Brief: How does IQ predict vegetarian practices?

Our impression is that it's the smarter people who are more likely to practice vegetarianism to some degree. Go to a blue-collar picnic one weekend and a yuppy dinner party the next, and just ask which one had more vegetarian fare. At the former, we think of hamburgers and hot dogs, while we think of salad and risotto at the latter.

The GSS asks whether you refuse to eat meat for environmental reasons to varying degrees, or if you never abstain for such reasons. I've collapsed responses into refuse to eat meat to any degree (vegetarians) and never refuse to eat meat (omnivores). The pattern doesn't change if we look at the disaggregated data, but this makes the pattern easier to see. The GSS also gives a vocab test to roughly measure IQ. (I've collapsed those who got 0 to 2 words into one group just to keep sample sizes near 100 or greater.) Here is a graph that shows how likely a person is to be vegetarian to any degree depending on what their IQ is (red means veg):


This may shock us at first because vegetarianism almost strictly declines as IQ increases. Maybe we weren't considering representative samples of smarties -- maybe the more liberal or new age tribe among them goes vegetarian, while the conservative or traditional tribe goes for steak. I re-did the analysis looking only at liberals, and again only at conservatives, but the pattern holds up. Nor is there a strong relationship between vegetarianism and either income (meat is more expensive than corn, so that's worth looking at) or education level (this may affect your awareness of the treatment of animals, your exposure to philosophy classes, etc.). Strange as it may seem, there's something unique to smarts that makes you less likely to go veg.

There are the trend-bucking super-smarties, of course, but I'm inclined to believe this is a sort of counter-signaling -- adopting a lower-IQ practice to show that you can still do well even with such a handicap. The very smarts want some way to show that they have the analytical horsepower to have philosophical views on their diet, and at the same time look down their noses at the behavior of their immediate inferiors -- who serve such things as caviar, foie gras, and kobe beef at their parties -- so it's vegetarianism to the rescue!

GSS variables used: nomeat, wordsum, polviews, realinc, educ