Does Sunscreen Cause Vitamin D Deficiency? Reviewing the Evidence
Many individuals who prioritize skin protection or evaluate tanning practices wonder if applying sunscreen prevents the body from synthesizing necessary vitamin D. A systematic review published in 2019 in The British journal of dermatology set out to evaluate this question directly. By examining dozens of published studies across several decades, researchers analyzed how sunscreen application influences circulating vitamin D3 and 25-hydroxyvitamin D, also written as 25(OH)D.
What did the 2019 systematic review investigate?
The paper, titled The effect of sunscreen on vitamin D: a review., investigated whether using sunscreen increases the risk of developing a vitamin D deficiency. Sunscreen application is well established as a way to prevent skin cancer, but ongoing concerns have suggested that blocking ultraviolet radiation might reduce vitamin D production. To evaluate the scientific evidence, the study authors collected and assessed English-language papers published between 1970 and 21 November 2017.
How was this systematic review designed?
The investigators followed the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. Rather than relying on a single test group, the review cataloged and analyzed eligible studies across three distinct categories:
- Experimental studies: Four experimental studies assessed sunscreen use under artificially generated ultraviolet radiation sources.
- Field trials: Three field trials examined participants in real-world environments, including two randomized controlled trials assessing daily sunscreen application.
- Observational studies: Sixty-nine observational studies evaluated real-world participants. For these, two authors extracted data and applied a quality scoring criteria developed specifically for this research topic.
Why did laboratory experiments differ from real-world results?
In the four experimental studies, applying sunscreen considerably abrogated the production of vitamin D3 or 25(OH)D caused by exposure to artificial UVR. However, the authors highlighted a major design limitation of those laboratory tests: they used artificially generated ultraviolet radiation with a spectral output unlike that seen in terrestrial sunlight. Because artificial lamps in a lab do not reproduce natural terrestrial sunlight, experimental findings demonstrate a theoretical risk rather than what actually occurs during typical outdoor sun exposure.
What did field trials and observational studies show?
When looking at human exposure in everyday settings, the results were very different from the artificial laboratory setups. The randomized controlled field trials found no effect of daily sunscreen application on circulating vitamin D levels. Furthermore, the 69 observational studies mostly found no association between sunscreen use and reduced vitamin D, or found that self-reported sunscreen use was actually associated with higher 25(OH)D concentrations. Exploring topics like vitamin D and sun exposure helps explain this finding, as people who regularly wear sunscreen often spend substantial time outdoors in the sun compared to individuals who avoid outdoor exposure altogether.
What are the limitations of this evidence?
Although the systematic review provides reassuring data regarding real-world habits, the authors outlined clear limitations that keep the question open to further study:
- Moderate protection levels: The randomized controlled field trials tested sunscreens that offered only moderate protection, specifically an SPF of approximately 16.
- Absence of high-SPF trials: There were no trials evaluating the very high sun protection factor sunscreens that are currently recommended and widely used. Reviewing standard sunscreen SPF ratings is helpful when evaluating how historical trials relate to modern formulations.
- Study designs: Most available evidence came from observational reports rather than controlled clinical interventions.
Should concerns about vitamin D stop you from using sunscreen?
The review concluded that there is little evidence that sunscreen decreases 25(OH)D concentrations when applied in real-life settings. As a result, the authors emphasized that concerns regarding vitamin D should not negate established skin cancer prevention advice. Protecting your skin from ultraviolet rays remains critical for cellular health. If you have questions about your personal vitamin D levels or sun safety regimen, consult a board-certified dermatologist or primary care doctor for personalized medical evaluation.
Sources
Published October 28, 2026. Sources are linked in the text. See our Medical Disclaimer.