improvements in public health. The person I was reading argued that lifespans increased, because people had more hope for the future.

  2. I’ve always wondered if one element in the causal chain is


    The logic is that if you believe in an afterlife then the body is an impermanent, imperfect vessel to begin with. Since a better home awaits beyond, the motivation to take care of yourself is somewhat diminished. On the other hand, if this one life is all we have, then the optimal tactic is to take care of yourself and make your heaven on earth. Contrast the levels of environmental protection, obesity, and smoking in Santa Barbara California vs. Waco Texas.

    Of course, there is also some evidence that folks who are self-described religious live longer, but I wonder if that’s not a sociality effect.

    Its a fascinating topic, longevity, as it arises from such a web of interactions. At the same time, you know there is a correct answer. That’s the curse of the nonbelieving scientist, I suppose. You will never get that debriefing from God when you finally enter the pearly gates. 😉

    Getting things done in Academia
    a guide for graduate students

  3. I’d have to agree that if I learned anything from my PhD, it was delayed gratification. In fact, my gratification was so delayed I still haven’t got it. Huh.

    I think this correlation is only fair: the longer you go to school, the more likely you are to be in some sort of purgatorial graduate program, which isn’t really “living.” It’s more like being in dauer. You deserve some extra time once you get out.

  4. The idea was, when a state changed compulsory schooling from, say, six years to seven years, would the people who were forced to go to school for six years live as long as the people the next year who had to go for seven years

    No state requires grad school. So if grad school had an effect on longevity, the study would not indicate it.

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