Moisturisers with a sun protection factor (SPF) may not protect your skin as well as you think, because of the way we use them, experts have warned.
As a result, doctors are warning people not to rely on moisturisers with SPF for their main sun protection needs, particularly if spending extended periods in the sun.
According to a study presented at the British Association of Dermatologists’ Annual Conference, moisturisers with SPF provide less sun protection than the equivalent strength sunscreen in “real-world” scenarios as people are more likely to miss areas of their face when using them.
Researchers from the University of Liverpool assessed how effectively people apply sunscreen and sun protection factor (SPF) containing moisturiser to their face, by using a specially modified camera to only see UV light.
When an area of skin is successfully covered, the product absorbs the UV light and this area appears black in the photos – the lighter the area, the less successful the absorption.
Over two separate visits, study participants were asked to apply sun protection – sunscreen in the first visit, and moisturiser with SPF in the second. Pictures were taken with the modified camera to see how effectively people applied the two products.
Analysis of the photos showed that when applying moisturiser, people missed 16 per cent of their face on average, whereas when applying sunscreen, this decreased to 11 per cent.
When just the high-risk eyelid areas were analysed, sunscreen users missed 14 per cent, compared to 21 per cent when using moisturiser.
The study suggests that people do not apply moisturiser as thickly as sunscreen, and therefore do not receive the full benefits of the SPF. On average, the photos of people using moisturiser are noticeably less dark, indicating that the product is absorbing less UV light, according to the study.
Participants were asked to rate their perceived ability to apply the products before and after viewing the images, with the results indicating that participants were not aware of their failure to achieve adequate coverage.
Consultant Ophthalmic and Oculoplastic Surgeon, and one of the researchers, Austin McCormick said: “This research is very visual and fairly easy for people to understand: the darker the image, the more sun protection people are getting.
“We expected the area of face covered with moisturiser to be greater than sunscreen, in particular the eyelids because of the perception that moisturiser stings the eyes less than sunscreen. In fact we found the opposite: the area of the face covered effectively was greater with sunscreen than moisturiser. In addition, where it was applied, the moisturiser provided less UV protection than sunscreen.
“Although skin moisturiser with SPF does provide sun protection, our research suggests that it’s not to the same degree as sunscreen. We do recommend moisturisers and makeup that contain UV protection – it is better than no protection at all, but for prolonged periods in the sun we recommend the application of sunscreen with high SPF.”
Matthew Gass, of the British Association of Dermatologists, said: “Unfortunately, moisturiser with SPF just doesn’t perform particularly well in real world situations compared to sunscreen. Although it may say factor 30 on the box, this study is just further evidence that lab testing conditions for these products don’t reflect how they are used.
“Another important thing to take away from this research is that people often miss areas of their face when applying sun protection, a good way to prevent this from becoming an issue is to wear sunglasses and reapply sunscreen regularly. This should help protect the bits you miss from being exposed to excessive sun.”
— The British Association of Dermatologists (@HealthySkin4All) July 3, 2018
How to stay safe in the sun
In recent years, the popularity of SPF containing moisturisers has steadily increased, and more users are turning to them for their sun-protection needs, the report said.
The study noted that when products are tested for their SPF, they are tested at a density of 2 mg per cm². SPF used in moisturisers is tested the same way as sunscreens, so an SPF 15 moisturiser should provide an SPF of 15. However, according to the study, they are likely to be applied a lot more thinly than sunscreen, and less uniformly.
Applying less SPF will reduce the protection to a higher degree than is proportionate – for example, only applying half the required amount can actually reduce the protection by as much as two-thirds.
It was also noted that moisturisers containing an SPF may not contain any UVA protection and as a result will not protect against UV ageing, and are less likely to be rub-resistant and water resistant.
The study suggests the following sun protection measures:
- Spend time in the shade during the sunniest part of the day when the sun is at its strongest
- Avoid direct sun exposure for babies and very young children
- When it is not possible to limit your time in the sun, keeping yourself well covered, with a hat, T-shirt, and sunglasses, can give you additional protection
- Apply sunscreen liberally to exposed areas of skin. Re-apply every two hours and straight after swimming, sweating or towelling to maintain protection
It’s also important to get into the habit of regularly checking moles for cancer. As the lucky Australians that we are, we enjoy sunny days almost all year round, but exposure to ultraviolet radiation (UV) is inevitable. Visit your local skin cancer specialist and ask for guidance on how to monitor your moles.