In 2008, when many companies reported record declines in sales amidst a global economic recession, L’Oréal, one of the world’s largest cosmetic manufacturers, was somehow immune to the downturn. In fact, L’Oréal enjoyed a sales growth of 5.3% that year—why? Why was L’Oréal the apparent beneficiary of a worldwide economic crisis?

Dating back to the Great Depression, times of recession have consistently yielded anomalous gains for the beauty products industry, even while consumers rein in spending on household goods and recreational products. Journalists have dubbed this curiosity the “lipstick effect.” I recently sought to test the lipstick effect in a series of studies, the results of which were published in the Journal of Personality and Social Psychology. Our findings confirmed that the lipstick effect is not only real, but deeply rooted in women’s mating psychology.

While economic recessions are a recent development in human history, fluctuations in prosperity and resource availability are not. Human ancestors regularly went through cycles of abundance and famine, each of which favorsdifferent reproductive strategies. While periods of abundance favor strategies associated with postponing reproduction in favor of one’s own development (e.g., by pursuing an education), periods of scarcity favor more immediate reproduction. The latter strategy is more successful during times of resource scarcity because it decreases the likelihood that one will perish before having the chance to reproduce.

For women, periods of scarcity also decrease the availability of quality mates, as women’s mate preferences reliably prioritize resource access. This preference stems from the important role that mates’ resources have played in women’s reproductive success. Because economic recessions are associated with higher unemployment and minimal or negative returns on investments, news of a recession may therefore signal to women that financially secure men—those able to invest resources in rearing offspring—are becoming scarce.

Across species, female mate preferences, as well as the effort spent on attracting a suitable mate, are amplified when high-quality males are in short supply, as the reward for discriminating between potential partners is greater. As for the best way to attract males, it’s no secret that you might want to look your best. Selection has favored men who seek in mates qualities related to fertility, such as youth and physical attractiveness. Correspondingly, women’s increased efforts to attract mates most often take the form of enhancing their physical appearance.

Which brings us to lipstick and designer jeans, high-heeled boots and perfume. Would recession cues increase women’s desire to buy these products?

Four separate experiments, along with real-world data, all say yes. Our findings consistently supported the lipstick effect, as college-age women, when primed with news of economic instability, reported an increased desire to buy attractiveness-enhancing goods, along with a decreased desire to purchase goods that do not enhance one’s physical appearance. Our experiments also found that this increased desire for beauty products, clothing and accessories was fully mediated by a heightened preference for mates with resources.

While many journalists who have written about the lipstick effect have theorized that it represents women’s therapeutic spending on cheap indulgences, we found that the lipstick effect applies specifically to products that enhance beauty, even when those products are more expensive. Recession cues increased women’s desire to buy high-end cosmetics and designer clothing, but not to buy budget-line beauty products, which were rated less effective at improving one’s appearance.

Furthermore, we discovered that the lipstick effect and a woman’s desire to attract a mate with resources are unrelated to her independent resource access. Women of both higher and lower socioeconomic status expressed an increased desire to buy luxury beauty products when primed with recession cues. This suggests that an uncertain economic climate leads women to heighten mate attraction effort irrespective of their own resource need.

The national and global economies haven’t been doing well in a long time, and the forecast for recovery appears bleak. Very few industries have done well the past five years—but if there’s one industry that just might be recession-proof, perhaps it’s the one that manufactures our lipstick.