This is Your Brain on Sexism
Any Questions?
Imagine your brain is an egg. Now crack that egg into a sizzling frying pan of gender inequality. That’s your brain on sexism.
Yes, I’m riffing off the famous 1980’s public service announcements: “This is your brain on drugs.” These commercials were dramatic, fear-based and not particularly effective. But the underlying message was accurate: drugs change your brain. And according to a recent study, sexism appears to do so too.
When women describe how sexism affects them, the response is often, “It’s all in your head.” Well, now they can say, “Yes, it is. It’s literally in my brain.” A groundbreaking study examining over 7,800 brain scans from men and women across 29 countries revealed that women exposed to sexism show real, measurable changes in brain structure.
Specifically, those living in countries with higher gender inequality showed a thinner right hemisphere cortex, particularly within limbic regions responsible for emotional control, resilience and managing stress-related disorders like depression and PTSD. In contrast, women in more gender-equal countries showed no structural thinning, matching or even slightly exceeding male baseline thickness.
What's almost as surprising as the findings themselves is how little attention they've received. The study was published in 2023 in one of the world's most prestigious scientific journals, yet it barely registered in public conversation. Had researchers found that a new supplement, meditation app, or brain-training program altered brain structure, it likely would have generated headlines everywhere. A study suggesting that gender inequality may do the same has largely flown under the radar.
I find these findings both devastating and validating.
They’re devastating because they suggest that gender inequality doesn’t “merely” affect women’s opportunities, paychecks, safety, or political representation. They seem to quietly embed themselves in the architecture of the brain. Sexism not only gets under our skin figuratively, but literally too.
But they’re also validating. They confirm what I have observed in more than twenty-five years of clinical practice and what many women have known all along. For years (forever?), so many of us have been sounding the alarm, often only to be ignored, dismissed, gaslit, or further demeaned.
The findings also reinforce a central argument of my book, Sexism & Sensibility: living in a society that consistently undervalues girls and women is not a benign backdrop to their lives. It has cumulative effects on the body and mind, shaping everything from self-concept and relationships to health, well-being, aspirations, and opportunity.1
We often explain gender differences in health through biology or major traumatic events. But this research points to the very plausible possibility that everyday experiences of sexism matter too.
If something as ordinary as learning a new skill, folding laundry, practicing piano, or shooting baskets can alter neural pathways, why would we assume that a lifetime of being underestimated, objectified, interrupted, scrutinized, harassed, or blamed would leave no trace?
In countries with greater gender inequality2 as measured by things like lower female labor-force participation, less political representation, and fewer opportunities for women, there are often higher levels of the daily indignities that rarely make headlines but shape women's lives: microaggressions, the motherhood penalty, invisible labor, restrictive gender expectations, objectification, sexual harassment, and victim-blaming to name a few.
The constant monitoring, adapting, calculating, and defending that many women must do to remain psychologically and physically safe is a form of chronic stress. And we know that chronic stress affects the brain's ability to adapt, regulate emotion, and thrive (Also: Arnsten, 2009; Lupien et al., 2009).
Importantly, the study found that these brain differences were smaller in more gender-equal countries. They were also less pronounced in men, although men living in highly unequal societies showed some negative effects as well.
From Iceland to India, the pattern was striking: as gender inequality increased, so did the structural differences in men’s and women’s brains. The United States fell somewhere in the middle. While the stress-related thinning observed in women was largely absent in highly egalitarian Scandinavian countries, the same cannot be said for the U.S. where it remained apparent.
Gender inequality is not just a moral issue. It is a public-health issue. A vast body of research confirms that structural gender equality directly predicts better mental health outcomes for women. Women in more equitable relationships also report better mental health and well-being. When we improve gender equality, we don’t just improve fairness—we improve health.
But because appeals to morality and public health alone often fail to move the needle when it comes to women's equality, I feel compelled to talk dollars and cents. Stress, depression, trauma, and poor health outcomes carry real costs—medical bills, lost productivity, disability claims, foreshortened careers—and those costs land on employers, insurers, and taxpayers, and not only on women themselves. Improving gender equality would reduce all of that. And the savings wouldn't stop with women. As I've pointed out elsewhere, patriarchy harms men too, and I suspect part of that harm is psychological: a quiet moral toll exacted by knowingly or unknowingly asking women to absorb the costs of sexism. Guilt, dissonance, and suppressed empathy aren't free—they show up in stress and health outcomes just like any other burden. Equality isn't just the right thing to do; it's a smart investment in our collective well-being.
It’s kind of mind-bending to think about country-level gender inequalities affecting individual brains. The distance between a discriminatory law, a sexist norm, or a wage gap and a woman’s cortex suddenly seems remarkably and uncomfortably small.
We have spent decades asking what drugs, trauma, and disease do to the brain. It's time we asked what sexism does.
Chapter by chapter, Sexism & Sensibility explores the barriers girls and women face in school, relationships, the home, the workplace, public life, and beyond—and the concrete steps we can take, as parents and as a society, to change that reality.
To measure macro-social gender inequality at the country level, Zugman and his team combined the two most widely used national-level gender inequality metrics:
The UN’s Gender Inequality Index (GII): Managed by the United Nations Development Programme, this metric measures disparities across three critical dimensions of human development:
Reproductive Health: Measured by maternal mortality ratios and adolescent birth rates.
Empowerment: Measured by the share of parliamentary seats held by women and higher education attainment rates.
Labor Market: Measured by female versus male labor force participation rates. [1]
The World Economic Forum’s Global Gender Gap Index (GGGI): This index benches gender gaps across four fundamental categories:
Economic Participation and Opportunity: Salaries, participation levels, and access to high-skilled employment.
Educational Attainment: Access to basic and higher-level education.
Health and Survival: Life expectancy and sex ratios at birth.
Political Empowerment: Representation in decision-making structures
