What SPF Actually Means & How To Properly Apply Sunscreen

by Lydia Bell

There’s a lot of talk about sunscreen, as it's still the best way to protect your skin from the potentially harmful ultraviolet (UV) rays emitted by the sun. Sunlight is the number one source of UV radiation, according to the American Cancer Institute. Overexposure to the sun can lead to common forms of skin cancer, such as basal cell and squamous cell carcinoma. Wearing hats and sunglasses, staying in the shade, and avoiding the sun during peak hours (10 am - 3 pm) will greatly reduce the risk of sun damage. In addition to these measures, wearing the correct daily SPF is key to achieve sun safety and maintain healthy skin.

What Exactly Does SPF Mean?

SPF, or Sun Protection Factor, is a measure of how long a sunscreen will protect skin from UVA and UVB rays, which cause sunburn, damage skin, and can lead to skin cancer. The higher the SPF number, the greater the amount of protection you’ll get from that sunscreen. For example, if your skin would normally burn after 10 minutes in the sun, applying an SPF 15 sunscreen would allow you to stay in the sun without burning for approximately 150 minutes (a factor of 15 times longer). This is a rough estimate that depends on skin type, intensity of sunlight and amount of sunscreen used. SPF is actually a measure of protection from the amount of UVB exposure and is not meant to help you determine how long you can be exposed to the sun for.

How Much You Should Apply?

For best protection, experts recommend applying the proper amount, about one ounce for full body coverage (the amount of a shot glass), 0.4 ounces to the face (enough to fill the bottom of a shot glass) and reapplying every 2 hours. Most people under-apply sunscreens, using only ¼ to ½ the amount required. This reduces the protective effects of the SPF greatly. For example, a half application of an SPF 30 sunscreen only provides an effective SPF of 5.5!

Our Top Best-Selling Sunscreens

We love the kind of sunscreens that deliver multiple benefits to the skin, such as moisturizing and calming the skin, reducing photo aging and sun damage, on top of their main function to prevent sunburns and block penetration of UV rays. High priorities for sun protective products on our list is that they are long-lasting, don’t clog pores, and are easy to apply. Below, a few of our favorite top selling sunscreens with long-lasting protection and strong skincare benefits!