If you would like to submit a blog post for consideration, please email firstname.lastname@example.org
[6 min read] How time spent applying sunscreen affects your patients’ skin
Sunscreen is a vital part of everyday skin care for Australians. The nation has the world’s highest rate of skin cancer, with around 800,000 diagnoses every year, and the vast majority of these skin cancers are caused by unprotected exposure to the sun’s UV radiation. UV is also responsible for premature ageing of the skin, resulting in wrinkles, lines, unwanted pigmentation, sun spots, and loss of skin elasticity.
Australians are increasingly turning to aesthetic procedures such as injectable treatments and other rejuvenating therapies to repair the damage caused by our harsh sun. In fact, Australians now spend around $1 billion every year on cosmetic procedures – 40 per cent more per capita than America.
The adage goes that ‘prevention is better than a cure’, and sunscreen is known to be the best prevention available for the damaging effects of the sun’s UVA and UVB rays. Yet many Australians neglect to include it in their day-to-day skin care routine – overseeing its importance among the many serums, lotions and corrective aesthetic treatments on offer.
In order to be effective, sunscreen must be applied in a sufficient quantity and reapplication is recommended. So, while many Australians remember to apply sunscreen as part of their morning routine, some don’t apply enough product and most forget to reapply during the day.
Study: Photoprotection by sunscreen depends on time spent on application
Researchers in Denmark looked at whether time spent on sunscreen application is related to the amount of sunscreen used during a first and second application.
In the study, thirty-one volunteers wearing swimwear applied sunscreen twice in a laboratory environment. Time spent and the amount of sunscreen used during each application was measured. The body surface area accessible for sunscreen application was estimated from their height, weight and swimwear worn. The average applied quantity of sunscreen after each application was calculated.
It was found that people spent on average 4 minutes and 15 seconds on the first application and approximately 85 per cent of that time on the second application. There was a linear relationship between time spent on application and amount of sunscreen used during both the first and the second application.
Participants applied 2.21 grams of sunscreen per minute during both applications. After the first application, subjects had applied a mean quantity of sunscreen of 0.71 mg/cm2 on the body surface area, and after the second application, a mean total quantity of 1.27 mg/cm2 had been applied.
To summarise, it was found that photoprotection by sunscreen depends on time spent on application. This suggests that Australians might be better protected from cutaneous sun damage if they are encouraged to spend more time each day applying a high-SPF product to exposed skin.