Tuesday, March 03, 2009

Health and intelligence correlated at the state level

++Addition++Dr. Bruce G. Charlton points to a paper by Prokosch, Yeo, and Miller showing that body symmetry measurements correlate with scores on three of four g-loaded tests on a study of 78 men, the strongest relationship (r=.39) being with Ravens Matrices. To my relief, hair recession in the temple regions was not one of the ten symmetry measurements used (my right side goes a little higher up my head than the left side does)!


There is a strong relationship between health and intelligence in the US. The United Health Foundation releases an annual report ranking the states based on several health-related factors. These contributing factors have face validity, although there is one peculariaty worth pointing out. The UHF's index page provides five easily digestable graphical representations of conspicuous attributes. The rankings for prevelance of smoking, prevelance of obesity, percentage of children in poverty, and the overall amalgamation all proxy for one another, as seen by clicking on each of these tabs at the UHF page. The South and the Appalachian belt are the least healthy places in the US on a host of measures. But when we jump to the uninsured rate, the concentration shifts markedly to the Southwest, due to the millions of illegal Hispanic immigrants who have no coverage.

The correlation between estimated average IQ by state and UHF's health index is .67* (p=0). The inverse relationship between time preference and intelligence means smarter people are more likely to pass on the junk food, avoid risky behaviors like having unprotected sex or engaging in criminal activity, seek out and set up appointments with specialists for health problems that develop, stick to taking prescriptions and adopting proscribed lifestyle changes, etc.

There is presumably some level of heriditability at play, too. Half Sigma has suggested that the genetics underlying greater intelligence may also be associated with other biological effects that lead to better health.

At the national level, the inverse correlation between IQ and life expectancy is .85, strongly suggesting that this pattern holds globally.

Smart places are livable places. They are more affluent and more egalitarian than duller places are, and they suffer less from social pathologies. In the words of Randall Parker:
Anything that could raise average IQ a few points would do more to boost economic growth and lower social pathologies than increased educational spending or the other typical liberal or free market libertarian nostrums.
Putting into place eugenic incentives--ending low-skilled, illegal immigration and instituting a restrictive merit immigration system based on something like the EB-5 visa program, making the child tax credit progressive with income rather than regressive, sterilization for welfare (well, isn't the argument that because taxpayer funds are keeping big banks afloat Congress should have some say in how they're run? Why not apply that same line of reasoning to our human public charges, too?), showering unmarried mothers and barren high income earners alike in shame (President Obama called out high school dropouts for failing their country, so why not irresponsible single mothers and the cads who knock them up as well?)--will improve quality of life in a slew of ways.

* Hawaii is a major outlier (click on the graph for better resolution), with great health but modest brainpower. Pacific Island nations have average life expectancies in the seventies (with the exception of Vanuatu), despite some endemic health problems like obesity. But the rankings are based in part on the average number of poor mental health days (in Hawaii? That's impossible! Exactly.), health insurance coverage, per capita healthcare spending, and air quality, all of which the archipelago excels in. If the state is removed from the analysis, the correlation jumps to .77. Parenthetically, this is not the first time Hawaii has confounded my probing of the relationship between intelligence and other desirable attributes.


Steve Sailer said...

What's the healthiest state? Colorado? New Hampshire?

Steve Sailer said...

Hawaii attracts affluent outdoors people, trustfunders who like to surf.

Anonymous said...

It still seems odd that Hawaii's "brainpower" is rather modest. Aren't most of the groups in its population noted for being generally high-IQ?


agnostic said...

Hybrid vigor against disease among the mixed Hawaiians?

Audacious Epigone said...


Vermont is #1, Colorado is #2, and New Hampshire is #3. Well done.


Native Hawaiian Islanders don't do well. But what I've wanted an explanation for is why Hawaii's white kids fare so poorly on NAEP tests. The only state whose whites do worse is... West Virginia. Since the cost of living is so high on the islands, I'd think that'd 'select' for pretty affluent people with smart kids. But apparently I'm wrong on that.

Anonymous said...

I live in Atlanta and when I went to my brother's graduation at Dartmouth, my goodness, how thin everyone looked!