Ultraviolet Protection From a Patented Amino Acid Complex Technology.

OBJECTIVE:   This study aimed to investigate the ultraviolet (UV) protection/repair benefits of a patented Amino Acid Complex (AAComplex). METHODS: I) AAComplex was incubated with dermal fibroblasts, with/without UVA, and collagen I was measured with a GlasBoxPlus device. II) A lotion, with/without AAComplex (1%) was applied topically to skin explants, following UVA irradiation, and quantified for health-related biomarkers (TNFalpha, histamine, and MMP-1). III) A broad spectrum sunscreen with SPF 46 and a skincare serum containing AAComplex (2%) were assessed using epidermal equivalents, in the presence of UV irradiation, for effects on IL-1alpha, thymine dimers, Ki-67, filaggrin and Nrf2. RESULTS: I) Collagen I synthesis in dermal fibroblasts was significantly decreased after UVA compared to without UV. The presence of AAComplex prevented this decrease. II) UVA irradiation of skin explants increased histamine, TNFα, and MMP-1. Hydrocortisone aceponate cream significantly decreases all 3 biomarkers. AAComplex contained lotion also significantly decreased all 3 biomarkers, the no AAComplex control lotion only reduced histamine. III) With the regimen of sunscreen + AAComplex contained skincare serum, the significant reduction in IL-1alpha was observed along with a complete recovery of Ki-67 and stimulation of filaggrin and Nrf2T. No thymine dimer positive cell was observed indicating the most positive skin impact from the regiment.  Conclusion: This research using different human skin models demonstrated that AAComplex can provide protection and damage repair caused by UV, at the ingredient level also when formulated in a serum or lotion formula. Skin may be best protected from UV damage when the regimen is used.   J Drugs Dermatol. 2024;23(5):366-375. doi:10.36849/JDD.7916.

The Knowledge, Attitudes, and Practices of Parents Regarding Sun Protection for Their Children.

OBJECTIVE: To evaluate the knowledge, attitudes, and practices of parents toward protecting their children against skin cancer and the sun. METHODS: This cross-sectional study was performed in Turkey from March through October 2022. The authors used a questionnaire investigating the parents' and children's characteristics, attitudes, and practices toward sun protection and the Skin Cancer and Sun Knowledge (SCSK) scale to collect data. RESULTS: Of 465 parents, 60.2% were women, 83.2% were light-skinned, 20.2% perceived their children as risk-free, 43.8% perceived their children as low risk in terms of skin cancer, 14.6% examined their children from head to foot, 62.3% applied sunscreen to their children, 9.7% made them wear long-sleeved clothing, 60.0% made them wear headgear, 61.1% made them remain in the shade or under a sunshade, and 32.3% made them wear sunglasses. The mean parental SCSK scale score was 14.3 ± 4.1. Scale scores were higher among those who perceived their children as being at high risk for skin cancer (P = .000), whose children had not experienced red or painful sunburn in the previous year (P = .000), and who informed their children about sun protection (P = .000). CONCLUSIONS: Although knowledge of skin cancer and solar protection was high, parental perception of the risk of skin cancer was very low, and attitudes toward skin examination were also very relaxed.

Understanding the perception of sunscreen utility in African Americans.

Dyschromia is a top diagnosis among African Americans (AA). Sunscreen is an essential part of its management, but AA have low sunscreen use. We sought to examine the perception of sunscreen utility in dyschromia and photoaging among patients who identify as AA or Black. This cross-sectional study recruited participants from the Case Western Reserve University Academic Dental Clinic. Participants completed an electronic survey that contained questions related to sunscreen use, knowledge of the sun's role in hyperpigmentation and photoaging, and whether sunscreen could be used for hyperpigmentation and photoaging. Of the 151 participants recruited, 63.6% (n = 96) were women and 36.4% (n = 57) were men. Consistent with previous reports, participants had lower sunscreen use (20.5%) than whites (43.5%). The majority of participants (80.1% and 58.3%, respectively) didn't attribute the sun to hyperpigmentation or photoaging. Participants with dark/brown spots were significantly more likely to not attribute the sun to hyperpigmentation than those without spots. (p = 0.003) Limitations for this study include its small sample size, recall and reporter bias, question misinterpretation, and lack of question neutrality. This study highlights the knowledge gap of a major contributing factor to dyschromia which in turn could be leading to their view of the decreased utility of sunscreen.

Sunscreen use and affordability attitudes based on ethnicity, socioeconomic status, and Fitzpatrick skin type.

IMPORTANCE: One in five Americans will develop skin cancer during their lifetime. While use of sunscreen can help prevent the development cutaneous cancer, regular use remains low nationwide. OBJECTIVE: To assess and better understand health care consumer preferences for sun protection products and perceived product accessibility and availability based on socioeconomic factors, race, and ethnicity. DESIGN: This quantitative survey study was conducted March through June of 2023. SETTING: Participants were recruited from two university family medicine clinical sites in the Buffalo, New York area, one located in a low and one located in a middle-to-upper socioeconomic neighborhood. PARTICIPANTS: Eligible participants were 18 years or older, fluent in English, and residents of the Buffalo, New York area. Surveys and consent forms were distributed by scripted verbal invitation, inviting all clinic patients who met eligibility criteria to participate. Participants were asked to self-report their racial/ethnic group as well as other demographic information including age, gender identification, household income, and household size. Information regarding sun exposure behaviors, and affordability/access was obtained using a combination of multiple choice and yes/no questions. A total of 405 participants were recruited. After excluding 235 incomplete responses, 170 surveys were available for analysis. INTERVENTIONS: None. MAIN OUTCOMES AND MEASURES: Our study aim was to expose health care consumer preferences as well as barriers to access based on socioeconomic factors, race, and ethnicity. RESULTS: Using a 25-question anonymous survey, 405 participants from two university family medicine clinical sites representing low- and middle-to-high-income neighborhoods, participated in the survey. 170 participants completed the survey questions and were included for analysis. Of those, 61.8% identified as female, 37.6% as male, and 0.6% as other. 51.2% of participants identified as lower income, 38.2% as middle-income, and 10.6% as upper income. The results of the survey revealed disparities in sunscreen use and affordability perceptions across demographic groups. Compared with Hispanics, Caucasians exhibited higher rates of sunscreen use (85 Caucasians, 7 Hispanics; p = 0.0073), prioritized SPF (95 Caucasians, 10 Hispanics; p = 0.0178), and were more likely to perceive sunscreen as unaffordable (6 Caucasians, 4 Hispanics; p = 0.0269). Analysis by Fitzpatrick Skin Type demonstrated differences in sunscreen utilization, with Types I-III using more compared to Types IV-VI (70 Types I-III, 51 Types IV-VI; p = 0.0173); additionally, Type I-III individuals were significantly more likely to cite cost as barrier to sunscreen purchase (40 Type I-III, 65 Types IV-VI; p < 0.0001). Moreover, lower-income individuals were significantly more likely to perceive sunscreen as unaffordable (12 lower-income, 1 middle & upper income; p = 0.0025) and cited cost as a barrier to purchase (46 lower-income, 59 middle & upper income; p = 0.0146) compared to middle-to-upper income counterparts. Though statistical significance was not established, respondents from middle & upper income groups reported higher sunscreen usage rates compared with their lower-income peers. CONCLUSIONS AND RELEVANCE: These findings highlight the importance of socioeconomic factors and ethnicity on accessibility to sunscreen and the impact of disparities in utilization among different ethnic and socioeconomic groups.

Perception of skin cancer risk and sun protective practices in individuals with vitiligo: a prospective international cross-sectional survey.

Many individuals with vitiligo are uncertain about their skin cancer risk, phototherapy risks, and recommended sun protective practices. This study examined the perceived skin cancer risk and sun protective practices among individuals living with vitiligo. A secondary objective was to understand where participants obtain this information. This was a prospective cross-sectional study. An online survey was distributed to vitiligo support group leaders globally who shared the survey with their members. Individuals over the age of 18 and with vitiligo were included. There were 209 survey respondents, the majority were between the ages 35-54 (45.5%, n = 95), female (70.8%, n = 148), White (66.0%, n = 138). Nearly half of respondents believed they were at increased risk of skin cancer because of their vitiligo (45.5%, n = 95) and nearly a quarter (22.5%, n = 47) believed that phototherapy increased their risk of skin cancer. Having vitiligo affected sun protective practices with less than a quarter (24.4%, n = 51) of respondents using sunscreen daily or often prior to their vitiligo diagnosis in comparison to the majority of respondents (60.3%, n = 126) using it after their vitiligo diagnosis. The three most common sources where patients obtained information were the internet and social media (46.4%, n = 97), vitiligo support groups (23.4%, n = 49), and dermatologists (20.6%, n = 43). Despite evidence indicating a decreased risk of skin cancer in individuals with vitiligo and supporting the safety of narrowband ultraviolet B phototherapy, many participants believed they were at an increased risk of skin cancer. Findings were sub-stratified and showed differences in sunscreen usage based on gender, skin color, and percent depigmentation. This study also found nearly half of respondents obtained information related to vitiligo from the internet and social media. The number of participants may limit the generalizability of the findings. Survey questionnaires are also subject to response bias. The findings from this study highlight demographic variations in sunscreen usage which may help guide the development of targeted interventions to improve sun protective behaviors among diverse populations with vitiligo. In addition, this study suggests certain sun protective practices and skin cancer risk perceptions may vary based on extent of depigmentation. Lastly, this study also demonstrates the internet and social media as a popular source for obtaining information, emphasizing the need for dermatologists to leverage various online communication channels to help disseminate accurate information.

A Practical Algorithm for Integrating Skincare to Improve Patient Outcomes and Satisfaction With Energy-Based Dermatologic Procedures.

BACKGROUND: Medical aesthetic procedures for facial antiaging with laser and energy-based devices (EBDs) are rapidly increasing, but standards integrating skincare before, during, and after these treatments are lacking. The algorithm for integrated skin care for facial antiaging treatment with EBDs aims to stimulate healing, reduce downtime, and improve comfort and treatment outcomes. METHODS: A panel of 8 global physicians employed a modified Delphi method and reached a consensus on the algorithm integrating skincare based on the best available evidence, the panel's clinical experience, and opinions. RESULTS: The algorithm has a pretreatment (starts 2 - 4 weeks before the procedure) and treatment (day of treatment) section, followed by care after the procedure (0 - 7 days) and follow-up care (1 - 4 weeks after the procedure or ongoing). Applying a broad-spectrum sunscreen with an SPF 50 or higher, combined with protective measures such as wearing a wide-brimmed hat and sunglasses, is recommended to protect the face from sun exposure. Dyschromia is a significant concern for those with skin of color (SOC). Clinicians may recommend skincare using a gentle cleanser and moisturizer containing vitamins C and E, retinoid, or other ingredients such as niacinamide, kojic acid, licorice root extract, azelaic acid, and tranexamic acid, depending on the patient's facial skin condition. CONCLUSION: Medical aesthetic procedures for facial antiaging with EBDs integrating skincare or topical treatments may improve outcomes and patient satisfaction. Topical antioxidants and free radical quenchers can combat photodamage and may offer a safe alternative to topical hydroquinone.  J Drugs Dermatol. 2024;23(5):353-359.     doi:10.36849/JDD.8092.

PRESOLRE: study protocol for a primary school-based, cluster randomised controlled trial of three sun exposure risk prevention strategies on Reunion Island.

INTRODUCTION: Reunion Island, a French overseas department, is located in the southern hemisphere, close to the Capricorn tropic. This island has a multicultural and multiethnic population of 860 000 inhabitants, a quarter of whom are at high risk of developing skin cancer due to intense ultraviolet radiation. Melanoma is responsible for the majority of skin cancer deaths. The early prevention of melanoma is based on sun protection in childhood, but French regulations are not adapted to the environmental conditions of this tropical region.The main objective of our study is to evaluate the effectiveness of three sun protection programs conducted in Reunionese primary schools through a pupil knowledge questionnaire. METHODS AND ANALYSIS: PRESOLRE is an interventional, open-label, cluster-randomised controlled trial, in four parallel arms, that is being conducted throughout 2022-2023 on Reunion Island. The trial design assumes an escalation interventional effect using: first, a control arm without proposed intervention (arm 1); second, an arm whose classes are encouraged to use the validated educational programme 'Living With the Sun' (LWS) (arm 2); third, an arm whose classes are encouraged to use both 'LWS' combined with 'Mission Soleil Réunion's sun protection awareness programme (arm 3); fourth, an arm benefiting from an intervention similar to arm 3, combined with the distribution of hats, sunglasses and sun creams (arm 4). In all, 1780 pupils from 18 classes of 20 pupils, on average, will be included. Randomisation applies to the classes of pupils (so defined as clusters). The primary outcome is based on the proportion of correct answers to the knowledge questions after the awareness programme, compared between the four arms using a linear mixed model with random intercept. ETHICS AND DISSEMINATION: The study obtained ethics approval in 2022 (ID: 2022-A00350-43). Results will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: NCT05367180.

Importance of treating acne sequelae in skin of color: 6-month phase IV study of trifarotene with an appropriate skincare routine including UV protection in acne-induced post-inflammatory hyperpigmentation.

BACKGROUND: Acne-induced hyperpigmentation (AIH) may accompany acne vulgaris (AV) inflammation in all skin phototypes. Trifarotene has shown depigmenting properties in vivo. This study evaluated trifarotene plus skincare because it is increasingly recognized that holistic AV management should include skincare and treatments. METHODS: This is a phase IV double-blind, parallel-group study of patients (13-35 years) with moderate AV and AIH treated with trifarotene (N = 60) or vehicle (N = 63) plus skincare regimen (moisturizer, cleanser, and sunscreen) for 24 weeks. Assessments included the AIH overall disease severity (ODS) score, post-AV hyperpigmentation index (PAHPI), exit interviews, photography, and acne assessments. Standard safety assessments were included. RESULTS: Trifarotene 50 µg/g cream improved significantly from baseline in ODS score versus vehicle (-1.6 vs. -1.1, P = 0.03) at Week 12, but scores were comparable between groups at Week 24 (primary endpoint). Trifarotene had a better reduction in PAHPI score at Week 24 (-18.9% vs. -11.3% vehicle, P < 0.01). Lesion count reductions were higher with trifarotene at Week 12 versus vehicle (P < 0.001) and at Week 24 (P < 0.05), as were IGA success rates versus vehicle at Weeks 12 (P < 0.05) and 24 (P < 0.05). Patients agreed that the skincare regimen contributed to less irritation, making treatment adherence easier. Photography showed improvements in pigmentation and erythema across all skin types. AEs were more common in the vehicle group versus trifarotene (30.2 vs. 16.7%, respectively). CONCLUSIONS: In all skin phototypes, there was more rapid improvement in the ODS and PAHPI scores with trifarotene by Weeks 12 and 24, respectively. The combination of trifarotene and skincare correlated with high patient satisfaction and adherence to the treatment protocol.

Protocol for a cluster-randomized trial of a school-based skin cancer preventive intervention for adolescents.

BACKGROUND: Adolescents infrequently use sun protection and engage in intentional tanning more frequently compared to other age groups, leading to increased ultraviolet radiation (UVR) exposure that heightens skin cancer risk across the lifespan. High schools are therefore an ideal setting for offering skin cancer preventive interventions. Yet, there are limited UVR protection interventions for high school students, especially those that are personalized, tested using randomized designs, and include long-term outcome assessment to determine the durability of intervention effects. METHOD: The Sun-safe Habits Intervention and Education (SHINE) cluster-randomized trial will test a novel, personalized intervention that targets high school adolescents' sun protection and tanning behaviors, and tracks their outcomes for up to one year following intervention. Enrolled high schools will be randomized to receive either the personalized SHINE intervention, which includes facial UVR photographs and sun protection action planning, or standard education using publicly available materials. Students in both conditions will receive information about skin cancer, sun protection, and skin self-examination. Outcome variables will include students' sun protection and tanning behaviors and sunburn occurrence. Potential moderators (e.g., race/ethnicity) and mediators (e.g., self-efficacy) will also be assessed and tested. CONCLUSIONS: This trial examines the efficacy of a personalized intervention targeting sun protection and tanning of high school students. The project will lead to new scientific understanding of the theoretical mechanisms underlying outcomes and moderators of the intervention effects, which will inform future intervention tailoring to meet the needs of vulnerable subgroups.

Management of Acne in Pregnancy.

Acne is one of the most common dermatological conditions to affect women of childbearing age, so it is important to consider the safety of long-term acne treatments on women who could become pregnant. In this review article, we clarify what management options are available to treat acne during pregnancy. Topical treatments, typically first-line for acne, such as azelaic acid, clindamycin, erythromycin, metronidazole, benzoyl peroxide, salicylic acid, dapsone, and retinoids, were reviewed. Systemic treatments, such as zinc supplements, cephalexin, cefadroxil, amoxicillin, azithromycin, erythromycin, and corticosteroids, typically second-line for acne, were also reviewed. Alternative treatments such as light therapy and cosmetic procedures were also evaluated. Due to recommendation of sunscreen utilization during acne treatments, sunscreen usage during pregnancy was also assessed. Management of acne during unplanned pregnancy was discussed in further detail regarding safety and adverse effects. Through summarized tables and examples of studies demonstrating safety and efficacy of treatments, the following is a resource for providers and patients to utilize for management of acne during pregnancy.

Prevalence of sunscreen use and sunburn in Greek athletes: a cross-sectional study.

BACKGROUND: Athletes participating in outdoor sports are in a high-risk category for prolonged sun exposure. This study investigates whether swimmers and beach volleyball athletes adopt appropriate measures to protect their skin from the sun. Sunscreens play a key role in protecting the skin from solar radiation and preventing premature aging. The study assesses the frequency of sunscreen use and the incidence of sunburn among athletes. METHODS: Athletes completed a self-administered questionnaire regarding their sun protection and exposure habits. Participants aged 9 to 60 years, engaged in swimming (N.=1047) and beach volleyball (N.=785), were included in this study. RESULTS: In the group of swimmers (N.=858), a notable percentage never used sunscreen, and among those who did, (N.=137), natural products were predominantly applied. Gender differences revealed a significantly higher sunscreen usage (P<0.001) among female swimmers compared to males. Among beach volleyball athletes, sunscreen use was notably higher (90%), with 55.6% applying natural sunscreen and 44.4% opting for non-natural alternatives. Regarding the incidence of sunburn, the occurrence among both male and female swimmers was observed to be very low. Among those with sunburn, females exhibited a significantly higher frequency than males (P<0.001). Conversely, in beach volleyball athletes, sunburn affected a higher percentage of males (49.8%) than females (43.9%). CONCLUSIONS: Sunscreen utilization is notably insufficient among athletes, reflecting a limited awareness of the potential risks associated with sun exposure, even though they frequently suffer from sunburn. This heightened susceptibility places them at an increased risk of developing skin lesions. Initiating and disseminating awareness campaigns that specifically emphasize the importance of sunscreen use within the outdoor sports community is imperative.

Assessment of prevalence of sunscreen use and related practices among people living in Saudi Arabia: A cross-sectional survey-based study.

BACKGROUND: The use of sunscreen significantly reduces the risk of skin cancer and helps maintain skin health; however, improper use can decrease its effectiveness. This study aimed to investigate the prevalence and factors associated with sunscreen use in Saudi Arabia as well as identifying areas of weakness in sunscreen practices. METHODS: A cross-sectional survey-based study was conducted with a diverse population sample in Saudi Arabia. Participants were asked about their sunscreen usage habits, motivations, and knowledge of proper application techniques. Demographic information, including age, gender, and skin type, were also collected. RESULTS: A total of 2321 individuals participated in the study. More than two-thirds of the participants reported using sunscreen either always, regularly, or often, primarily to maintain a light skin color and prevent skin cancer. Factors associated with sunscreen use included younger age (18-40 years old), female gender, history of sunburn, and fair skin. Despite the majority reporting healthy sun exposure habits, several shortcomings were identified in sunscreen practices, including incorrect application and suboptimal reapplication frequency. CONCLUSION: While sunscreen use is common among the study population, there is a need for improved education on proper application techniques. National awareness campaigns, especially those utilizing popular social media and digital platforms in Saudi Arabia, should focus on disseminating accurate sunscreen use guidelines to maximize sun protection and skin health.

Enhanced Sunscreen Effects via Layer-By-Layer Self-Assembly of Chitosan/Sodium Alginate/Calcium Chloride/EHA.

The sunscreen nanocapsules were successfully synthesized by the way of layer-by-layer self-assembly using charged droplets (prepared by emulsification of LAD-30, Tween-80 and EHA (2-Ethylhexyl-4-dimethylaminobenzoate)) as templates. Chitosan/sodium alginate/calcium chloride were selected as wall materials to wrap EHA. The emulsions with the ratio of Tween-80 to EHA (1:1) were stable. A stable NEI negative emulsion can be obtained when the ratio of Tween-80 and LAD-30 was 9:1. Chitosan solutions (50 kDa, 0.25 mg/mL) and sodium alginate solutions (0.5 mg/mL) were selected to prepare nanocapsules. The nanocapsules were characterized via some physico-chemical methods. Based on the synergistic effects of the electrostatic interaction between wall materials and emulsifiers, EHA was effectively encapsulated. DLS and TEM showed that the sunscreen nanocapsules were dispersed in a spherical shape with nano-size, with the increasing number of assembly layers, the size increased from 155 nm (NEI) to 189 nm (NEII) to 201 nm (NEIII) and 205 nm after solidification. The release studies in vitro showed sustained release behavior of the nanocapsules were observed with the increase of the number of deposition layers, implying a good coating effect. The sunscreen nanocapsules could control less than 50% the release of EHA after crosslinking of calcium chloride and sodium alginate, which also could effectively avoid the stimulation of the sun protection agent on the skin.

No Negative Association Between Sun Protection and Bone Health.

According to this study: The practice of sun protection is not associated with bone-related health complications, such as an increased risk of osteoporotic fractures.Sun protection should be encouraged for all patients, including those at risk for decreased bone mineral density and fractures.

Protective effects of gallocatechin gallate against ultraviolet B induced skin damages in hairless mice.

Epigallocatechin gallate (EGCG) has the effect to protect skin from ultraviolet B (UVB) induced damages, but it is unstable under ambient conditions, being susceptible to become brown in color. Gallocatechin gallate (GCG), an epimer counterpart of EGCG, is more stable chemically than EGCG. The potential effects of GCG against UVB-induced skin damages has not been available. The objective of this study was to investigate the protective effects of GCG against UVB-induced skin photodamages. GCG was topically applied on the skin of hairless mice at three dosage levels (LL, 12.5 mg/mL; ML 25 mg/mL; HL, 50 mg/mL), with EGCG and a commercially available baby sunscreen lotion SPF50 PA+++ as control. The mice were then irradiated by UVB (fluence rate 1.7 µmol/m2 s) for 45 min. The treatments were carried out once a day for 6 consecutive days. Skin measurements and histological studies were performed at the end of experiment. The results show that GCG treatments at ML and HL levels inhibited the increase in levels of skin oil and pigmentation induced by UVB irradiation, and improved the skin elasticity and collagen fibers. GCG at ML and HL levels inhibited the formation of melanosomes and aberrations in mitochondria of UVB-irradiated skin in hairless mice. It is concluded that GCG protected skin from UVB-induced photodamages by improving skin elasticity and collagen fibers, and inhibiting aberrations in mitochondria and formation of melanosomes.

Algae Metabolites as an Alternative in Prevention and Treatment of Skin Problems Associated with Solar Radiation and Conventional Photo-protection

Abstract The histological structure and biochemistry of the skin is affected by solar radiation having adverse effects ranging from sunburns, premature aging that includes wrinkles, spots, dryness, and loss of collagen to cancer development. The skin has defense mechanisms to prevent damage caused by radiation, but when radiation exposure is excessive these mechanisms are not strong enough to protect the skin. The use of sunscreen is the most common practice of photo- protection. The active ingredients of these cosmetic protective formulations are generally from synthetic origin and have presented several drawbacks at the level of photo-stability, systemic absorption and can generate contact and photo-contact dermatitis. This review illustrates skin solar radiation problems, common sunscreen ingredients limitation and mentions how algae can be an alternative according to studies that have evaluated the photo-protective potential of extracts and compounds isolated by different techniques.

Adverse Reactions to Sunscreens.

Adverse reactions to sunscreens are uncommon in relation to their widespread use [Loden et al. Br J Dermatol. 2011;165(2):255-62; Jansen et al. J Am Acad Dermatol. 2013;69(6):867 e861-814; quiz 881-862] and can be related to both active and inactive ingredients in sunscreen products [DiNardo et al. J Cosmet Dermatol. 2018;17(1):15-19; Barrientos et al. Contact Dermatitis. 2019;81(2):151-52]. Pathogenetically, the main cutaneous adverse reaction patterns to sunscreens can be divided into allergic and irritant contact dermatitis, phototoxic and photoallergic contact dermatitis, contact urticaria, and, in solitary cases, anaphylactic reactions [Lautenschlager et al. Lancet. 2007;370(9586):528-37]. A summary is provided in Table 1. Nearly all adverse effects due to active sunscreen ingredients reported to date are related to the organic UV filters, which are sometimes also referred to as "chemical UV filters." This imbalance is attributable to the lipophilic character and small molecular size of the organic UV filters that allow skin penetration, which is the basic requirement to initiate the sensitization [Stiefel et al. Int J Cosmet Sci. 2015;37(1):2-30]. In contrast, cutaneous adverse reactions to inorganic UV filters, initially termed "physical UV filters" owing to their firstly known "physical" mechanism of action through reflection and scattering [Stiefel et al. Int J Cosmet Sci. 2015;37(1):2-30], are only reported by case reports. Neither zinc oxide nor titanium dioxide possesses relevant skin-irritating properties or sensitization potential [Lau-tenschlager et al. Lancet. 2007;370(9586):528-37]. Adverse reactions to UV filters currently approved in the European Union as listed in the Annex VI (updated November 7, 2019) are summarized in Table 2.

Challenges in Sun Protection.

Since time immemorial, people protected themselves from solar radiation. Limiting time in the sun by seeking shade or wearing clothing was a matter of course. In the early 20th century, tanned skin - a result of exposure to sunlight - was associated with good health. At the same time, however, one also had to protect oneself against the potential of excessive exposure to avoid sunburns. Around 1945, the first sunscreen products for protection against solar radiation became available. In the years to follow and up to the recent past, a vast number of different sunscreen filters were developed and incorporated into a wide variety of product formats. Frameworks regulating filter substances and preparations and methods to characterize sunscreen products' performance parameters were developed. Over the past 50-70 years, the perception regarding the tasks of sunscreen products changed several times. It was initially promoted as a lifestyle product and had the task of preventing sun-related erythema (tan without burn). Later, the prevention of skin cancer was added. Only in recent times, sunscreen products have been increasingly advertised and perceived as beauty and lifestyle products again. Also, the use of sunscreen products for antiaging purposes is now commonplace. The different intended purposes (averting harm and prevention) and the widespread use of topical sunscreen products have promoted many investigations and generated a vast and ongoing need for consumer and patient information and education. In the following review, we analyze and discuss current topics from conflicting areas, such as sun protection products (e.g., ideal sun protection products, sun protection metrics), product safety (e.g., nanoparticulate sunscreen filters, regulatory issues), application in everyday life (e.g., wish to tan, vulnerable cohorts), as well as controversies and future challenges (e.g., risks and benefits of UV radiation).