You can slather on as much sunscreen and buy as many anti-aging creams as you want, but how well your skin ages over time might depend on factors beyond your controlโ€”like your blood type. In fact, new research notes that your blood type, of all things, may play a big role in your susceptibility to wrinkles.

In a recent study from the Annals of Dermatology, researchers analyzed the skin of Korean women aged 66 to 84: 29 with type A blood; 26 with type B; 31 with type O; and 13 with type AB. After measuring the wrinkle depth and elasticity around the participantsโ€™ eyes, as well as their skin colorโ€”including their levels ofย melanin, the darkening pigment that causes your skin to tan when exposed to the sunโ€”they found that people with a B blood type produced less melaninย and hadย deeper wrinkle formation. But why?