When you’re young and your skin is chock-full of collagen, these lines tend to fill out rather quickly. However, as your natural collagen levels start to decline, your skin isn’t as able to bounce back from these movements. “Over time, the lines become etched and are present at rest. You have creased the clothing, so to speak, and created ’lip lines,’” adds Westbay. While lip lines do happen naturally as you age, “these lines tend to be particularly prominent in smokers,” says board-certified dermatologist Hadley King, M.D. “They are sometimes called ‘smokers’ lines.’” See, when you smoke, you’re not only constantly puckering your lips but also exposing your skin to free radicals, which can lead to oxidative stress and accelerated skin aging. In other words: You’ll start to see the natural effects of aging (like lip lines) much, much younger. Just know your limits here. The skin around the lips is one of the thinnest regions of your whole face (aside from the delicate under-eyes), which means it may be more sensitive to heavy-duty actives. Retinoids can easily cause irritation in the area, and people often mistake the flakes and tenderness for the average winter chap. Pro tip: Dab an eye cream around the lip area before applying your retinoid, and it will buffer the active without sacrificing its potency. Those UV rays can also dehydrate that delicate skin: “The sun can dry out the lips and compromise the lips’ ability to hold water and hydration,” Michelle Henry, M.D., founder of Skin & Aesthetics Surgery of Manhattan, previously shared with mbg. And as we discussed earlier: Improper hydration can lead to premature skin aging. All the more reason to invest in a moisturizing SPF lip balm. Also: Stop smoking if you currently are. It’s one of the best things you can do for your skin (and your overall health).