Comparing beach umbrella vs. SPF 100 sunscreen to protect beachgoers from sun

How did sun protection compare for people who spent 3½ hours on a sunny beach with some under an umbrella and others wearing SPF 100 sunscreen? A new article published online by JAMA Dermatology reports neither method used alone completely prevented sunburn, although the SPF 100 sunscreen was more efficacious in the randomized clinical trial.

Hao Ou-Yang, Ph.D., of Johnson & Johnson Consumer, Inc., Skillman, N.J., and coauthors used actual conditions to monitor the sun protection of a standard beach umbrella compared with the high SPF sunscreen. Johnson & Johnson Consumer Inc. is the parent company of Neutrogena Corp. and manufacturer of the sunscreen tested in this study.

Seeking shade is a widely used practice to avoid direct sun exposure. People often assume their skin is fully protected as long as they are under the shade of an umbrella. Few clinical studies have examined the UV protectiveness of a beach umbrella or compared it directly with sunscreen.

The study - conducted over a few days in August 2014 in Lake Lewisville, Texas - included 81 participants, with 41 who used an umbrella and 40 who used SPF 100 sunscreen for protection on a sunny beach at midday. The beachgoers were examined for sunburn on their bodies (face, back of neck, upper chest, arms and legs) about a day after sun exposure.

Authors report 78 percent of participants who were under the shade of a beach umbrella developed sunburn compared with 25 percent of participants who used SPF 100 sunscreen. There were 142 sunburn incidences in the umbrella group and 17 in the sunscreen group, according to this side-by-side study.

Limitations of the study include that only one type of beach umbrella was evaluated.

"Umbrella shade alone may not provide sufficient sun protection during extended exposure to UV rays. Although the SPF 100 sunscreen was more efficacious than the umbrella, neither method alone prevented sunburn completely under actual use conditions, highlighting the importance of using combinations of sun protection practices to optimize protection against UV rays," the article concludes.