July 6, 2017

Uncovering sunscreen safety tips

The best defense against sun damage to your skin is to stay out of the sun, but this isn’t always an option.

If you have an occupation that requires you to be outside or if you enjoy outdoor activities, you will come in contact with the sun and when you do you need to be protected.

Apple A. Bodemer, MD, UW Dermatologist, said if you have to be in the sun, make sure to use a broad spectrum sunscreen. This will protect your skin from damage caused by UVA and UVB radiation found in the sunlight, which can cause skin discoloration, premature aging and skin cancer.

Shopping for sunscreen

When shopping for a sunscreen, Bodemer said to look for an SPF of 30 or greater. You can choose a higher SPF and get a small amount of added protection but regardless of what sunscreen you choose, Bodemer said to reapply every two hours while in the sun. Sunscreen ingredients break down, rub off and lose their effectiveness so reapplying is important.

Also look at what physical and chemical blockers are in the sunscreen. Physical blockers like zinc oxide and titanium dioxide reflect UV radiation away from your skin. The chemical blockers absorb the UV radiation and convert it to heat. Mexoryl and Avobenzone are the two available in the U.S. that protect against both UVA and UVB.

Oxybenzone is an ingredient in some sunscreens that Bodemer says you may want to avoid. It is found to be an endocrine interrupter, which can have adverse effects to the body.

When to apply

If you are planning to go outside for more than 10 minutes, you should apply sunscreen. And it doesn’t matter if it is sunny or cloudy, said Bodemer. The sun’s UV radiation goes through clouds so you should always be protected. Apply sunscreen 30 minutes before going into the sun to allow the ingredients time to disperse evenly on the skin. More frequent applications may be needed if you are swimming or doing a physical activity causing you to sweat, which can wash off the sunscreen.

“If you are wiping sweat off your brow that sunscreen is also being wiped off,” said Bodemer.

Babies and sunscreen

Nearly everyone who will be out during the day should put on sunscreen. One exception are babies 6 months and younger. The best thing to do for infants is to keep them out of the sun altogether,” said Bodemer. “Their skin is much more porous and they absorb more of what we put on their skin than with older children or adults.”

Waterproof sunscreens

Waterproof sunscreens are another option to consider, especially for those times when you are at the pool or active outside.

“It will stay on better if you are an active person who likes biking or running or something where you are getting sweaty,” said Bodemer. But she added, once you wipe yourself dry the sunscreen will move from your skin to the towel so reapplying is important here.

Spray-on sunscreens

Spray-on sunscreens should be used only if a lotion option is not available, said Bodemer. Most of what you are spraying on, she says, goes out into the environment and not on your skin, so it is hard to tell if it is being applied evenly. If you do use a spray-on, spray close to the body and rub it in. Or, spray it on your palm and rub it in.

Sunscreens with bug repellant

Sunscreen-bug repellant mixtures should be avoided, said Bodemer. “Bugs aren’t usually out when the sun is out, so it is a waste. Use products that are good at what they do and not a combination product.”

Other protective options


One fool-proof protection that Bodemer recommends is covering yourself with a wide-brimmed hat and protective clothing. “The great thing about these tools is that they don’t rub off or run off,” she said. Darker colors and tighter weaves will give you more protection than thin or light colors, she said. “One good rule of thumb is if you can hold your shirt up to a light bulb and see light coming through, then UV rays will come through.” She also recommends using UPF-rated garments that are engineered to block UV rays, and most have good ventilation built in.

Shadow rule

Another defense against sun damage is to avoid exposure during the midday, when the sun is highest in the sky. Use the shadow rule, which is to find shade when your shadow is shorter than you are. This gives you an idea of the angle of the UVB rays are coming at you. If they are coming directly at you, you’re not going to have any shadow. And as your shadow gets longer it tells you that the rays are coming at you at a wider angle, so you get some of the benefit of the atmosphere soaking in those UVB rays before they reach you.