White bread, bagels, popcorn…
“Foods with a high glycemic index give you a sugar rush that will be terrible for your skin,” says Ava Shamban, an assistant clinical professor of dermatology at UCLA. “When you increase sugar levels in the bloodstream, the sugar that’s not picked up by the liver can get into your collagen, which your body may then identify as damaged goods and chew up. It can also cause inflammation that could make you break out.” You can find out a food’s glycemic index at glycemicindex.com —anything under 55 is considered low.
Red velvet cupcakes, pistachio ice cream cones…
Sweet stuff that’s irritating on your Instagram feed—looking at you, artfully arranged plate of macarons—is even worse for your skin. Once again, too much sugar can break down collagen and elastin, making your skin look dull and causing wrinkles over time. When you can substitute for sugar, “honey is the best sweetener since it’s loaded with antioxidants,” says Shamban.
Dairy gets a lot of flak for being bad for your skin, but the truth is “we don’t have enough data to know for sure, so we can only say it’s a potential culprit,” says Shamban. So far, studies have shown a correlation between dairy and acne but not causation, and anecdotal evidence is less reliable than you’d think. “If you gave up eating yogurt or drinking skim milk every day and had fewer breakouts, you wouldn’t know if it were because of the dairy or its sugar content,” says Shamban. Your best bet is to look for dairy that’s made a) without added sugars and b) from cows that are not treated with hormones. “The hormones cows are fed can be steroid analogues, which can make you break out,” she says.
“The BPA in water bottles is another steroid analogue, which means it could act like hormones in your body,” says Shamban. “You don’t think about your bottled water breaking you out, but we don’t know yet—and anyway, there are a thousand reasons not to use plastic bottles all the time.”
Your morning coffee
If it gets you out of bed, don’t give it up. But you’d be wise to balance your coffee or fancy-pants espresso by chugging a glass of water, too. “Coffee acts as a diuretic, and that won’t make skin pretty, that’s for sure,” says Shamban. “Our skin cells are made of water, and anytime they shrivel up, you lose that glow and plumpness.” That means fine lines, like the ones we all have around our eyes, look worse. But as long as you add back hydration, there are plenty of benefits to drinking coffee, too: The polyphenols in coffee could mean younger-looking skin in the long run. Women who drank about three cups a day had the fewest age spots in a study in the International Journal of Dermatology.
Rounds of margaritas…
If you’ve ever had a hangover, you already know that having more than a few drinks dries out your skin the next day—it’s why lines look worse (like, way worse) on Sunday morning. Pile on the moisturizer and, if you’re lucky enough to look puffy, too, try pressing a compress with half-and-half or whole milk under your eyes. The proteins in whole-fat milk bring down bags.
…And the salt on the margarita rim (or in a bag of chips)
“Just as coffee and alcohol do, too much salt will dehydrate your skin,” says Shamban. It’s why some dermatologists go to extremes: “I put all of my patients on a zero-added-salt diet—if you’re making chicken, you can cook it with rosemary, thyme, and pepper, no salt. Fish is olive oil, garlic, and basil. And restaurants function on salt, so I tell them no dressings, sauces, or salt,” says Harold Lancer, a dermatologist in Beverly Hills.
Milk chocolate—but not dark chocolate (woo-hoo!)
It’s the sugars that make milk chocolate hard on your skin, but for the record: “There’s no reason to skip dark chocolate,” says Shamban. (Look for 70 percent cacao or higher.)
If you have rosacea, don’t pour hot sauce on your pizza. “It’s the skin condition that’s most sensitive to food,” says Shamban. “And spicy foods trigger inflammation and flushing.”
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