Visible Light Protection: Needs and Strategies for Diverse Patients

Image Credit: © Cavan Images - stock.adobe.com

Introduction

Research advances within the photoprotection field demonstrate that visible light radiation (400-700 nm), which accounts for 45% of sunlight, can act synergistically with UV-A radiation to induce oxidative stress and cause both immediate and persistent skin darkening, particularly in individuals with Fitzpatrick skin phototype III and higher.^1-4 We now understand that it is the blue-violet component of visible light, known as high-energy visible (HEV) light (415-455 nm), that is the main contributor to long-lasting hyperpigmentation in individuals with skin of color, as epidermal melanocytes can detect blue light through opsin 3 photoreceptors, which trigger melanin synthesis via tyrosinase activation.^5-7

Findings from several studies indicate that incorporating metal oxides, such as iron oxides, titanium dioxide (TiO2), and zinc oxide (ZnO), and other pigments into formulations offers visible light protection.^8-12 Findings from a study by L’Oréal USA Research and Innovation, in collaboration with Pearl Grimes, MD, FAAD, demonstrated that iron oxide formulations provided superior protection against visible light-induced hyperpigmentation in patients with skin of color compared with a nontinted mineral sun protection factor (SPF) 50+ sunscreen.¹¹ These initial findings suggested that iron oxide formulations offer a dual benefit: masking existing pigmentation while preventing further dyschromia caused by visible light exposure.

The growing popularity of tinted sunscreens, driven by public concerns about visible/blue light’s skin effects, is challenged by a lack of regulatory standards proving protection efficacy (unlike existing SPF and broad-spectrum labeling for UV protection), and limited shade ranges that often exclude darker skin tones despite universal claims.^13-15

To help bridge these gaps, several guidelines have emerged to help clinicians advise patients on selection and usage, considering ingredients and cosmetic suitability.^16-18 Additionally, researchers have made research progress in developing methods to measure visible/blue light protection efficacy of products, including a colorimetry-based visible light protection factor and an in vitro transmittance method predicting in vivo photoprotection.^13,19 Given the increasing dermatological recommendation of iron oxides in sunscreens for visible light–induced skin conditions and the absence of regulatory guidelines for proving efficacy, there is a need to evaluate the visible/blue light protection of commercialized tinted sunscreens.²⁰

New Research Objective

In view of this, we saw the opportunity and initiated a new photoprotection knowledge study with the objective to assess the HEV light–blocking potential of various tinted sunscreens after blue light irradiation, leveraging the in vitro transmittance spectroscopy method.^19,21

Our test included organic, inorganic, and hybrid tinted sunscreen formulations with SPF levels ranging from 30 to 50, varying UV filter systems, antioxidant types, and iron oxide concentrations to account for different shades.

There were 2 key takeaways from our new in vitro study:

1. Consistent with prior reports, tinted sunscreens with iron oxides showed higher HEV absorbance compared with nontinted sunscreens.

2. Interestingly, our new mineral-tinted sunscreens, formulated with iron oxides and a combination of both inorganic filters (ZnO and TiO2), demonstrated higher HEV absorbance profiles and blocking potential after blue light irradiation compared with comparator darker-tinted organic sunscreens or hybrid ones, where 1 inorganic UV filter was present.

Closing Remarks

Evidence that visible radiation (45% of sunlight) induces long-lasting cutaneous responses has created the need to find nontraditional and inclusive strategies for photoprotection beyond UV. Our new in vitro findings suggest that not all tinted sunscreens containing iron oxides are created equal in terms of protection efficacy against blue light exposure.²¹ This underscores the need for further research, standardized testing methodologies, and patient education to address misconceptions about sun protection.^13,19,22 The growing availability of inclusive tinted sunscreens, particularly for darker skin tones, also offers a chance to promote customized daily sun protection and improve adherence across diverse phototypes, as cosmetic elegance and suitable tones are key to patient adherence.^16-18,23 We hope that our new research and inclusive products help support clinicians on photoprotection strategies to consider for all patients, particularly for patients with skin of color.^11,12,21

Hawasatu Dumbuya, PhD

Hawasatu Dumbuya, PhD, is director of clinical research and medical affairs for La Roche-Posay at L’Oréal USA.

References

1. Mahmoud BH, Ruvolo E, Hexsel CL, et al. Impact of long-wavelength UVA and visible light on melanocompetent skin. J Invest Dermatol. 2010;130(8):2092-2097. doi:10.1038/jid.2010.95

2. Ramasubramaniam R, Roy A, Sharma B, et al. Are there mechanistic differences between ultraviolet and visible radiation induced skin pigmentation? Photochem Photobiol Sci. 2011;10(12):1887-1893. doi:10.1039/c1pp05202k

3. Randhawa M, Seo I, Liebel F, Southall MD, Kollias N, Ruvolo E. Visible light induces melanogenesis in human skin through a photoadaptive response. PLoS One. 2015;10(6):e0130949. doi:10.1371/journal.pone.0130949

4. Kohli I, Zubair R, Lyons AB, et al. Impact of long-wavelength ultraviolet A1 and visible light on light-skinned individuals. Photochem Photobiol. 2019;95(6):1285-1287. doi:10.1111/php.13143

5. Regazzetti C, Sormani L, Debayle D, et al. Melanocytes sense blue light and regulate pigmentation through opsin-3. J Invest Dermatol. 2018;138(1):171-178. doi:10.1016/j.jid.2017.07.833

6. Haltaufderhyde K, Ozdeslik RN, Wicks NL, Najera JA, Oancea E. Opsin expression in human epidermal skin. Photochem Photobiol. 2015;91(1):117-123. doi:10.1111/php.12354

7. Ozdeslik RN, Olinski LE, Trieu MM, Oprian DD, Oancea E. Human nonvisual opsin 3 regulates pigmentation of epidermal melanocytes through functional interaction with melanocortin 1 receptor. Proc Natl Acad Sci U S A. 2019;116(23):11508-11517. doi:10.1073/pnas.1902825116

8. Boukari F, Jourdan E, Fontas E, et al. Prevention of melasma relapses with sunscreen combining protection against UV and short wavelengths of visible light: a prospective randomized comparative trial. J Am Acad Dermatol. 2015;72(1):189-190.e1. doi:10.1016/j.jaad.2014.08.023

9. Duteil L, Esdaile J, Maubert Y, et al. A method to assess the protective efficacy of sunscreens against visible light-induced pigmentation. Photodermatol Photoimmunol Photomed. 2017;33(5):260-266. doi:10.1111/phpp.12325

10. Martini APM, Maia Campos PMBG. Influence of visible light on cutaneous hyperchromias: clinical efficacy of broad-spectrum sunscreens. Photodermatol Photoimmunol Photomed. 2018;34(4):241-248. doi:10.1111/phpp.12377

11. Dumbuya H, Grimes PE, Lynch S, et al. Impact of iron-oxide containing formulations against visible light-induced skin pigmentation in skin of color individuals. J Drugs Dermatol. 2020;19(7):712-717. doi:10.36849/JDD.2020.5032

12. Ezekwe N, Pourang A, Lyons AB, et al. Evaluation of the protection of sunscreen products against long wavelength ultraviolet A1 and visible light-induced biological effects. Photodermatol Photoimmunol Photomed. 2024;40(1):e12937. doi:10.1111/phpp.12937

13. Lim HW, Kohli I, Granger C, et al. Photoprotection of the skin from visible light-induced pigmentation: current testing methods and proposed harmonization. J Invest Dermatol. 2021;141(11):2569-2576. doi:10.1016/j.jid.2021.03.012

14. Kohli I, Ceresnie MS, Teklehaimanot F, et al. Objective assessment of color match for a universal tinted sunscreen on individuals with skin of color: a pilot study. Photodermatol Photoimmunol Photomed. 2024;40(1):e12941. doi:10.1111/phpp.12941

15. Bardhi R, Mokhtari M, Masood M, et al. Subjective and objective assessment of color match of universal tinted sunscreens in Fitzpatrick skin phototypes I-VI. Photodermatol Photoimmunol Photomed. 2024;40(5):e12992. doi:10.1111/phpp.12992

16. Passeron T, Lim HW, Goh CL, et al. Photoprotection according to skin phototype and dermatoses: practical recommendations from an expert panel. J Eur Acad Dermatol Venereol. 2021;35(7):1460-1469. doi:10.1111/jdv.17242

17. Rigel DS, Taylor SC, Lim HW, et al. Photoprotection for skin of all color: consensus and clinical guidance from an expert panel. J Am Acad Dermatol. 2022;86(suppl 3):S1-S8. doi:10.1016/j.jaad.2021.12.019

18. Torres AE, Awosika O, Maghfour J, Taylor S, Lim HW. Practical guide to tinted sunscreens. J Am Acad Dermatol. 2022;87(3):656-657. doi:10.1016/j.jaad.2021.12.040

19. Duteil L, Cadars B, Queille-Roussel C, et al. A new in vitro method to predict in vivo photoprotection of skin hyperpigmentation induced by visible light. J Eur Acad Dermatol Venereol. 2022;36(6):922-926. doi:10.1111/jdv.18034

20. Azim SA, Whiting C, Friedman AJ. Attitudes on, practices, and recommendations for visible light protection amongst dermatology practitioners. J Drugs Dermatol. 2024;23(11):965-971. doi:10.36849/JDD.8159

21. Dumbuya H, Yan X, Steeley K, et al. 51574 in vitro evaluation of tinted sunscreens protection against blue light. J Am Acad Dermatol. 2024;91(suppl 3):AB238.

22. Taylor SC, Alexis AF, Armstrong AW, Chiesa Fuxench ZC, Lim HW. Misconceptions of photoprotection in skin of color. J Am Acad Dermatol. 2022;86(suppl 3):S9-S17. doi:10.1016/j.jaad.2021.12.020

23. De La Garza H, Visutjindaporn P, Maymone MBC, Vashi NA. Tinted sunscreens: consumer preferences based on light, medium, and dark skin tones. Cutis. 2022;109(4):198-223. doi:10.12788/cutis.0504