There’s no getting around it: You need to be wearing sunscreen. Every day. Even when it’s overcast. Even in the winter. Even if you’re just sitting inside (and there’s a window in the room). It’s the single best way to prevent signs of aging, sun damage and, more critically, skin cancer.
With so many different options on the market and so much information out there, picking one can be a difficult task. I like to tell my patients: The best sunscreen is the one that you’ll actually apply. But to be more discerning, here’s everything you need to know.
SPF—short for Sun Protection Factor—is the rating given to sunscreen based on how well it screens or reflects the sun’s UVB rays. SPF 15 blocks 93 percent of UVB rays, SPF 30 blocks 97 percent and SPF 50 blocks 98 percent.
You should be wearing sunscreen with a minimum SPF of 30. You can, of course, go higher—especially if you tend to burn easily. But remember: No sunscreen can protect against 100 percent of the sun’s rays.
The truth is that you’re probably not using as much sunscreen as you’re supposed to be. In fact, according to the Journal of the American Academy of Dermatology, the average person only applies about a one-quarter to one-half of the recommended amount—which means they aren’t getting the full amount of protection promised on the label.
So, what is the recommended amount? An adult should be using three to four (heaping) tablespoons—or about a shot-glass full—to apply a thick layer of sunscreen all over their body. You should also be using about a teaspoon for your face and neck area alone. (Don’t forget your ears!) You can measure this out by squeezing generous strips of sunscreen on your index and middle fingers.
Always apply sunscreen to the parts of your skin that are exposed, including your hands. For an extra layer of protection during summer months when the sun is more intense, you can even wear UPF clothing—items designed to absorb or block the sun’s rays.
Always read the label of the specific product you’re using for clear directions, but most sunscreens start to lose effectiveness after a few hours. Apply every couple of hours for the best protection—even if you’re wearing makeup—or after swimming or playing sports. There are many different options for reapplication, including mineral-based makeup or compacts, which make reapplication easy on-the-go.
Yes! Broad-spectrum sunscreens are products that protect against both UVA rays—ultraviolet rays that are most associated with aging and skin damage—and UVB rays—the ultraviolet light most responsible for causing sunburns and malignant melanomas. Both types of UV rays are harmful (UVA rays can still play a role in cancer formation), and you need to be protecting yourself from both. Keep in mind that a sunscreen’s SPF rating only measures its effectiveness against UVB rays.
Chemical sunscreens absorb the sun’s rays before they get through your skin and tend to be easier to apply. Physical sunscreens, which are also known as mineral sunscreens, protect your skin by deflecting UV rays. They’re formulated with titanium dioxide and/or zinc oxide, which are gentler on sensitive skin.
Not only is it safe to use, it provides you with necessary protection. Some people are concerned because of past studies that show the ingredients in chemical sunscreens can be found in the bloodstream days after application. But there’s no concrete evidence that this is causing any long-term harm. After all, sunscreen isn’t the only thing we apply topically every day. If you’d like to practice an abundance of caution, opt for a mineral sunscreen.
The Canadian Dermatology Association sums it up best: There’s stronger evidence about the risks associated with sun exposure than there is about the hypothetical negative effects of daily sunscreen use. Prioritize protecting yourself.