Post written by Maureen Caro, FNP-BC, Family Nurse Practitioner
The first thing to understand is why we should protect ourselves from the sun. The radiation from the sun is responsible for skin cancer, premature aging and burning.
There are two types of UV radiation that are of interest here—UVA and UVB.
A helpful way to remember the difference is UVA causes Aging, and UVB causes Burning.
UVA has a longer wavelength. It will go through clouds and glass, so if it seems you are protected on a cloudy day or behind your car’s windshield, incorrect! UVA is responsible for damaging cells’ DNA and causing cancer, as well as wrinkles and aging. Tanning is your skin trying to protect itself from UVA by releasing melanin, a dark protein that absorbs the radiation. African-American skin is already supplied with melanin. Even well-tanned skin is not very protective against damage. UVA rays are used in sun tanning beds.
The other UV ray is UVB. UVB does not go through clouds and glass and is what the body uses to make vitamin D. Next time someone tries to sell you on a tanning bed by saying that it will protect you against burning and help you make vitamin D, now you know that isn’t true! I also do not recommend tanning beds because they greatly increase your risk of dangerous skin cancers. There are three major types of skin cancer—basal cell carcinoma, squamous cell carcinoma and malignant melanoma. Malignant melanoma is the scary one, and the one I never want to miss! It is rapidly spreading and very dangerous. If you have a mole or a change in skin always contact your provider immediately.
Types of Sunscreens
There are two types of sunscreens available in the United States (US), usually differentiated between mineral (zinc oxide and titanium oxide) and chemical. Zinc and titanium oxide are white metals that reflect the radiation back. However, they are also what we use to make white paint for artists, so they tend to make you look ghostly. If you rub it in well, this can be managed but not eliminated entirely. Chemical (or organic) sunscreens absorb the UVB radiation. Two of them have been implicated in damaging coral reefs, oxybenzone and octinoxate. Anything you wash off your skin will go in the sea eventually, so I prefer to avoid these and especially recommend not taking them for anyone planning a beach vacation.
Now on to the fun part—FDA regulations! SPF is how we measure sunscreen power in the US, and this stands for sun protection factor. It is measured by applying the sunscreen to a square inch of skin in a non-sun-exposed area (buttock) of a hopefully well-paid volunteer and then comparing it to an unprotected square inch on the opposite buttock on the same volunteer. Reddening/burning of the skin is measured, and then the poor person is mercifully released. SPF is a multiplication factor in how much more sun exposure it takes to burn in comparison to the unprotected skin. SPF 15 does not mean 15 minutes, it means 15 times more solar energy exposure to start to burn. This is not a direct correlation to time spent out in the sun. The amount of solar energy outside varies depending on what time of day it is and where you are on the globe. I usually encourage people to use SPF 15 or higher, and to reapply every two hours. You have to wait about 15 minutes after application to have it dry down and become fully effective. The other thing you want to look for on the packaging is broad-spectrum. UVB is the ray responsible for burning, and if we are measuring burning to get to a SPF classification then we are missing out on UVA entirely. Now, if you look for the words broad-spectrum, that will give you UVA protection.
Gel? Spray? Cream? Mist?
The other big thing is what kind you use. Gel? Spray? Cream? Mist? One of my nursing professors used to say, “It only works if you use it.” Find a formulation that you will use effectively. I personally keep tiny bottles of gel face sunscreen next to my front door, in my purse, in my car and in my office. I always forget to apply sunscreen until I am about to step outside. I keep spray cans in the kids’ swimsuit bags, since they refuse to sit still long enough for me to patiently rub in a cream. I don’t see mists getting a thick enough application to really work. Whatever you can get in the highest SPF of at least 15, with the least amount of perfume, can reapply every two hours, and don’t dislike—do that! Don’t forget the tricks my granny’s generation had, wide-brimmed hats and light-colored clothes with a tight weave will also protect against sun. Thank you and enjoy the sunshine responsibly!
Maureen Caro is a family nurse practitioner and is accepting new patients. To schedule call 913-648-2266.