Political scientists are starting to find that the angry, threatened, gun-clinging Republican stereotype might run deeper than the news. To cite just a few recent studies, in 2006 John T. Jost found that conservatives suffer from “chronically elevated levels of threat” and are “more likely than liberals to perceive the world as a dangerous place,” while in 2014 John R. Hibbing found that “conservatives tend to register greater physiological responses to negative stimuli.” The link works the other way, too. Heightened insecurity seems to increases the popularity of conservatism, as seen in its rise in the U.S. after 9/11. Why are Republicans so afraid? Dietary differences and the hormone cortisol may provide an answer.
Most political scientists look to environmental factors like parental influence, socioeconomic background or socialization to explain psychological differences. But an avalanche of new studies has found genetic and physiological differences may be key. For instance, monozygotic twins (who look the same) separated at birth and raised in completely different environments have stunningly similar ideological leanings, and fMRI scans have found that Republicans and Democrats use different parts of their brains when facing risk. In fact, just this month a study published in the American Journal of Political Science — one of the field’s leading journals — explains why people marry “within the party” — liberals and conservatives smell different and we are attracted to people who vote like us!
Back to the question. Why do Republicans have higher levels of threat perception? Chris Calkins ’15, Zach Queen ’15, Jake Becker ’15 and I are taking a stab at it. Our theory revolves around the hormone cortisol, which is released by the body in response to threat. It increases the amount of sugar in the blood stream for the fight-or-flight response. If Republicans have chronically higher levels of threat perception, it seems reasonable to assume that they must have higher basal cortisol levels. While Jeffrey A. French’s 2014 study has found lower voter turnout in people with high basal cortisol levels, no study has looked at differences in the stress hormone across political ideologies. To find out, the four of us are going to take saliva samples from a hundred Republicans and Democrats. We expect to find that Republicans have higher cortisol levels than Democrats.
This is where food comes in. The fascinating thing about cortisol is that it creates a sugar craving (it increases the amount of glucose in the blood stream for our fight-or-flight response). If conservatives have higher cortisol (or stress) levels, they must also experience more sugar cravings. One can thus hypothesize that there are differences in conservative and liberal diets, with conservatives eating more carbohydrates. We are thus also administering surveys to see if this is true.
The link between diet and cortisol runs the other way, too. Sugar consumption increases cortisol levels. Republicans eat more cortisol-increasing foods because they are more stressed, but could the same foods then increase stress and, with it, conservatism?
One of the puzzles of public opinion research is the remarkable consistency in a person’s ideology. As people age, many things change, but political ideology is surprisingly consistent. It could be that the food we eat, an everyday determinant of cortisol levels, explains this consistency. So Republicans may eat more sugar because of higher cortisol levels — but could these foods, in turn, be keeping them conservative? As for Democrats, are our diets richer in cortisol-lowering foods and/or poorer in foods that increase it? Do ideological shifts show up on a person’s plate, or could dietary change induce ideological shifts?
Biopolitics has opened a whole new frontier in political science, but it has been met with a lot of resistance. We like to think that we can make thoughtful and considered choices — the idea that a gene or diet or hormone has largely made those choices for us is disturbing. When genes and physiology are added to the mix of known determinants like parental influence, race and income, the way you vote may have very little to do with choice. Given the deplorable state of politics today, if our hypothesis is true, I for one am going to breathe a sigh of relief.
Abhishek Parajuli '15 is a contributing columnist.
Correction appended: October 14, 2014
A previous version of the column included a misspelling of the last names of Chris Calkins ’15and Jake Becker ’15. It has been revised to correct the error.
