A trusted summer product many rely on for shelter from burns and long-term skin damage might not work as hard as it claims.
When it comes to the care consumers expect, many sunscreens fail to protect as promised.
After testing and rating more than 60 sunscreens with a labeled sun protection factor (SPF) of 30 or higher, Consumer Reports found that 28 of them, or 43 percent, failed to actually protect at that level. Three sunscreens fell below even SPF 15, which provides far too little sun protection against sunburn, wrinkles and skin cancer.
“When we separated the sunscreens into categories based on the claimed SPF, we found that a significant percentage tested below the number on the label,” researchers at Consumer Reports said. “That was true at every SPF level.”
Alarmingly, for the last four years, these results have held steady. Half of the sunscreens product reviewers tested have registered below the SPF printed on the label. A third of them fell below SPF 30.
“In four years of our sunscreen tests, almost half of the products failed to meet their SPF claim after water immersion—despite the fact that all featured claims of water resistance. And if you trust your skin to mineral products, you’re taking a greater chance; the mineral-only sunscreens performed far worse than the chemical formulations,” Consumer Reports said.
Consumer Reports found that of 85 chemical sunscreens, or 42 percent, failed to meet their SPF claim. Mineral sunscreens, which contain “only titanium dioxide, zinc oxide, or both as active ingredients,” fared worse, with 74 percent of 19 products failing to meet their SPF claims.
Label lies aside, “SPF is not a consumer-friendly number” anyway, said Florida dermatologist James Spencer. It might be confusing to understand what exactly a sunscreen label and SPF number promise.
“The SPF rating is a measure of the time it would take you to sunburn if you were not wearing sunscreen as opposed to the time it would take with sunscreen on,” Salynn Boyles, who works for WebMD, said.
The Skin Cancer Foundation explains how it works: “If it takes 20 minutes for your unprotected skin to start turning red, using an SPF 15 sunscreen theoretically prevents reddening 15 times longer — about five hours.”
However, no sunscreen should be expected to stay effective without reapplication or against common sunscreen errors: using too little or not applying properly.
According to Spencer, an SPF 15 product blocks about 94 percent of UVB rays. An SPF 30 product blocks 97 percent of UVB rays and an SPF 45 product blocks about 98 percent of rays. Sunscreens vary in their ability to protect against UVB rays, which cause sunburn, and UVA rays, which affect the skin more deeply.
Consumer Reports advises choosing “a chemical sunscreen with an SPF of 40 or higher will give you a better chance of getting at least an SPF 30, the minimum level many dermatologists recommend.”
Additionally, they recommend applying sunscreen indoors 15 to 30 minutes before going outside, which allows for better absorption. Sunscreen should be applied liberally, which means rubbing in spray sunscreens. No matter what SPF is used, sunscreen should be reapplied at least every two hours and used even during cloudy and unseasonably cool days.
The study found that while the Food and Drug Administration (FDA) requires manufacturers test their sunscreens, it fails to hold these results to standards or to conduct independent testing. With the results of the four-year study, Consumer Reports will submit its findings to the FDA and ask it to investigate further.