SPF- The Real Meaning

We all know sun protection is important. When looking for sunscreen, the usual philosophy is "the higher the SPF, the better, right?" But what exactly is SPF? What does it mean & what level if SPF should we be buying?

SPF stands for Sun Protection Factor. It refers to the theoretical amount of time you can stay in the sun without getting sunburned. For example, an SPF of 15 would allow you to stay in the sun 15 times longer than you could without protection. In addition, a higher SPF blocks out more rays—a product with an SPF of 15 will filter out approximately 93 percent of UVB rays; SPF 30 filters out about 97 percent.

However, it's not always this straightforward. Different factors can easily effect sunscreens effectiveness. Factors such as water, sweat, applying unevenly & even your genetic makeup. If you have fair skin or if there is a history of skin cancer in your family, you may be at higher risk for skin cancer. Finally, certain medications—such as antibiotics or products with retinol—can make your skin more sensitive to the effects of sunlight. 

It’s also important to know that SPF only applies to UVB rays. There is no SPF equivalent for UVA. You can look for additional ingredients in your sunscreen to protect you from UVA—such as zinc oxide and titanium dioxide—but there’s no standard measurement for how long these ingredients will keep you protected.

For all of these reasons, it is important to not solely rely on SPF to gauge how much time you can spend in the sun. Keep these tips in mind: buy a sunscreen that protects against UVA & UVB rays, reapply sunscreen at least every two hours, cover up with protective clothing and sunglasses, check your skin regularly for any signs of skin cancer and finally, wear a Sunburn Alert UV Wristband or Sticker for an extra reminder of when to reapply sunscreen and get out of the sun. 

What SPF do you wear?