Everybody’s free (to wear sunscreen)
Sunscreen does not compromise vitamin D levels, study shows
Writing in the British Journal of Dermatology, the team behind the study noted that suggestions sunscreen use can lead to vitamin D deficiency have been circulating for some time – however no research has looked into the potential issue.
There are, of course, both short- and long-term risks associated with exposure to the sun’s harmful ultraviolet (UV) rays, which has led to a concerted campaign for us all to cover up and use sunscreen.
While this advice suggesting we need to protect ourselves from the damaging UV rays of the sun has been well received, and reduced levels of potentially deadly skin cancers, it has also created a more recent concern that consistent use of sunscreen may mean vitamin D levels become a worry.
"Sunlight is the main source of vitamin D. Sunscreens can prevent sunburn and skin cancer, but there has been a lot of uncertainty about the effects of sunscreens on vitamin D," commented lead author Professor Antony Young, of King's College London.
"Our study, during a week of perfect weather in Tenerife, showed that sunscreens, even when used optimally to prevent sunburn, allowed excellent vitamin D synthesis."
Everybody’s free (to wear sunscreen)
Young and colleagues studied the impact of sunscreens on vitamin D status during a one‐week sun‐holiday in Tenerife (28°N).
Comparisons were made between two formulations, each with a sun protection factor of 15. The UVA protection factor (UVA‐PF) was low in one case and high in the other.
Healthy Polish volunteers (n=20 per group) were given the sunscreens and advised on correct application.
Comparisons were also made with discretionary sunscreen use (n=22) and non‐holiday groups (51o5N, n=17).
Sunscreen use, behaviour, UVR exposure, clothing cover and sunburn were monitored, while serum levels of vitamin D were measured as 25(OH)D.
The team reported that the use of intervention sunscreens was the same, and that both equally stopped sunburn that was present in the discretionary use group. They also recorded an increase of vitamin D in participants during a week of cloudless weather, with very high UV index, even when sunscreens were used properly and prevented sunburn.
“A high UVA‐PF sunscreen enables significantly higher vitamin D synthesis than a low UVA‐PF sunscreen because the former, by default, transmits more UVB than the latter,” added the team – noting that the synthesis of vitamin D relies on UV-B.
As a result, the team concluded that the benefits of sunscreen use can be obtained without compromising vitamin D levels.
Source: British Journal of Dermatology
Published online ahead of print, doi: 10.1111/bjd.17888
“Optimal sunscreen use, during a sun‐holiday with a very high UV index, allows vitamin D synthesis without sunburn”
Authors: A.R. Young, et al
