We’re dropping some SPF knowledge, courtesy of Dr. Jacobs. All of this info can be found in her book, Live Life Beautifully (With a Little Help). We all want to do what’s best for our skin and protecting it from the sun is the #1 thing you can do. Sunscreen labels can be confusing, so let’s break it down.
1: Broad Spectrum
Exposure to UV (ultraviolet) rays can lead to DNA damage in your skin cells, and this damage can lead to skin cancer. There are two types of UV radiation you want to protect yourself from: UVA and UVB. UVA rays penetrate deep into the skin and may lead to premature skin aging and cancer. UVB rays are responsible for the color change in your skin after spending time outdoors – your tan or sunburn is a direct result of UVB rays. Think UVA equals aging and UVB equals burning. “Broad spectrum” means that the sunscreen is providing protection from both UVA and UVB. But is that enough? Shouldn’t the question be how much protection are you getting?
2: Sun Protection Factor (SPF)
The SPF value indicates the level of sunburn protection provided by the sunscreen product.
SPF only indicates a sunscreen’s UVB protection, not UVA protection (see what follows). All
sunscreens are tested to measure the amount of UV radiation exposure it takes to cause a sunburn
when using a sunscreen compared to how much UV exposure it takes to cause a sunburn when not
using a sunscreen. The average person’s skin begins to burn after ten to twenty minutes of sun
exposure. An SPF 30 product would then provide protection from burning about thirty times
longer, so about 300 to 600 minutes. However, the FDA recommends sunscreen to be reapplied at least every two hours, more often if you’re swimming or sweating, as sunscreen is quick to sweat off or wash off in the water.
How do you know how much UVA protection you are getting? In recent years, the United States and a handful of other countries adopted the PA+ rating system initially developed in Japan. The rating goes from one to four plus signs. The highest level of UVA protection recognized in the United States is PA++++. Brands that I use in my clinic, such as Colorescience and SkinMedica, do this additional testing to provide the UVA protection level for their users, even though the FDA has not yet made PA+ testing required as part of their sunscreen testing
4: Water Resistant
There is no such thing as a “waterproof” sunscreen. Current sunscreens that are labeled as “water resistant” are required to be tested according to the SPF tests and are required to state whether the sunscreen remains effective for 40 minutes or 80 minutes when swimming or sweating.
5: The Skin Cancer Foundation Seal of Recommendation
The Skin Cancer Foundation is the only global organization solely devoted to the prevention, early detection, and treatment of skin cancer. It is a trusted resource for the nation’s skin cancer prevention community. Look for the Skin Cancer Foundation Seal of Recommendation to ensure the product you choose is safe and effective.
6: Active Ingredients
As mentioned before, the active ingredients for all products are important, but I think you need to really pay attention to the active ingredients in sunscreen. The ingredients label is most likely found on the back of the bottle, and it lists the main ingredients in the product that protect your skin against UV rays. There are two main types of active sunscreen ingredients: chemical and physical.
Chemical sunscreen works like a sponge, absorbing the sun’s rays. Look for one or more of the active ingredients such as oxybenzone, avobenzone, octisalate, octocrylene, homosalate, and octinoxate. Oxybenzone, octocrylene, and octinoxate have been banned in Key West, Hawaii, and the U.S. Virgin Islands due to the harmful effect that these ingredients have on the coral reefs. If these ingredients are harmful to the coral reefs, what are they doing to your body?
Physical sunscreen (also known as mineral sunscreen) works like a shield; it sits on the
surface of your skin, deflecting the sun’s rays. Look for the active ingredient’s titanium dioxide
and/or zinc oxide. Some sunscreens available in the local big box stores combine both chemical and physical ingredients. The FDA states that physical (mineral) sunscreens are safe but products that use chemicals need more research. Since chemical sunscreens may be harmful to you and to the
environment, I recommend products with only physical ingredients.
Dr. Jacobs talks a lot about sun protection in her book, Live Life Beautifully (With a Little Help). If you’re interested in learning more, you can purchase here.