In the jittery world of anxiety research, one of the field's most consistent findings is also perhaps its biggest source of controversy: Women, according to countless studies, are twice as prone to anxiety as men. When pollsters call women up, they always confess to far higher levels of worry than men about everything from crime to the economy. Psychologists diagnose women with anxiety disorders two times as often as men, and research confirms—perhaps unsurprisingly—that women are significantly more inclined toward negative emotion, self-criticism, and endless rumination about problems. From statistics like these, some have even leapt to the Larry Summers-esque claim that women are simply built to be much more nervous than men—an idea that has outraged many women inside (and outside) the psychology community.
According to new evidence, however, the outraged are right: When it comes to our preconceived notions about women and anxiety, women are unfairly being dragged through the mud. While women are indeed more fretful than men on average right now, this difference is mostly the result of a cultural setup—one in which major social and parenting biases lead to girls becoming needlessly nervous adults. In reality, the idea that women are "naturally" twice as anxious as men is nothing more than a pernicious illusion.
Before we can unleash the vengeance of the furies on this falsehood, though, there's some bad news we need to get out of the way first: a few recent studies have indicated that the hormonal differences between the sexes really do make women a touch more biologically inclined toward anxiety than men. One noteworthy experiment from last year, for example, found that female brains—well, female rat brains—get more rattled by small levels of a major stress hormone called corticotrophin-releasing factor than male brains. Another 2010 study, at Florida State University, likewise revealed that male rats' higher testosterone levels seem to give them a larger buffer against anxiety than female rats have. (Don't get hung up on the fact that these studies were on rodents; most of what we know about the neuroscience of fear actually comes from tormenting lab rats.) Just how big a role these biological factors play in human women's anxiety isn't yet clear.
But one thing we do know for certain is that the way we raise children plays a huge role in determining how disposed toward anxiety they are later in life, and thus the difference in the way we treat boys and girls explains a lot about the heightened nerves we see in many adult women. To show just how important this is, let's start at the very beginning. If women really were fated to be significantly more anxious than men, we would expect them to start showing this nervousness at a very young age, right? Yet precisely the opposite is true: According to the UCLA anxiety expert Michelle Craske, in the first few months of infants' lives, it's boys who show greater emotional neediness. While girls become slightly more prone to negative feelings than boys at two years (which, coincidentally, is the age at which kids begin learning gender roles), research has shown that up until age 11, girls and boys are equally likely to develop an anxiety disorder. By age 15, however, girls are six times more likely to have one than boys are.
Why the sudden gap in diagnosed anxiety? Well, one answer is that as a flood of adolescent hormones sends these boys' and girls' emotions into overdrive, the difference in their upbringings finally catches up with them. After all, whether parents intend to or not, they usually treat the emotional outbursts of girls far differently than those of boys. "From a socialization angle, there's quite a lot of evidence that little girls who exhibit shyness or anxiety are reinforced for it, whereas little boys who exhibit that behavior might even be punished for it," Craske told me.
In my book Nerve, I call this the "skinned knee effect": Parents coddle girls who cry after a painful scrape but tell boys to suck it up, and this formative link between emotional outbu