Still not wearing your sunscreen? Here are a few good reasons to start: Skin cancer is the most common cancer in the U.S. It’s also the most preventable, says Clinical Associate Professor of Dermatology at NYU and Vice President of the Skin Care Foundation Dr. Elizabeth Hale, since regular use of sunscreen is one of the most effective prevention strategies around. What’s more: 90 percent of skin damage (aka premature skin aging) is caused by UV exposure, says Hale. And (you guessed it) regularly wearing sunscreen is one of the best ways to stave off this wear and tear.
But even if you’re fully committed to wearing sunscreen, good intentions aren’t enough. In order to get the most protection from that bottle, it’s critical you slather right. For those guilty of committing the 10 common sunscreen sins below, remember this: A little extra care will pay off big time in the end.
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10 Worst Sunscreen Slip-Ups
1. You don’t wear it every day.
If you only think to put on sunscreen on beach days or at pool parties, then you’re not wearing it nearly often enough. “Most of the sun damage we get is from cumulative incidental damage,” says Hale. Walking to work (or from work to a coffee shop), driving, even sitting by a window can all add up to cumulative damage over time. Get in the habit of putting on sunscreen every single day in order to have the best chance of staving off skin cancer and signs of aging, says Hale.
“A white T-shirt only offers SPF 7. If it gets wet, that goes down to a measly SPF 3.”
2. You don’t wear enough.
To be adequately covered by sunscreen, a few pats isn’t going to cut it. “Every inch of exposed skin should be covered every single day,” says Hale. A good rule of thumb? If you’re using a lotion-based sunscreen and the goal is to cover exposed skin all over your body, you should use approximately a shot glass’ worth to give yourself a baseline coat. If you’re walking to the office and just looking to cover your neck and arms, a quarter-sized dollop should do the trick. If you’re using a spray, you should see an even sheen all over your skin before rubbing it in.
3. You don’t reapply.
No matter how thoroughly you slather, you’ll still need to put more on if you’re planning to spend several hours outside. “The correct teaching is that you need to reapply sunscreen every two hours,” says Hale. But if you’re swimming or perspiring heavily, you should plan to reapply even more frequently. (Runners, listen up!)
4. You’re using the wrong SPF.
There’s a lot of conflicting information out there about which SPF level provides the right amount of coverage. “The American Academy of Dermatology still says 15 for regular days and 30-plus for pool days,” says Hale. These attitudes are starting to shift a bit, however, and Hale recommends a daily broad-spectrum sunscreen of SPF 30 or higher. But no need to shell out for SPF 100. “Above SPF 30, there’s a negligible difference,” says Hale.
“It’s great if your makeup has SPF, but it’s really not enough.”
5. You don’t know chemical from physical sunscreens.
Fun fact: There are two broad categories for sunscreen and the type you choose will influence when and how it should be applied. Chemical sunscreens work by absorbing the sun’s rays, while physical sunscreens (such as zinc and titanium oxide) work by deflecting them, says Hale. For maximum effectiveness, chemical sunscreens should be applied directly onto the skin (i.e. before applying other body products) 30 minutes before heading outside in order for them to fully absorb into the skin. Physical sunscreens, on the other hand, can be applied over other body products and are effective immediately upon application.
6. You think your clothing’s got you covered.
Just because your skin is covered by a layer of clothes doesn’t necessarily mean it’s protected from sun damage. “Unless you’re wearing sun-protective clothing, regular clothes don’t really afford enough sun protection,” says Hale. For example, a white T-shirt only offers SPF 7. If it gets wet, that goes down to a measly SPF 3. For best protection, always use sunscreen in conjunction with your #OOTD. (It also helps to seek out shade and avoid being outside during peak sunlight hours.)
7. You’re a sunscreen hoarder.
Got the same bottle of sunscreen tucked away in your medicine cabinet or under your car seat since 2013? (Guilty as charged.) While it’s easy to think that you don’t need a new bottle until the old one is done, the reality is a little more complicated. “Most sunscreens are good for up to two years,” says Hale. “But if you keep it in your car or golf bag or another sweaty, hot environment then it destabilizes and the sunscreen is less effective.” A good rule of thumb? If you’re good about keeping sunscreen in a cool, dry place, it should keep for a year or two. But if you ever leave it exposed to the elements, replace it every season, Hale says.
8. You think your makeup’s SPF is sufficient.
“It’s great if your makeup has SPF, but it’s really not enough,” says Hale. For one thing, you might not be applying it with the same amount of coverage on different areas of your face. For another, it’s rarely used on the neck and shoulders. In order to ensure you’re adequately protected, Hale recommends using a moisturizing product with SPF before applying makeup on top.
9. You’ve got OTC interference.
Both over-the-counter and prescription body products or medications can make you more sensitive to the sun, says Hale. And that means you’re more likely to burn. Two common examples are prescription doxycycline (an antibiotic prescribed for acne) and body products containing Retin-A and/or retinol. It’s important to know that these products will make your skin more sensitive to sunlight, says Hale. If you’re committed to using them, be sure to compensate by using a higher SPF (at least 30 or higher) and applying sunscreen more frequently.
10. You rely on 2-in-1 bug repellent/sunscreens.
“[Bug repellent and sunscreen] are very different and should be used very differently,” says Hale. This is especially true because sunscreen needs to be applied much more frequently than bug spray. Hale recommends avoiding combination products and instead applying a base layer of sunscreen before using bug repellent.
The good news: Even if you’re currently committing every sunscreen mistake in the book, it’s never too late to adopt better sunscreen habits. Nail them down now, and you’ll protect your health for years to come.