How to be kind to your skin this summer

Summertime means sunscreen. Here are some ways to be nicer to your skin, according to UNC dermatologist Sarah Corley.

How to be kind to your skin this summer 
June 20, 2018 

Hi friends. It’s summer. You're probably hanging outside more. So here are some things to know if you want to be nice to your skin.

Wear sunscreen every day

I know. The idea of glopping on sunscreen as part of your daily routine doesn’t sound appealing. But the sun emits two types of radiation, ultraviolet B (which causes sunburns) and ultraviolet A (which can disrupt your DNA below the surface of your skin and age your skin faster). Both types are carcinogenic.

Even a 10-15 minute walk in the sun can cause skin damage. Your car’s windshield won’t protect you either. UVA rays can penetrate car window glass, as the left side of this long-time truck driver’s face shows. So even those of us who only enter the great outdoors to drive to work are still vulnerable (sorry). 

Dr. Sarah Corley, a dermatologist with UNC Health Care, recommends a morning dose of sunscreen on face, hands and necks before you enter into the sun-stricken world. Then, before your commute home, she recommends another application of sunscreen or even a sun-blocking powder.

SPF is helpful, but not all sunscreens are created equal

First of all, sun protection factor (SPF) only refers to UVB rays. That’s why it’s important to look for sunscreens that advertise “broad spectrum protection” so you know you’re being protected from both UVB and UVA rays. In terms of UVB rays, SPF measures how much extra protection sunscreen gives you. Wearing sunscreen with an SPF of 30 will allow you to hang in the sun for 30 times longer than you usually would if you weren’t wearing sunscreen.

Using SPF 50 blocks 98 percent of UVB radiation, so using a higher SPF might be overkill. Furthermore, sunscreens claiming to provide high SPF don’t always test well. Consumer Reports found that out of 73 sunscreens, 24 didn’t live up to their SPF claims. Check out their recommendations here. 

Corley said that how you use sunscreen is more important than SPF. You only benefit from a sunscreen’s SPF if you apply the recommended amount. The American Academy of Dermatology recommends two tablespoons (or a shot glass) of sunscreen per person, and more if you’re larger. But it’s doubtful that most people are motivated enough to apply sunscreen that thoroughly. For example, this study shows that participants used only two-thirds to half the recommended amount of sunscreen. We can also be tricked into thinking that just because we used a high SPF, we don’t have to re-apply. But if you're swimming or sweating, sunscreen inevitably rubs off, so re-applying is crucial.

Spray and roll-on sunscreens aren’t as effective as cream

A fine mist of sunscreen doesn’t do the trick, says Corley, unless you thoroughly douse yourself. And if you spray a cloud of sunscreen, you might end up inhaling some of it. As for the sunscreen stick, you have to rub it on several times before getting the advertised amount of protection. But for people who refuse to wear sunscreen, Corley says these weak-sauce methods are better than nothing.

Your tan won’t protect you from long-term damage

Don’t be lulled into thinking that because you have a baseline tan, you’ll be protected from UV radiation. Developing a tan indicates that your skin has been damaged and is trying to defend itself. Depending on your skin type, your skin produces more melanin (dark-colored pigment) to prevent sunburn, but a tan won’t prevent long-term damage like skin cancer. In fact, having a tan is the equivalent of wearing sunscreen with an SPF of only 1.2-2. Which leads us to…

Yes, people with dark skin have more protection. BUT..

Those of African descent can have a natural SPF of up to 13 (compared to most with light complexion’s SPF of 3-4), which helps protect from sunburn, wrinkles and cancers. But it is still possible for black and brown-skinned people to burn and sustain lasting damage to their skin.

Chemical sunscreens work better than mineral sunscreens, but there’s an environmental trade-off

Sunscreen typically works two ways: reflecting or absorbing UV rays. Chemical-based sunscreens absorb UV rays. Mineral-based sunscreens reflect them. According to tests from Consumer Reports, mineral-based sunscreens are generally less effective. This is unfortunate, because common chemicals found in most sunscreens like octinoxate and oxybenzone bleach coral. Some studies show that they can also disrupt hormones in fish and rats. In early May, Hawai’i lawmakers moved to ban sunscreens with oxybenzone. 

The Environmental Working Group has a list of chemical-free sunscreens if you want to avoid harmful chemicals like these.

Stay out of the sun

Here’s something to do if you hate putting on sunscreen: never go outside again. But that’s a sad life. So, Corley recommends hats, umbrellas, rash guards and even these (trendy?) sun sleeves. 

 - Rossie Izlar

Rossie Izlar is the associate producer of Sci Tech Now North Carolina, a weekly show highlighting the latest science stories from North Carolina and across the nation.