Cortisol: This stress hormone may also influence us politically, according to recent research by Hibbing and his collaborators. “You can see people’s cortisol levels go up dramatically when you stress them out,” Hibbing says—for instance, by requiring them to prepare to give a speech that is going to be videotaped. “We are finding there are relationships between cortisol and not voting. Those people who don’t vote are the people who tend to have fairly high cortisol levels. Because politics is pretty stressful.”
Testosterone. “There is genetic variance in how much testosterone someone has at birth, and there are certain things that can enhance or diminish that,” explains Brown University political scientist Rose McDermott, a prominent researcher on the science of ideology who authored a recent book chapter on hormones and politics. “One of those things that enhance that is muscle mass—if you build muscle mass, you enhance” your testosterone levels.
What might this have to do with politics? While direct research linking testosterone to ideology is lacking, researchers have recently published data tying muscle mass to political preferences. One study shows that rich men with large biceps are more opposed to wealth redistribution than rich men with small biceps. Another study finds that weightlifting ability correlates with support for, er, a more muscular foreign policy. Plus, get this: Men with wider faces (an indicator of testosterone levels) have been found to be more willing to outwardly express prejudicial beliefs than their thin-faced counterparts.