• What does SPF mean?
• What does SPF 30 mean?
• What is broad-spectrum sunscreen?
• What are the best sunscreens to use?
• What are other forms of sun protection?

What does the SPF number mean?

According to Dr. Schlessinger, “SPF is an outdated and incomplete way to think of sun protection, but for now, it is all that we have. Truly, there ought to be better ways to classify sun protection, but we are working with an antiquated system and until the FDA allows for a better one, we are just stuck with this.”

SPF is an acronym that stands for sun protection factor. SPF is measured numerically and indicates how long your skin would take to burn with sunscreen versus without. For example, let’s say your skin typically burns after ten minutes in the sun. That means an SPF 15 sunscreen would protect you for fifteen times that or 150 minutes. The higher the SPF, the more protection a sunscreen provides against sunburn. “Regardless of SPF value, I recommend reapplying your sunscreen at least every ninety minutes to two hours, or sooner if you’ve been sweating or in the water,” Dr. Schlessinger says. “After being applied, the ingredients in sunscreen start to break down and reapplication will give you continued protection throughout the day.”

What does SPF 30 mean?

The American Academy of Dermatology recommends using a sunscreen of at least SPF 30. No sunscreen, no matter how high the SPF, blocks 100 percent of the sun’s rays, and as SPF rises, the amount of protection levels off. For instance, a sunscreen with SPF 15 blocks about 93 percent of the sun’s UVB rays, which are responsible for causing sunburn. An SPF 30 sunscreen blocks about 97 percent of UVB rays, and SPF 50 blocks about 98 percent of rays. When selecting a sunscreen, however, you need to look beyond just the SPF number—read on below to find out why.

What is broad-spectrum sunscreen?

Though the SPF value on a sunscreen is important, it isn’t the only thing you should be looking for when choosing a sunscreen. The sun emits two types of UV rays: UVA and UVB. While UVA light is associated with aging and UVB causes burning, both types of rays can cause skin damage that can lead to skin cancer.

The SPF rating on a sunscreen actually only reflects the amount of UVB protection it provides—there is currently no number or rating associated with UVA protection. Dr. Schlessinger recommends sunscreens that have a designation of “broad-spectrum” UVA protection. “Sadly, there just isn’t an easy way to know what UVA protection is offered just from looking at the sunscreen label, and that is why we are very picky about what we sell and recommend on LovelySkin.com,” Dr. Schlessinger says.

Broad-spectrum protection is essential because it indicates the sunscreen protects against UVA rays as well as UVB rays. A sunscreen may provide an SPF upwards of 50, but if it only offers UVB protection, your skin is still susceptible to UVA rays capable of causing sun damage and aging the complexion. “You can have a million SPF and terrible UVA protection and still end up getting huge amounts of sun damage,” Dr. Schlessinger says. “While you probably won’t burn as much if you constantly reapply—as SPF protects against UVB which causes burning—UVA rays cause signs of aging and skin cancer as well. You really need a sunscreen with both, or you will have issues in the future.”

What are the best sunscreens to use?

When choosing a sunscreen, you’ll want to look for an SPF of 30 or higher as well as the keywords “broad-spectrum” on the label, which indicate that the sunscreen will protect your skin against both UVA rays, which age the skin, and UVB rays, which burn the skin. The active ingredients in broad-spectrum sunscreens include mineral-derived blockers such as titanium dioxide and zinc oxide as well as chemical blockers such as oxybenzone, octocrylene, avobenzone, homosalate and octinoxate. (You can learn more about the difference between mineral and chemical sunscreens here).

Wearing sunscreen and reapplying it often is just one part of practicing sun safety. Here are some other tips from Dr. Joel Schlessinger to help you stay safe in the sun:

• Seek the shade during the sun’s peak hours, 10 a.m. to 2 p.m.
• Protect your eyes by wearing sunglasses.
• Cover your skin with UPF-protective clothing when possible, including long-sleeve rashguards for swimming.
• A wide-brimmed hat provides an extra layer of protection, shading areas of skin that easily burn such as your ears, nose and neck.

Have you heard of sunscreen pills? You can learn more about dietary supplements such as Heliocare that can help protect your skin from photoaging and skin cancer on the LovelySkin Blog.