It’s a commonly held notion, that sunscreen is the best course of action and the go-to product for keeping ourselves protected from the sun’s harmful UV rays. However, new questions are being proposed about the level of protection sunscreen can provide from the strong summer sun and if you are even using these products correctly in the first place.
In past years, researchers have come forward to warn that although sunscreen is essential for protection, many people are failing to apply it correctly and are therefore not fully reaping its benefits.
This is an unsettling observation, as it’s possible that our skin is failing to be protected from harmful rays and we are not even aware of it.
A brand-new study from King's College London in the United Kingdom—now published in the journal Acta Dermato-Venereologica—is once again offering a similar warning as past research has done, by stating that the average person will generally apply too little sunscreen for it to be effective in the sun.
"There is no dispute that sunscreen provides important protection against the cancer-causing impact of the sun's ultraviolet [UV] rays," says study author Prof. Antony Young.
"However, what this research shows is that the way sunscreen is applied plays an important role in determining how effective it is."
The researchers behind this study carried out their experiment by testing the skin damage on a number of participants. These participants were asked to apply sunscreen as people generally tend to do. Researchers were able to study the DNA of the participant's skin to look for relevant damage.
Generally, the manufacturers of sunscreen products advise applying the cream with a depth of 2 milligrams per square centimeter (mg/cm2) of skin. This is the quantity that manufacturers use as a "landmark" when they calculate the sunscreen’s sun protection factor (SPF) rating.
This guideline may be useful, but it doesn’t deter from the fact that when applying sunscreen, it’s quite difficult to measure the exact thickness of the product we are applying.
The participants of the study were chosen based on their skin type; those with fair skin were chosen as they were likely to be more vulnerable to UV damage.
Overall, the researchers found that sunscreen with a high SPF (SPF 50), if applied in a thin layer, the way people tend to, would provide no more than 40 percent of the anticipated protection.
For this reason, Dr. Young along with the other researchers involved in the experiment are advising people to use a higher SPF sunscreen than they normally would.
"Given that most people don't use sunscreens as tested by manufacturers, it's better for people to use a much higher SPF than they think is necessary” advises Dr. Young.
"This research demonstrates why it's so important to choose an SPF of 30 or more," adds Nina Goad, from the British Association of Dermatologists.
"In theory," she notes, "an SPF of 15 should be sufficient, but we know that in real-world situations, we need the additional protection offered by a higher SPF."