Your body can produce vitamin D when the skin is exposed to UVB rays,[1] so it stands to reason that sunscreen use may decrease vitamin D levels. Indeed, sunscreen can cause a drop in vitamin D production under laboratory testing conditions,[2][3] and this decrease is most notable if sunscreen is used consistently and properly (i.e., when using a broad-spectrum sunscreen and the right SPF, amount, and reapplication schedule).[4][5][6] Even so, it appears that most people need not worry about the effects of sunscreen alone on vitamin D levels.[7]
One important caveat — studies to date have generally been conducted on people with less skin pigmentation (i.e., those with Fitzpatrick skin types 1–3). A different result may be seen in those with Fitzpatrick skin types 4–6.
Generally speaking, 5 to 30 minutes of unprotected sun exposure to the hands, face, and arms at least three times a week between 11 a.m. and 3 p.m. may generally be enough to keep vitamin D levels out of the deficient range (<30 nmol/L or <12 ng/mL).[8][9] When the UV Index in your area is 3 or higher, people with Fitzpatrick skin types 1 or 2 should limit unprotected sun exposure to less than 10 minutes, skin types 3 or 4 to less than 15 minutes; and skin types 5 or 6 to less than 30 minutes.[10][11] You can check out the UV index forecast in your area here (https://www.epa.gov/enviro/uv-index-search).
Keep in mind that longer periods of unprotected sun exposure will not necessarily lead to higher vitamin D production because the UVB rays will eventually degrade vitamin D in your skin to an inactive state.[12] This actually helps protect your body against vitamin D toxicity. Additionally, UVB-induced vitamin D production can be influenced by many other factors, including:[13]
👴🏽 Age
🦵🏼 Amount of sun-exposed skin
💊 Certain medications
🎽 Clothing type
🏔 Elevation
🗺 Latitude
🏬 Living environment (e.g., urban, suburban, or rural)
🏭 Pollution
✋🏿 Skin pigmentation
📐 Solar angle
⏱ Sun exposure duration and frequency
📅 Time of year
🌦 Weather conditions
For these reasons, it is not advisable to completely forego sunscreen to increase vitamin D levels or rely on sun exposure as your main source of vitamin D. Rather, a more balanced approach would be to increase vitamin D through diet and supplementation, with some limited unprotected sun exposure added in.
References
- ^Bikle DDVitamin D metabolism and function in the skinMol Cell Endocrinol.(2011 Dec 5)
- ^A Faurschou, D M Beyer, A Schmedes, M K Bogh, P A Philipsen, H C WulfThe relation between sunscreen layer thickness and vitamin D production after ultraviolet B exposure: a randomized clinical trialBr J Dermatol.(2012 Aug)
- ^Mantas Grigalavicius, Vladimir Iani, Asta JuzenieneLayer Thickness of SPF 30 Sunscreen and Formation of Pre-vitamin DAnticancer Res.(2016 Mar)
- ^Libon F, Courtois J, Le Goff C, Lukas P, Fabregat-Cabello N, Seidel L, Cavalier E, Nikkels AFSunscreens block cutaneous vitamin D production with only a minimal effect on circulating 25-hydroxyvitamin DArch Osteoporos.(2017 Dec)
- ^Bibi Petersen, Hans Christian WulfApplication of sunscreen--theory and realityPhotodermatol Photoimmunol Photomed.(Apr-Jun 2014)
- ^R E Neale, S R Khan, R M Lucas, M Waterhouse, D C Whiteman, C M OlsenThe effect of sunscreen on vitamin D: a reviewBr J Dermatol.(2019 Nov)
- ^T Passeron, R Bouillon, V Callender, T Cestari, T L Diepgen, A C Green, J C van der Pols, B A Bernard, F Ly, F Bernerd, L Marrot, M Nielsen, M Verschoore, N G Jablonski, A R YoungSunscreen photoprotection and vitamin D statusBr J Dermatol.(2019 Nov)
- ^Barbara B Shih, Mark D Farrar, Marcus S Cooke, Joanne Osman, Abigail K Langton, Richard Kift, Ann R Webb, Jacqueline L Berry, Rachel E B Watson, Andy Vail, Frank R de Gruijl, Lesley E RhodesFractional Sunburn Threshold UVR Doses Generate Equivalent Vitamin D and DNA Damage in Skin Types I-VI but with Epidermal DNA Damage Gradient Correlated to Skin DarknessJ Invest Dermatol.(2018 Oct)
- ^Institute of Medicine (US) Committee to Review Dietary Reference Intakes for Vitamin D and Calcium, A Catharine Ross, Christine L Taylor, Ann L Yaktine, Heather B Del ValleDietary Reference Intakes for Calcium and Vitamin D
- ^Ann R Webb, Andreas Kazantzidis, Richard C Kift, Mark D Farrar, Jack Wilkinson, Lesley E RhodesColour Counts: Sunlight and Skin Type as Drivers of Vitamin D Deficiency at UK LatitudesNutrients.(2018 Apr 7)
- ^Ann R Webb, Andreas Kazantzidis, Richard C Kift, Mark D Farrar, Jack Wilkinson, Lesley E RhodesMeeting Vitamin D Requirements in White Caucasians at UK Latitudes: Providing a ChoiceNutrients.(2018 Apr 17)
- ^A R Webb, B R DeCosta, M F HolickSunlight regulates the cutaneous production of vitamin D3 by causing its photodegradationJ Clin Endocrinol Metab.(1989 May)
- ^Wacker M, Holick MFSunlight and Vitamin D: A global perspective for healthDermatoendocrinol.(2013 Jan 1)
- ^Engelsen O, Kylling AFast simulation tool for ultraviolet radiation at the earth's surfaceOpt Eng.(2005 Apr)
- ^John C Dowdy, Robert M Sayre, Michael F HolickHolick's rule and vitamin D from sunlightJ Steroid Biochem Mol Biol.(2010 Jul)
- ^Vitaly Terushkin, Anna Bender, Estee L Psaty, Ola Engelsen, Steven Q Wang, Allan C HalpernEstimated equivalency of vitamin D production from natural sun exposure versus oral vitamin D supplementation across seasons at two US latitudesJ Am Acad Dermatol.(2010 Jun)
- ^Ann R Webb, Ola EngelsenCalculated ultraviolet exposure levels for a healthy vitamin D statusPhotochem Photobiol.(Nov-Dec 2006)