Vitamin D Plasma Level Variations in Adults With vs Without Sunscreen

Close up on woman applying sun cream on her arm with a spray at the beach on a warm, sunny day. Sunscreen protection, skin cancer concept
Variation in plasma levels of vitamin D with the use of sunscreen in adults exposed to the sun was similar to that of adults exposed without sunscreen.

The following article is part of coverage from the American Academy of Dermatology’s Annual Meeting (AAD 2020). Because of concerns regarding the coronavirus disease 2019 (COVID-19) pandemic, all AAD 2020 sessions and presentations were transitioned to a virtual format. While live events will not proceed as planned, readers can click here to view more news related to research presented during the AAD VMX 2020 virtual experience.

Variation in plasma levels of vitamin D with the use of sunscreen (SPF 30) in adults exposed to the sun was similar to that of adults exposed without sunscreen, according to study results presented at the American Academy of Dermatology’s Virtual Meeting Experience (AAD VMX) 2020, held online from June 12 to 14, 2020.

Researchers sought to evaluate the synthesis of vitamin D with suberythemal sun exposure in healthy adults using SPF 30. Therefore, they conducted an experimental study in Rio de Janeiro, Brazil, in 56 adults who had 25-OH-vitamin D, 25-OH-vitamin D-2, and 25-H-vitamin D-3 checked twice, 24 hours apart, and were exposed to UVB 20 mJ/cm2. Of the 56 adults, 20 were randomly assigned to use sunscreen, 18 to no sunscreen, and 18 to no sun exposures for 24 hours. The participants also avoided food sources of vitamin D and sun exposure from the day before the first vitamin D dosage. The groups were paired according to age, sex, phototype, and body mass index.

The variation in vitamin D serum levels between the no sun exposure group and the group with sunscreen use was statistically significant (mean difference, -1.4677; 95% CI, -2.3437 to -0.5918; P <.001) as well as between the group with no sun exposure and no use of sunscreen (mean difference, -2.2159; 95% CI, -4.1957 a -0.2361; P =.024). However, there were no significant differences between the group with sunscreen and no sunscreen (mean difference, -0.7482; 95% CI, -2.5608 a 1.0645; P =.419).

The study authors noted that real-life clinical trials are necessary to confirm recommendations for clinical practice since the synthesis and metabolism of vitamin D depends on multiple factors. “The generalization of the results for other populations with different diets, clothing coverage of the body, and different solar UVB irradiations should be pondered with caution,” they added.

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Pereira L, da Cruz Filho RA, Luz FB, et al. Vitamin D plasma levels after mild exposure to the sun with photoprotection – is there any variation? Presented at: AAD VMX 2020; June 12-14, 2020. Poster 17954.