It’s summer again, so it’s a good time to talk about sunscreen. Kids and adults should be wearing sunscreen whenever they are outside. Choose a sunscreen that is at least SPF 30, is water resistant, and is labeled “broad spectrum” so it covers UVA rays (cause tanning, skin aging, and wrinkles) and UVB rays (cause sunburns and skin cancer). It takes about 15 minutes for sunscreen to absorb into the skin, so you should apply it before going outside to make sure the skin is protected as soon as it is exposed to the sun. I see lots of kids with sunscreen ON their skin but not rubbed INTO their skin. The sunscreen needs to be absorbed by the skin in order to do its job. Make sure you use enough! Most adults need about as much sunscreen as you can hold in the palm of your hand to cover their bodies. Decrease the amount accordingly for kids. Make sure you cover all exposed areas, including ears, the back of the neck, the hands, and the tops of the feet (I’ve had that sunburn before…ouch!). Lips can be protected by lip balm with at least SPF 15. Remember to reapply sunscreen every 2 hours when out in the sun, after swimming, and after sweating. Sunscreen can be used on babies as young as 6 months (don’t forget that bald, little head!). Younger babies should be protected from the sun with clothing and shade. Eyes can be protected with a hat or sunglasses.
What is SPF?
Sun protection factor, or SPF, is a relative measure of how long a sunscreen will protect against UVB rays. It doesn’t even address UVA rays, which is why you want to use a broad spectrum sunscreen. SPF 15 blocks 93% of UVB rays; SPF 30 blocks nearly 97%; SPF 50 blocks about 98%; and SPF 100 blocks 99% of UVB rays. As you can see, there is a much bigger difference between bare skin and SPF 15 than between SPF 15 and SPF 100. In this case, more SPF isn’t much better, so don’t worry about spending more money to get the highest SPF you can buy. It’s more important to buy a broad spectrum sunscreen, to use enough of it, and to reapply frequently.
Zinc oxide and titanium dioxide both act as physical barriers to UV rays. Unlike past versions of these ingredients that left people with a layer of white all over their bodies, current formulations are micronized and pretty much undetectable. Oxybenzone is an ingredient in a lot of sunscreens that blocks UVA rays and has recently been implicated in bleaching of coral reefs. If you are going to be in the ocean, consider avoiding sunscreens with this ingredient. PABA is an ingredient that has been used to improve the stability of sunscreen ingredients in sunlight. It causes an allergic reaction in about 4% of the population and has been mostly removed from sunscreens. If you are buying sunscreen outside the United States, keep an eye out for this ingredient.
Don’t forget that UVA and UVB rays shine through on cloudy days and in the winter, so sunscreen is important on those days as well. Enjoy the great outdoors and don’t forget the sunscreen!
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A look at some topics in breastfeeding, medicine, and kids health.