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5 Things To Know Before You Buy Sunscreen

Beachgoers bask in the sun, July 3, 2018.
KPBS Staff
Beachgoers bask in the sun, July 3, 2018.
5 Things To Know Before You Buy Sunscreen
5 Things To Know Before You Buy Sunscreen GUEST: Dr. Robert Dorschner, dermatologist, UC San Diego Health

I'm Maureen Cavanaugh Sandy Agins no sunscreen is an essential part of outdoor gear. But if your sunscreen isn't working it may not be the products fault. Doctors say many if not most people don't apply sunscreen correctly or often enough. And on top of that the chemicals in some of the most popular products are coming under fire for being bad for the environment. Joining me is UC San Diego dermatologist Dr. Robert Dorsch there. Doctor welcome to the program. Thank you for having me. Now when you go to the sunscreen aisle and at the grocery store there are so many sunscreen options these days lotions sprays powders physical sunscreens chemical sunscreens. What do you tell your patients about what they should look for in a sunscreen. Well really when it comes down to the most important thing is getting a sunscreen that you can put on and it doesn't do you any good if it's still in the bottle. So there's a lot of different types of formulations that people can choose from depending on what's going to be best for them. But the most important things are that you get a sunscreen that has broad spectrum coverage. That means that it covers both UVA and UVB rays. Two different types of sunlight that can damage the skin. You also want a product that has an SPF or sun protection factor of 30 or better. And then we also recommend that you get one that is water resistant. This helps you stay out a little bit better if you're sweaty or are being active. You said 30 or better for the SPF or sun protection factor. Does a higher SPF mean you're actually getting more protection. So yes it does. But there are diminishing returns. So an SPF of 15 blocks about 93 percent of the race whereas an SPF of 30 blocks about 97 percent of the Rays. However one thing that's important to keep in mind is when they study these and kind of give the the SPF ratings they do are under control circumstances with a certain amount of product almost nobody in real life puts on a nuff sunscreen. So the nice thing about having a higher SPF is that you have put on less product than the recommended seal may be getting good coverage. How often should people be applying sunscreen so no sunscreen last longer than about two hours. So everybody really needs to be back on every two hours and that's the same whether it's an SPF of 30 or an SPF of 100. That really doesn't make any difference in how long it lasts. Now if you're sweating a lot or if you're going in the water then it lasts considerably less and you probably need to reapply every 40 minutes to 18 minutes depending on the product and it should say on the bottle. What about those moisturizers and other products that contain SPF. I've read that they may not be as effective against sun damage compared to traditional sunscreen. Do you know why that might be. So those products are great. They contain sunscreen ingredients that are easy to put on putting your moisturizer on the morning or not the kind of the same thing as your regular sunscreen lotion that you use at the beach. They need to be reapplied in order for the sun protectant to actually be working. So unless you're reapplying your lotion every two hours and you're going to lose the benefit of the SPF in it. And what about the way people use sunscreen especially sprays people just sometimes I think they just spray it on and then then go. Is that effective. The sprays are really wonderful for getting on easily especially if you have kids that are moving quickly on the beach. But the measure of the fact is that you really need to measure how you get an adequate amount of the spray on the skin. And most of them require that you actually rub it in even after you do spray Don. So check the instructions on the bottle if done correctly then they are just as effective as a lotion. Now I mentioned there are physical and chemical sunscreens what's the main difference. It's the main differences kind of the strategy that they employ the ingredients employed basically block the sun for you. So the chemicals sunscreens the ingredients in them act like a sponge. They absorb the sun's rays and stop the sun from damaging your skin in that way. The physical sunscreens use the mineral so zinc oxide or titanium dioxide to basically make a little shield over your skin that deflects the sun's rays and protects you in that way is an easy way to think about this if you're using a physical sunscreen you're probably gonna see it on you. But if you're using a chemical sunscreen it'll probably absorb into the skin. So that is true. And actually most people may remember pictures of lifeguards back in the day with a weight pisti zinc paste on there. Their news is modern sunscreens that use these physical blockers are much more elegant but they still are more likely to leave a little bit more of a weight or washed out appearance than the chemical sunscreens. Now speaking of the chemical sunscreens recently Hawaii banned sunscreens with two chemicals in them because it's believed they contribute to the destruction of coral reefs. How widespread are these ingredients that were banned and are used in sunscreens. So the two ingredients that Hawaii has banned are oxybenzone and octa Knoxy. That are quite a number of sunscreens oxybenzone is a really good wide broad spectrum ingredient that's in probably almost two thirds of chemicals sunscreens. So it is fairly widespread. So are there some environmentally friendly alternatives. Probably the best most environmentally friendly ingredients that we have are the physical blockers that we were just talking about. So zinc oxide and titanium dioxide these are a naturally occurring minerals. There have not been shown to have any environmental effect. And as far as health effects do they stay in the top layers of the skin to deflect the sun and don't even absorb into the body. So there are wonderful ones for people to look for when considering it more environmentally friendly sunscreen. So we've been talking about the many sunscreen options there off for people and because of that. You'd think there'd be something out there for everybody. And yet melanoma rates have been on the rise. Do you know what's behind that. There may be a number of factors that are involved in that when it has really come to light over the last several years and is getting more attention as the use of indoor tanning beds which are really associated with the increasing rates of melanoma among young people. And there has been a lot of moves afoot to kind of either reduce or restrict the availability of these beds to minors. But it's important that people try to avoid these because there is a pretty strong link between these types of UV lights using the tanning beds and melanoma. So if you go outdoors aside from sunscreen what are some other recommendations to protect your skin from the sun. Yes so when you're outdoors that a couple of other things that we strongly recommend would be to seek shade out first of all and then also use a sun protective clothing such as hats or sunglasses long sleeves et cetera. So it's interesting is there's a study that indicated that people wearing sunscreen may actually be more at risk of being sunburn in some cases than people who are not wearing sunscreen. And this has been largely attributed to the fact that people falsely felt that they were protected adequately from the sun just by wearing the sunscreen and didn't take advantage of other opportunities to protect themselves such as shade or clothing. They may have stayed out in the sun too long or they failed to reapply their sunscreen. So really a combination of things that include seeking out shade wearing protective clothing as well as sunscreen to protect yourself. I've been speaking with UC San Diego dermatologist Dr. Robert doorstopper. Doctor thank you. Thank you for the opportunity. Maureen.

San Diegans know that sunscreen is an essential part of outdoor gear. But if your sunscreen isn’t working, it may not be the product’s fault.

Doctors say many, if not most people don’t apply sunscreen correctly or often enough. Also, the chemicals in some of the most popular sunscreen products are coming under fire because they may be harmful to the environment.

Dr. Robert Dorschner, a dermatologist with UC San Diego Health, discusses the latest sunscreen recommendations from the American Academy of Dermatology, Wednesday on Midday Edition.


Below are Dorschner's responses to some sunscreen basics.

Q: What should consumers look for in a sunscreen?

A: The three main things that people should be looking for in their sunscreen are an SPF of 30 or greater, broad spectrum protection and water resistance. The American Academy of Dermatology recommends an SPF of 30 or more to make sure your sunscreen is blocking enough of the ultraviolet (UV) rays that cause sunburns, aging and skin cancer. A broad spectrum sunscreen will protect you from more of the UV rays from the sun (UVA and UVB). In addition to these important considerations, it is equally important that you get a product that you are able to use regularly. All sunscreen must be reapplied every 2 hours, and more often if you are in the water or sweating a lot. Sunscreens rub off and the ingredients that protect you from the sun break down as they do their job. That's why you need to re-apply.

Q: Does a higher SPF protect your skin better?

A: The SPF rating is a measure of how much UV the sunscreen blocks. The higher the rating, the more it blocks. For example, an SPF of 15 blocks about 93 percent of the UV rays, while an SPF of 30 blocks about 97 percent. A higher SPF does block more of the rays, but over an SPF of 30, some people say there are diminishing returns. However, the SPF ratings are based on standardized tests that apply more sunscreen that the typical person actually uses in real life. For this reason, I often recommend higher SPF products because even if you don't slather on the recommended amount (1 ounce), you may still get enough protection. And, everyone should keep in mind that even good use of sunscreen is not enough on its own to prevent sun damage. Everyone should be seeking shade through the day and using sun protective clothing like hats and sunglasses.


Q: Are spray sunscreens as effective against skin damage and sunburn as non-spray sunscreens?

A: Spray sunscreens also provide good protection, so long as you get one with an SPF over 30 and Broad Spectrum coverage. A sunscreen is only going to be effective if you use it. It can be very hard to get sunscreen on kids. Some people don't care for the feel of lotions. Sprays can be just as effective as lotion sunscreens. Some important things to keep in mind, though: most sprays need to be rubbed in after being sprayed on - and make sure you spray on enough, be careful not to inhale the spray, to apply a spray sunscreen to the face, I recommend spraying it onto your hand and then rubbing it on.

Q: What are some environmentally-friendly sunscreens?

A: Probably the most environmentally-friendly ingredients are the physical blockers, zinc oxide and titanium dioxide. These are naturally occurring minerals, they have not been shown to have any environmental effect. In terms of health effects, they stay on the top layer of the skin to deflect the sun and don't even absorb into the body. So, they are wonderful ones for people to look for when considering a more environmentally-friendly sunscreen.

Q: Do sunscreens expire?

A: Sunscreens do expire. Most should have a date stamped on the bottle. The ingredients can break down over time in the bottle. After the expiration date, the sunscreen may not provide as much SPF as it should. If in doubt, its probably best to get a new bottle of sunscreen - it will probably be cheaper and less painful that treating a sunburn.