Study Compares Efficacy of Sunscreens and Moisturizers with SPF

Understanding UV Radiation Risks

A recent study conducted by researchers at the University of Liverpool has investigated the effectiveness of traditional sunscreens compared to moisturizers that contain sun protection factor (SPF). The detrimental effects of ultraviolet (UV) radiation, including premature aging and skin cancer, are widely recognized. Despite extensive promotion of SPF products, the rates of both melanoma and non-melanoma skin cancers continue to rise.

Development of SPF Moisturizers

Moisturizers with SPF were created with the intention of encouraging more frequent use than traditional sunscreens, which are typically applied only during periods of expected high sun exposure. Initially, these moisturizers had lower SPF ratings, but many leading brands now offer options with SPF levels comparable to traditional sunscreens, ranging from SPF 30 to 50.

Concerns About Application Techniques

There are ongoing concerns regarding the proper application of moisturizers with SPF. Research indicates that consumers might not apply these products adequately, potentially leading to underestimated UV exposure. This is particularly concerning for the eye region, which has one of the highest incidences of skin cancer.

Focus on the Eye Region

Previous studies have shown that people often neglect to apply sunscreen to their eyelids, an area known to have a high rate of skin cancer. However, limited research exists that specifically evaluates the effectiveness of moisturizers with SPF compared to traditional sunscreens. The University of Liverpool study aimed to determine whether users adequately covered the sensitive areas around their eyes when applying both types of products.

Research Findings on Sunscreen and Moisturizer Application

Study Methodology

The study involved 84 participants, including 22 men and 62 women aged 18 to 57. Both the sunscreen and the moisturizer tested were marketed as SPF 30 and contained titanium dioxide as their primary active ingredient. Although both products were labeled suitable for facial application, they advised avoiding contact with the eyes.

During the first session, participants filled out a pre-study questionnaire, were exposed to UV radiation, and photographed with a UV-sensitive camera before and after applying either the sunscreen or the moisturizer. This process was repeated in a second visit with the alternative product, followed by a post-study questionnaire.

Key Findings

The researchers discovered that participants applied sunscreen more thoroughly than the moisturizer with SPF. Specifically, 11.1% of the total facial area was left uncovered when using sunscreen, while 16.6% was missed when applying the moisturizer. The eyelid and surrounding areas were frequently neglected.

Participants were often unaware of their incomplete coverage and the differences in their application techniques between the two products. Additionally, the findings suggested that participants used a smaller quantity of the moisturizer with SPF compared to the sunscreen, resulting in lower UV protection despite similar efficacy ratings for both products.

Factors Influencing Application

The researchers proposed that the viscosity of the moisturizer with SPF may have contributed to its lower application rate, making it more challenging to spread than the sunscreen. They also considered other factors, such as the size of product containers, which could influence user behavior.

Implications for Skin Cancer Awareness

The study concluded that areas of the face most susceptible to skin cancer are often overlooked when using SPF moisturizers, and that users frequently remain unaware of these deficiencies. Although brief exposure to UV radiation has health benefits, prolonged exposure while using SPF products may lead to cumulative UV damage in unprotected areas.

The researchers advocate for enhanced public education focused on protecting vulnerable areas, such as the eyelids, to mitigate the risk of UV-related skin damage.

References

Lourenco, E. A. J., Shaw, L., Pratt, H., Duffy, G. L., Czanner, G., Zheng, Y., et al. (2019). Application of SPF moisturisers is inferior to sunscreens in coverage of facial and eyelid regions. PLoS ONE, 14(4), e0212548. http://doi.org/10.1371/journal.pone.0212548

IOS Press. (2019, February 21). Sunscreen application has better face coverage than SPF moisturizers. EurekAlert! Retrieved April 9, 2019 from https://www.eurekalert.org/pub_releases/2019-04/p-sah032719.php