Sunscreen use and its effect on vitamin D levels
Alongside this shift, a persistent question has emerged: does sunscreen block Vitamin D production? The concern is understandable. Vitamin D is produced in the skin through exposure to ultraviolet B (UVB) radiation, the same portion of sunlight that sunscreens are designed to reduce.
Yet the relationship between sunscreen use and Vitamin D status is often simplified, leading to confusion. According to decades of photobiology research summarised in Feldman and Pike’s Vitamin D (5th ed.) [1], the answer is more nuanced than commonly assumed.
WHAT SUNSCREEN DOES IN THEORY
You can read here about how Vitamin D is synthesized by the skin when it is exposed to UVB radiation. In laboratory tests, sunscreens with a high sun protection factor (SPF) often significantly reduce the transmission of UVB radiation to the skin [2]. In theory, this could suggest that SPF use in general limits the cutaneous production of Vitamin D₃. However, these tests often assume that: the application of SPF by the user is thick and uniform; the application is complete and covers all areas of the skin; the product does not degrade or get displaced through sweating and movement. In other words, the conditions of the lab rarely reflect the way that we use SPF products in everyday life.
WHAT SUNSCREEN ACTUALLY DOES
In practice, sunscreen is typically applied less generously, more unevenly, and reapplied less consistently than it is in a lab. As a result, some UVB penetration usually still occurs even when we use sunscreen.
We therefore find that routine sunscreen use does not consistently or necessarily result in lower Vitamin D levels [3][4][5]. Individuals who regularly use sunscreen are often exposed to sunlight for longer periods overall, offsetting reductions in UVB transmission [4][5].
This distinction between theoretical blockage and practical exposure is central to understanding why sunscreen use and Vitamin D deficiency are not reliably linked.
BEHAVIOUR MATTERS MORE THAN FORMULATION
The most significant determinant of Vitamin D status is not sunscreen itself, but overall sun exposure [4][5]. Feldman and Pike's highlights that time spent outdoors, clothing coverage, latitude, season, and lifestyle patterns exert a greater influence on Vitamin D synthesis than sunscreen use alone [1].
For this reason, sunscreen use and Vitamin D synthesis are not considered to be competing priorities. Preventing excessive UVB exposure remains essential for skin health. At the same time, Vitamin D requirements can be met through a combination of incidental sunlight exposure, dietary intake, and supplementation.
WHERE SUPPLEMENTATION FITS IN
Vitamin D status is maintained over time. Though sunscreen does not pose a real limit to Vitamin D intake, it does belong to a range of factors that can affect levels over time, along with indoor lifestyles, seasonal changes, protective clothing, living at higher latitudes and diet. To offset these factors, Vitamin D intake and supplementation play an important role. Supplementation provides a UV independent source of Vitamin D, allowing individuals to maintain adequate status without compromising skin protection strategies [1]. This is especially relevant in winter months, when UVB radiation may be insufficient for cutaneous Vitamin D synthesis regardless of sunscreen use.
WHY THIS MATTERS
Public concern about sunscreen and Vitamin D reflects a broader challenge. It involves reconciling evolutionary biology with modern health practices. Sunscreen changes how sunlight interacts with the skin, but it does not negate the body’s ability to maintain Vitamin D status when other sources are considered.
Understanding this distinction helps reduce unnecessary anxiety and supports informed, balanced health decisions.
CONCLUSION
Sunscreen reduces UVB exposure by design, but its impact on Vitamin D production in everyday life is often overstated. According to the scientific evidence, routine sunscreen use does not reliably cause Vitamin D deficiency [3][4][5], though recent evidence suggests high-SPF daily use may modestly reduce levels over time [6].
Maintaining Vitamin D status in a modern environment is best achieved through a combination of sensible sunlight exposure, diet, and supplementation, while continuing to protect skin health through appropriate sun protection practices.
DISCLAIMER
This article is for educational and informational purposes only. It does not constitute medical advice. Health claims are made in accordance with EU Regulation (EC) No 1924/2006. Individuals concerned about vitamin D intake or sun exposure should consult a qualified healthcare professional.
REFERENCES
[1] Holick MF, Slominski AT. Photobiology of vitamin D. In: Hewison M, Bouillon R, Giovannucci E, Goltzman D, Meyer M, Welsh J, eds. Feldman and Pike’s Vitamin D. Volume One: Biochemistry, Physiology and Diagnostics. 5th ed. Academic Press; 2024.
[2] Matsuoka LY, Ide L, Wortsman J, MacLaughlin JA, Holick MF. Sunscreens suppress cutaneous vitamin D3 synthesis. J Clin Endocrinol Metab. 1987;64(6):1165-1168. doi:10.1210/jcem-64-6-1165.
[3] Marks R, Foley PA, Jolley D, Knight KR, Harrison J, Thompson SC. The Effect of Regular Sunscreen Use on Vitamin D Levels in an Australian Population: Results of a Randomized Controlled Trial. Arch Dermatol. 1995;131(4):415-421. doi:10.1001/archderm.1995.01690160043006.
[4] Neale RE, Khan SR, Lucas RM, Waterhouse M, Whiteman DC, Olsen CM. The effect of sunscreen on vitamin D: a review. Br J Dermatol. 2019;181(5):907-915. doi:10.1111/bjd.17980.
[5] Passeron T, Bouillon R, Callender V, Cestari T, Diepgen TL, Green AC, van der Pols JC, Bernard BA, Ly F, Bernerd F, Marrot L, Nielsen M, Verschoore M, Jablonski NG, Young AR. Sunscreen photoprotection and vitamin D status. Br J Dermatol. 2019;181(5):916-931. doi:10.1111/bjd.17992.
[6] Tran V, Duarte Romero BL, Andersen H, Clarke M, Collins LG, Dawson T, Hartel G, Lefevre JG, Lucas RM, McLeod DSA, Milne RL, Sinclair C, Whiteman DC, Waterhouse M, Neale RE. Effect of daily sunscreen application on vitamin D: findings from the open-label randomized controlled Sun-D Trial. Br J Dermatol. 2025;193(6):1128-1137. doi:10.1093/bjd/ljaf310. PMID: 40927943.
