In addition to leaving the house sans sunscreen and popping your pimples.
Don't: Use In-Office-Strength Chemical Peels at Home
Why it's really that bad: Unlike the ones you find at reputable cosmetics outlets that are specifically designed for home use, "Extremely strong peels you might buy from websites you don't know very well can do serious damage to your skin," says Sejal Shah, MD, a board-certified dermatologist in New York. "I've seen women end up with chemical burns, which are not only painful but lead to scarring and dark marks."
The fix: Be wary of peels that use language like "office-strength" on the label. Better yet, run any potential peels past your dermatologist before using, or ask for recommendations based on your skin type.
Don't: Go DIY With Sunscreen
Photo: JGI/Jamie Grill/Getty Images
Why it's really that bad: Serious sunburns, anyone? "Homemade sunscreen is the single worst thing I've ever seen someone do to their face," Shah says. "It can be disastrous." People may do it because they're worried about chemicals found in store-bought sunscreens, and DIY versions often include some form of the physical UV blocker zinc oxide. If you're thinking, But zinc oxide is a common ingredient in non-chemical sunscreens, so what's the big deal?, here's the problem: "Without FDA testing and approval, you have no idea what level of protection you're getting," Shah says. Ingredients in FDA-approved sunscreens are "generally recognized as safe and effective." The FDA also vets whether a sunscreen protects against both UVA and UVB rays to offer broad-spectrum protection and verifies its water-resistance level.
The fix: There are plenty of safe, effective and well-tested products to choose from, both physical and chemical. Try one of the best new options listed here.
Don't: Try More than 1 New Skincare Product at a Time
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Why it's really that bad: The more unfamiliar ingredients and products there are on your face at once, the higher the likelihood that your skin won't play well with one of them. "And if you have a reaction, you won't know which product caused it," says Doris Day, a clinical associate professor of dermatology at NYU Langone Medical Center, in New York.
The fix: Don't try to overhaul your entire skincare regimen in one go. Limit new products to 1 per day.
Don't: Over-Exfoliate, Over-Cleanse, Over-Apply
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Why it's really that bad: Both dermatologists we spoke to have seen patient after patient who assumes that if a little is good, more is undoubtedly better: Women who wash their face 4 times a day, exfoliate in the morning and at night, pile on 4 wrinkle fighters or blow right by the "apply a thin layer" direction on acne spot treatments and lay them on thick. "The only thing you're going to accomplish is drying out and irritating the skin and making whatever problem you were trying to solve worse," Day says.
The fix: Best results come from following the directions on the product. If you're doing that but still not getting what you want from your current regimen, ask your dermatologist how you can safely improve it.
Don't: Make These 2 Mistakes With Glasses
Photo: altrendo images/Getty Images
1. Forgetting to clean them before wearing Why it's really that bad: Just like your smartphone, your glasses can accumulate oil, bacteria, dirt and grime, especially on the nosepiece and sides that make contact with your skin, potentially causing breakouts and skin irritation. The fix: Every day, run your glasses under warm water, add a drop or two of liquid dish soap (helpful for getting grease off of lenses and frames), says Karen Gladstone, OD, an optometrist at Arrigg Eye and Ear Associates in Lawrence, Massachusetts, wash the glasses, then dry them with a soft cotton or microfiber cloth.
2. Procrastinating on getting them Why it's really that bad: Over time, habitual squinting can lead to wrinkles around the eyes and an aged appearance, says Shah. The fix: If you have to squint to see things that used to be clear as day, make an appointment with your eye doctor and get yourself some specs.
The Skin Saboteur Hiding In Plain Sight At Every Backyard BBQ
Heating meat at high temperatures produces a chemical reaction between the fat and protein that results in compounds called "<a href="http://circ.ahajournals.org/content/114/6/597.full" target="_blank">advanced glycation end products</a>" (AGES). These AGES are aptly named, says Dattner, because they're linked to oxidative stress and inflammation that can make your skin look ruddier, duller and more wrinkled -- older, in general. (<a href="http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3704564/" target="_blank">AGES can also increase your risk of diabetes and cardiovascular disease.</a>) These compounds are found in French fries, potato chips, deep-fried chicken and other foods that have been cooked in oil at extremely high temperatures. What's more, Dattner says, is that <a href="http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0075003" target="_blank">AGES can interact with UV rays and wreak havoc on the skin</a>.
<strong>Try this:</strong> You don't need to go on a raw-food diet, but it might not be a bad idea to eat grilled foods in moderation (deep-fried, too, but you knew that).