Sunscreen 101

May's warming weather gets us thinking of sunny outdoor gatherings, beach trips and pool days — it's the perfect time to observe Melanoma/Skin Cancer Detection and Prevention Month. To get you geared up for safe fun in the sun, GBMC Family Medicine Physician Kevin P. Carter, MD, answers some common questions about sunscreen:

How should I choose an SPF level?
Any SPF between 15-50 is recommended. A sunscreen with at least SPF 15 will block 90% of the sun's harmful rays. With SPF 50, almost all of the dangerous rays will be blocked, but SPFs of 50+ are no more powerful than 50.

Is using makeup that contains an SPF sufficient?
It will be effective, but you can't expect it to work for you all day for the purpose of sun protection, even if it is still working as makeup. When out of the sun, reapply a sunscreen every two hours and allow at least 30 minutes for it to fully absorb into your skin.

What is the difference between physical and chemical sunscreen?
Physical sunscreens put a reflective UV barrier on the skin. The most common physical barriers are zinc oxide and titanium oxide. These can often leave a white-ish cast on the skin. Chemical sunscreens are absorbed into the skin and use chemicals to absorb the UV light, rather than block it. Both are effective; it's a matter of personal preference.

Is it better to use a spray or lotion sunscreen?
Though it may be easier and more convenient to use a spray sunscreen on squirming kids, it is not recommended for small children who can't hold their breath during application. It can irritate their airways if inhaled. Additionally, it can be difficult to tell if you've missed an area. Lotion sunscreen is a good choice because it's easier to tell where you've applied it, and the act of rubbing it in may mean you're being more thorough.

Should I choose a natural/organic sunscreen, or is store brand ok?
The most important thing is to protect your skin from UV rays, so any type of sunscreen is better than none at all. Make sure your sunscreen is labeled "broad spectrum" to ensure it protects against UVA and UVB rays. There has been concern based on animal studies that some of the chemicals used in sunscreens could have harmful effects. More research is still needed to determine if any of the concerns are applicable in humans.

When is it safe to start using sunscreen on babies?
Sunscreen is not recommended for infants under 6 months of age. The best sun protection for babies is a complete lack of sun. If your baby must be outdoors, stay in the shade and make sure he or she is wearing full-coverage clothing made of tightly-wound fibers. Hold the item of clothing up to the sun; if you can see through it, it is not sufficient for sun protection.

What should people with darker skin tones know about sun protection?
Regardless of how dark your skin tone is, you need to safeguard yourself from the sun's dangerous UV rays because of the cancer-causing and aging effects. Use sunscreen and sun-protecting clothing every time you're outside.

Talk to your primary care provider if you have questions about sun safety and preventing skin cancer. If you have a concern about melanoma or possible sun damage, your doctor can refer you to a dermatologist if needed. If you don't already have a primary care physician, visit mygbmcdoctor.com to find one near you.