Halle Berry. Photo: Gilbert Carrasquillo/Getty Images

If you’ve ever stared at a picture of Halle Berry and wondered how many SK-II masks it takes for her to look exactly the same as her 25-year-old self, you can stop calculating.

A new study from Harvard University, 23andMe, and Olay has suggested a possible explanation that has to do with genes rather than expensive skin care. A team of scientists led by Harvard professor of dermatology Alexa Kimball analyzed data from 231 women* across two ethnic groups (provided by 23andMe) and found that Methuselah genes, or “younger genes” — the ones responsible for characteristics like more-effective DNA repair and the skin’s ability to protect against damaging environmental factors (sunlight, etc.) — are found in one-fifth of black Americans, while only one in ten white Americans is a carrier. The presence of these genes allows some people to look ten years younger than their age, according to the paper.

The study, which will be presented next week at the World Congress of Dermatology in Vancouver, may have provided the science behind the colloquial explanation for why my 63-year-old mother is often mistaken for my older sister: Black don’t crack.

*The article previously misstated the size of the study’s sample.