Skin is a complex, living organ made up of several structural components that (quite literally) touches a lot of different parts of us. When you look at the makeup, there's collagen, elastin, hyaluronic acid, ceramides, lipids, and so forth; from there, it's also affected by the muscle composition and bone underneath. This is all to say, when wrinkles formit's hardly ever due to a singular reason.

So to start, there is the fact that many components of our skin structure decline with age. "As we age, we lose collagen, fat, and start to resorb bone. These changeslead to volume loss, thin, saggy skin. As a result, our nasolabial folds become more pronounced," says Lolis.

It's also important to note that these lines are exacerbated with movement, the same way crow's feet can come from squinting and the "11's" can come from scrunching yourbrow. "Laugh lines are formed by constant use of the orbicularis orbis muscle which allows us the ability to speak," says Masur. "Over time as we age the skin protecting this muscle becomes stretched creating laxity increasing the appearance of these folds. The region around the mouth known as the peri-oral area is one of the thinnest-skinned on the face, making us more susceptible to fine lines or wrinkles forming the 'laugh lines.'"

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