The funny thing about fine lines is that you really never know when they’ll actually surface.“I’ve seen women in their 20s start to show fine lines across their forehead because they had a lot of sun exposure. I also have clients in their 40s who’ve been blessed genetically and are just starting to see a few wrinkles,” says Ellen Marmur, M.D., an associate professor of dermatology at The Mount Sinai Medical Center and founder of Marmur Medical in New York City. “It’s about a 50 percent genetics and 50 percent sun exposure split between what causes you to show fine lines and when. They’re equally important,” she says.Obviously, you can’t control how well your genes work (or can you?), but if your mom looks good, chances are you will too at her age…as long as you don’t ruin it with sun exposure. “UV rays convert to heat and basically cook the collagen and elastin in your skin. Those are the proteins that hold your skin up, giving it volume and elasticity. UVB rays penetrate the upper layers of your skin while UVA rays go deeper, so nothing is safe,” explains Dr. Marmur. Once those proteins collapse, your skin folds in on itself, causing the appearance of wrinkles.QUIZ: How Old Does Your Skin Look?No matter how careless you’ve been about sun protection in the past, get religious about it right now to prevent fine lines from worsening. It’s amazing how the skin can actually start to heal itself when it doesn’t have to devote resources to fending off sun damage. Look for a broad spectrum UVA/UVB formula that has SPF 30 or higher as well as antioxidants, which boost the sun protection effects. If you’re going to be doing a lot of sports, sweating or swimming, look for a sweat-resistant, water-resistant formula. And don’t forget to reapply every two hours.In addition to proper sun protection, you can start to lessen the look of fine lines by using an anti-aging cream or serum that’ll rebuild collagen and elastin. Retinoids have long been a gold standard anti-aging ingredient recommended by dermatologists. “The normal cell lifecycle is 28 days, but as you age, your skin doesn’t shed as well and it becomes sluggish. Retinol helps get it back to the 28-day turnover, helping to normalize your skin. It also has pro-collagen benefits,” explains Dr. Marmur. “You don’t need to use the pharmaceutical strength. I actually prefer some over-the-counter formulas because they tend to be a little more forgiving and elegant,” she adds.MORE: Find Your Retinol HereThere are other effective anti-aging ingredients as well. Niacinimide, a form of Vitamin B3, helps maintain the skin’s moisture barrier and increase its natural exfoliation process. Co-enzyme Q10, an essential antioxidant that helps energize cells so they work more effectively, is another good anti-aging ingredient.Just be careful that what you’re using isn’t too harsh for your skin type. “If it’s too intense, it can actually cause your skin to be in a state of inflammation and stress, which produces a wrinkled look,” says Dr. Marmur. If this is your case, nurture your skin back to health with a nourishing oil that contains soothing chamomile and cucumber essence. Once your skin is back to normal, you can reincorporate a gentler anti-aging treatment.One more essential anti-wrinkle skincare step: Start exfoliating one to three times a week. This will also help speed up cell turnover and bring newer, plumper cells to the surface. “If you are just starting to use an exfoliator, look for a creamy, gentle formula. If your skin is older and more resilient, you can try a glycolic pad,” says Dr. Marmur.It takes at least 28 days to start to see results from an anti-aging skincare regimen, which will then gradually accumulate with continued use. “If one chooses only a topical therapy, they can expect mild improvements over months of treatments. But there are several dermatologic treatments using injectables and lasers that dramatically improve the appearance of fine lines immediately,” says cosmetic dermatologist Paul Jarrod Frank, M.D., Director of the 5th Avenue Dermatology Surgery & Laser Center. The first procedures he’d recommend: Belotero or Restylane, both of which are hyaluronic acid fillers that rehydrate your skin and plump up the valleys of fine lines. One treatment costs around $750 and can last for six months or longer.MORE: What the Heck is Hyaluronic Acid?Whatever skincare treatments you chose, be sure to take a holistic approach. Lack of sleep, dehydration and stress make it hard for your skin to function at peak capacity and can also cause or worsen wrinkles. “Make sure you’re drinking enough water, eating healthy food and exercising, all of which help your skin to renew itself,” says Dr. Marmur.