Is Higher SPF Sunscreen Better? Study Recommends SPF 100+

It would seem intuitive that a higher SPF sunscreen would mean more protection, right? But official sunscreen wisdom currently says it doesn't make a real difference — the debate is enough that "there is controversy right now in the FDA on whether SPF 100-plus should be allowed on the label of sunscreens," Joshua Zeichner, director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City, tells Allure. According to a new study, using a higher SPF really can make a big difference.

First, a little math. SPF, which stands for "sun protection factor," indicates how much sun exposure you're actually getting when you're outside. "SPF 15 protects against 93 percent of UVB rays, SPF 30 protects against 97 percent, and SPF 50 is about 98 percent," says Sejal Shah, a dermatologist in New York City.

You May Also Like

SkinThe Best Premakeup Moisturizers According to the Pros

SkinI Tried Peace Out Pore Strip Stickers to Remove My Blackheads

In other words, you get double the sun exposure when you opt for SPF 15 instead of SPF 30. To give you a visual, "a product with an SPF 30 means that you get the same amount of sun exposure after 30 minutes outside as you would get if you were unprotected outdoors for one minute," Zeichner adds. Since no product can be 100 percent effective, there's not a whole lot of room for improvement after 97 or 98 percent, but researchers were determined to find out if using SPF 100 made a tangible difference in reducing sun damage.

In a group of 199 adult participants, researchers had each person use a different SPF on each side of their face — SPF 50 on one side and SPF 100 on the other side — before spending a day in natural sunlight. The following day, the researchers measured the sun damage present on each side of participants' faces. Turns out, the SPF 100 really did make a difference. "Didn't matter your skin type, age, or gender, the SPF 100 was always better," Darrell Rigel, clinical professor of dermatology at New York University Langone Medical Center and an author on the study, which was funded by Johnson & Johnson Consumer Inc., tells Allure. Rigel and his co-authors found 55 percent of the participants were more sunburned on the SPF 50 side than they were on the SPF 100 side, according to the findings published in the Journal of the American Academy of Dermatology.

"People were about 10 times more likely to burn on the SPF 50 side than the SPF 100 side," Rigel says. Given the results, the researchers concluded that SPF 100 is "significantly more effective in protecting against sunburn than SPF 50."

So, what does this mean for your sunscreen routine? Up your SPF. "Prior to this study, I commonly recommended broad-spectrum sunscreen with higher SPFs if people are going to be outdoors, especially if for prolonged periods of time, so I will continue to do so," says Shah.

Keep in mind, the effectiveness of your SPF, no matter how high, depends on how well you apply it. "People typically only apply 25 to 50 percent of the rated amount. So if you're using SPF 30 sunscreen, you might only be getting SPF 7 in reality," explains Rigel. For your face, you should be using a quarter-sized dollop, and a shot glass-size for your bod, says Zeichner.

On top of that, reapply every two hours and pay attention to oft missed spots like eyelids, scalp and hairline. "The amount of UV light that penetrates into the skin is significantly more than you would expect based on the label on the bottle if you are not using it correctly," Zeichner says.

You also need to make sure to look for a sunscreen with "broad spectrum" on the label to make sure you're getting protection from UVA rays as well. "UVA rays are responsible for early skin aging and skin cancer, while UVB rays are responsible for sunburn," says Zeichner.

You've heard it a million times before, but we'll say it again: Always wear sunscreen, and the higher the SPF, the better.

---

Read more stories about sun protection:

---

Now, find out the science of sunscreen: