I’ve been thinking a lot about teeth lately.

First I read this post by Ian Ayres on the value of getting a tooth cleaning.

Then I was out in Salt Lake City to give a lecture at the University of Utah, and the student who drove me around was a very nice guy whose father is a dentist, and we fell to discussing whether dentists’ offspring have better teeth than average (yes, he said), and whether that difference is genetic or behavioral (behavioral, he said).

Then I came across an interesting working paper by Sherry Glied and Matthew Neidell called “The Economic Value of Teeth” (abstract here or download here).

The paper asks whether good teeth improve a person’s labor-market outcome, which is a basic but important question, especially since teeth (unlike height or looks in general) are something that can be fixed.

Glied and Neidell used a clever methodology to measure the impact of teeth on earnings: whether and/or when a certain city’s population had access to fluoridated water. As they explain in the abstract: “The politics surrounding the adoption of water fluoridation by local water districts suggest exposure to fluoride during childhood is exogenous to other factors affecting earnings.”

They found that women who grew up drinking fluoridated water earn about 4 percent more than women who didn’t, although they found no effect for men. “Furthermore,” they write, “the effect is almost exclusively concentrated amongst women from families of low socioeconomic status.”

Knowing what we know about various “beauty premiums,” this strikes me as a not-very-surprising but still interesting result. The one surprise may be that there is no good-teeth effect for men, since the research of Dan Hamermesh (who’s been doing great guest blogging here lately) showed that looks actually matter more for men than for women. To quote a recent Economist article on the subject:

Just over a decade ago Dr. Hamermesh presided over a series of surveys in the United States and Canada which showed that when all other things are taken into account, ugly people earn less than average incomes, while beautiful people earn more than the average. The ugliness “penalty” for men was -9 percent while the beauty premium was +5 percent. For women, perhaps surprisingly considering popular prejudices about the sexes, the effect was less: the ugliness penalty was -6 percent while the beauty premium was +4 percent.

Since then, he has gone on to measure these effects in other places. In China, ugliness is penalized more in women, but beauty is more rewarded. The figures for men in Shanghai are –25 percent and +3 percent; for women they are –31 percent and +10 percent. In Britain, ugly men do worse than ugly women (-18 percent as against -11 percent) but the beauty premium is the same for both (and only +1 percent).

Any way you look at it, the teeth paper is yet another reminder that, as much as we might like to think that wages are perfectly correlated with talent and effort, more trivial factors always come into play.

There is, for instance, the famous argument by three Penn researchers that tall people earn more money than shorter people, although their explanation included the fact that you had to be tall as an adolescent, not the beneficiary of a later growth spurt. Why? Because, their argument went, lifetime self-esteem is heavily formed in adolescence, and you gathered up extra self-esteem if you were a tall adolescent.

Interestingly, that explanation — which always struck me as fascinating, though a bit too fantastic — has recently been challenged in a paper by Anne Case and Christina Paxson called “Stature and Status: Height, Ability, and Labor Market Outcomes” (forthcoming publication in the Journal of Political Economy). Their explanation is brutally simple:

In developed countries, researchers have emphasized factors such as self esteem, social dominance, and discrimination. In this paper, we offer a simpler explanation: On average, taller people earn more because they are smarter. As early as age 3 — before schooling has had a chance to play a role — and throughout childhood, taller children perform significantly better on cognitive tests. … Furthermore, we show that taller adults select into occupations that have higher cognitive skill requirements and lower physical skill demands.

So what does all this research mean if you are a short, not-so-attractive person with bad teeth?

It means you should get your teeth fixed.

This, by the way, is a big part of the reasoning behind the charity Smile Train, which we wrote about here. Smile Train realizes that something as relatively minor as a cleft palate can put a huge drag on your future, especially in developing countries:

Fixing a child’s cleft lip or palate is a relatively cheap procedure with outsize payoffs: cleft children in many countries are ostracized and have a hard time going to school, getting jobs and marrying, and the surgery reverses those disadvantages. Indeed, when pitching a reluctant government, [Brian] Mullaney refers to cleft children as “nonperforming assets” who can soon be returned to the economic mainstream.

If all this talk of beauty premiums and ugly penalties has you down, there’s at least one piece of good news: having a ridiculous first name, be it Fido or Loser or LemonJello, doesn’t seem to affect career earnings at all.

[Note: I’ll be discussing this subject tomorrow (Tues.) morning on The Takeaway.]