You know how to prepare for most of summer’s beauty challenges. Sunburn? The sunscreen is already slathered. Mosquitoes? The citronella candle’s ready to burn. Frizz? Banished with a DIY beach-hair look. Now what about your teeth?Some of your favorite summer treats might be wreaking havoc and staining your pearly whites. Here’s what you can do to keep your grin looking great.1. Dangerous DrinksAin’t nothin’ says summer quite like a tall glass of lemonade. But mind your sipping—it may be sweet going down, but leaves a sour trail. The acid in citrus fruits can wear away your tooth enamel, making it thinner over time. Eventually, this erosion may even cause visible changes in the shape and texture of your teeth.What’s more, citrusy drinks can dry your mouth out. If you get that puckered-up feeling, it might mean that you’re not producing enough saliva to balance out the pH level and strengthen teeth, says Michael Klein, D.D.S., a prosthodontist in New York City. Klein suggests chasing acidic beverages with water or chewing a stick of sugar-free gum to stimulate those salivary glands.It’s not just drinks to watch out for: Salad dressing often contains vinegar, another acidic attacker.MORE: The Side Effects of Acidic Foods2. Snacks That Stain“Blueberries are rich in antioxidants, but they’re a primary tooth-staining culprit,” warns cosmetic dentist Jeff Golub-Evan. Same goes for blackberries, cherries, pomegranates and other brightly-colored fruits. His rule of thumb: “If it stains a white shirt, it will stain your teeth!”If your cocktails contain these stain-inducing fruits or berries, sip it through a straw to keep from splashing your teeth with every swig. Or Golub-Evans suggests mixing them into smoothies with bananas, yogurt or soy milk to tone down the color. Hot beverages stain worse than cold ones, so stick a straw in an iced tea and enjoy.Quiz: Are You Eating For Your Beauty?3. Gap-FillersAh, sweet summer corn on the cob. And what better way to get corn stuck in your teeth than by gnawing at it row by row? “People think of food in their teeth as just a nuisance,” says Klein, “but it can force teeth to separate and once these spaces grow, you’ll pack more food in there.”Wedged food can lead to tooth decay—not to mention embarrassing summer snapshots. Be sure to floss immediately, so you don’t end up jamming it further up when the next meal rolls around. Some other invasive foods to watch out for: hard seeds and nuts, popcorn, dense meats like steak and that ultimate summer-by-the-seaside indulgence, luscious (but often stringy) lobster.4. Sticky VictualsYou can’t have a BBQ without BBQ sauce, but it’s “a triple whammy,” according to Golub-Evans. “Barbeque sauce is dark, hot and sticky, the worst combination for teeth. Dark colored sauces and condiments stain your teeth and hot staining foods are even worse. And the clincher is that sticky foods attach to teeth.” When you reach for that moist towelette after scarfing down those ribs, remember to clean your teeth, as well. Rinse, floss or steal away for a quick brush.The gooey news continues at night around the campfire. S’mores are a requisite, but the combination of stickiness and sugar does double damage. “Bacteria thrive in an environment that contains sugar,” Klein cautions. It pays to drink water while you’re snacking on the sweet stuff; it only takes two minutes for chocolate to start working away at your teeth!MORE: Sweet News About Chocolate5. Swimmer’s MouthChlorine damages tooth enamel and any bonding work by drying them out and stripping them of essential minerals, says Golub-Evans. Regular swimmers may want to learn to keep their mouths closed in the pool—and the ocean as well, Klein adds. Salt water dries the mouth, slowing the flow of saliva, which contains tooth-boosting calcium and phosphate. A good swish with fresh water helps wash out the chemicals and salt and gets the spit going again.