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.
Oxytocin: Often dubbed the “love hormone” because of its role in forging ties between lovers (and parents and children), oxytocin may also have a role in politics. Paul Zak, a neuroeconomist at Claremont Graduate University, describes research in which a nasal spray containing oxytocin made research subjects more generous in sharing money with one another. But before you jump to the conclusion that oxytocin simply fuels generosity, consider another study, in which the hormone seemed to promote cooperation with your in-group or tribe, but quite the opposite with an outside group or tribe that threatens you. Clearly there are strong political implications here—and not entirely cuddly ones.