Sun Damage Research Articles

830 Gene-UV interactions determining sun damage

Skin cancers that form after ultraviolet (UV) light exposure occur more frequently than any other cancer type, and in the case of melanoma, they are often fatal. UV exposure induces these cancers through DNA mutation, and causes damage such as aging, solar elastosis and hyperpigmentation. Ultraviolet (UV) facial photographs obtained using the Canfield Visia UV camera may detect sub-visible skin damage caused by UV exposure, and could be used to help track and minimize the accumulation of sun damage. Nevertheless, it is not known how these skin damage scores relate to melanoma risk factors such as UV exposure history or to genetic factors that may predispose to their formation. We are currently following a group of 1,145 children with annual skin exams and telephone interviews and collecting a comprehensive longitudinal set of skin cancer risk factor information. We have used facial UV photography to generate a sun damage score on 550 children. Here we report that facial sun damage scores correlate with known skin cancer and melanoma risk factors such as UV exposure history and genetic risk factors such as MC1R, IRF4, and TYR (among others). Thus we show that UV photography may be used to accurately identify, based on genetic makeup, sun damage associated with an individual’s UV exposure history. Moreover, we report those loci that interact with sun exposure history and those that act in an additive fashion to maximize the effects of UV exposure on sun damage. We are working to determine if this technology may be used to identify unique high risk groups that may benefit from dermatologic surveillance and preventive action.

The relative role of cognitive and emotional reactions in mediating the effects of a social comparison sun protection intervention

Objective: This experiment examined the cognitive and emotional impact of two social comparison-based sun protection interventions in a sample of Southern California college students (N = 223). One of the interventions employed comparison UV photos of peers who had either much more (downward social comparison) or much less (upward social comparison) skin damage than did participants themselves. The second intervention consisted of descriptive norms information suggesting that a large majority of the participants’ peer group regularly protect their skin from the sun.Design: Participants were randomly assigned to one of eight conditions in a 4 (Social Comparison Information: no photo vs. no comparison photos vs. upward comparison photos vs. downward comparison photos) × 2 (Descriptive Norms Information: Received vs. not received) design.Main Outcome Measures: Emotional reactions (e.g. worry, embarrassment, relief) and sun-related cognitive reactions (perceived susceptibility, sun protection intentions) were assessed immediately. Sun protection behaviours were assessed in a surprise telephone follow-up five weeks following the intervention.Results: The results demonstrated that the combination of seeing photos of peers who had very little sun damage and learning that a majority of one’s peers engage in regular sun protection resulted in reliably greater subsequent sun protection than all other conditions. Further, there was relatively direct evidence that both negative emotional reactions and sun protection intentions mediated this effect.Conclusions: These findings add to the growing literature suggesting the importance of thoroughly examining the role of emotions in health behaviour decisions. Both theory and intervention efficacy would benefit from a better understanding of the relative role of cognitions and emotions in behaviour change.

Sunscreens and their properties for skin protection from solar radiation

Extensive promotion on the internet and in the media has led to an increase in public awareness that too much exposure to sun can cause photodamage and skin cancers. However, there are gaps in knowledge regarding the selection of the right sunscreen, recommended dose and daily application schedule. The labels of sunscreens are often difficult to understand and consumers remain unaware about the potential photodamage caused by infrared (IR) and high-energy visible light (HEVL). Patients are becoming increasingly conscious about skin health and aesthetics, but they often seek help only after a significant amount of sun damage has already occurred. There are still many discrepancies related to the correct method of sunscreen application and the best times for reapplication. Much more research is needed to study the harmful effects of sunscreen ingredients on systemic absorption, if any, in areas such as safety in pregnant and breastfeeding women, and the relationship to various skin cancers and diseases. This article discusses the types and formulations of sunscreens for ultraviolet light, IR and HEVL protection. It also covers sunscreen labels, application techniques, recommended doses, safety and possible health hazards, related controversies, product shelf life and the importance of patient education.

The importance of patient-centred care to overcome barriers in the management of actinic keratosis.

Visible actinic keratosis (AK) lesions and subclinical (non-visible) sun damage in the field of cancerization are associated with risk of both non-melanoma skin cancer, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC), and, more rarely, melanoma. As the incidences of AK and skin cancer are increasing, effective prevention and treatment of AK is essential to minimize disease burden and improve patient quality of life. Currently, AK lesions are often left untreated and field therapies are underused. Patient-centred care, with a focus on the patient-physician relationship, has proven cost-effective, and improved clinical outcomes and patient satisfaction in a number of therapy areas. Strategies for applying patient-centred care to AK are warranted. Existing barriers to the effective treatment of AK were identified and patient-centric strategies to overcome each barrier were discussed. Barriers to effective AK treatment include poor disease awareness (for both patient and physician), concerns associated with the cosmetic effects of treatment, treatment-related side effects, cost perceptions for lesion-directed vs field-directed therapies, and inadequate adherence, particularly with long treatment duration. Overcoming these barriers will involve patient and physician education that promotes: disease prevention and awareness; the importance of self-examination; an understanding of treatment options; and the importance of adherence to treatment. To maximize its effectiveness, education should be delivered within a patient-centric framework, where the relationship between patient and physician is built on effective communication, empathy and a feeling of partnership. Patient-centric care, including patient education, is key to overcoming the barriers associated with effective AK treatment.

The importance of treating the field in actinic keratosis.

Actinic keratoses (AKs) are intraepithelial atypical proliferations of keratinocytes that develop in skin that has undergone long-term exposure to ultraviolet radiation. Given the ageing population and an increasing prevalence of AK, the socio-economic burden of AK is likely to rise over the coming years. Areas of subclinical (non-visible) sun damage in the periphery of visible AK lesions contain the same genetic changes as those found in the lesions themselves, and are known as areas of field cancerization. AK lesions and the field are associated with an increased risk of skin cancer, including invasive squamous cell carcinoma. Although effective in clearing visible AK, lesion-directed therapies do not address field cancerization and can lead to high recurrence rates. In contrast, field-directed therapies, such as ingenol mebutate, imiquimod and diclofenac, can clear both visible and subclinical AK lesions and reduce the development of new lesions in the treated field. Additionally, preclinical studies suggest that field therapy may prevent or delay the recurrence of non-melanoma skin cancer. AK treatment guidelines now recognize the importance of treating the field in patients with AK, and adaptation of treatment guidelines into clinical practice is warranted. Physician and patient education around the consequences of leaving the field of cancerization untreated is necessary in order to reduce the increasing burden associated with AK.

Further assessment of exome-wide UVR footprints in melanoma and their possible relevance.

C>T substitutions at dipyrimidine sites dominate the melanoma genome. We recently analyzed the exomes of spontaneous and neonatal UVR-induced murine melanomas, noting a dramatic change in the genomic footprint at C>T substitutions in the latter. Here we re-analyzed published exome-wide footprints in human melanomas stratified in terms of likely previous sun exposure. Acral and mucosal melanomas were heterogeneous in terms of base substitution types, but most C>Ts occurred in the context of 3'G, probably resulting from spontaneous deamination of the cytosine. C>Ts in sun-exposed melanomas were statistically different from acral/mucosal lesions only in preferring an adjacent 5'T and 3'C. Pyrimidine dimer adducts can form between any pyrimidine (TT, TC, CT, CC). Hence in melanoma C>Ts are overwhelmingly induced at TC or CC photoproducts, or, there are peculiarities in DNA repair that favor the mutation of cytosines with these two pyrimidines adjacent. If melanoma UVR footprints at C>Ts reflect a specific dimer type (eg, 6-4 photoproduct or cyclobutane pyrimidine dimer), these could be removed post UVR, for instance using photolyases, to potentially reduce melanoma risk. If specific modes of DNA repair and/or replication cause these footprints, methodically downregulating selected DNA polymerases in UVR-induced animal models of melanoma, combined with exome sequencing, could begin to assess this. Finally, a preponderance of TpCpC as opposed to NpCpG at C>Ts exome-wide is likely to be a good indicator of whether a melanoma has incurred even a small amount of sun damage. This information will assist epidemiological studies in predicting individual levels of sun exposure.

A Novel Actinic Keratosis Field Assessment Scale for Grading Actinic Keratosis Disease Severity.

Actinic keratosis (AK) lesions are surrounded by field cancerization (areas of subclinical, non-visible sun damage). Existing AK grading tools rely on AK counts, which are not reproducible. An Actinic Keratosis Field Assessment Scale (AK-FAS) for grading the severity of AK/field was developed. Standardized photographs of patients representing the full range of AK severity were collected. Six investigators independently rated each photograph according to 3 criteria: AK area (total skin area affected by AK lesions), hyperkeratosis and sun damage. Inter-rater reproducibility was good for all 3 criteria. Validation of the AK-FAS showed good reproducibility for AK area and hyperkeratosis, even for dermatologists untrained on use of the scale. In conclusion, the AK-FAS is objective, easy to use and implement, and reproducible. It incorporates assessment of the entire field affected by AK instead of relying on lesion counts. Use of the AK-FAS may standardize AK diagnosis, making it relevant to routine clinical practice.

QUEM SE AMA, PROTEGE SUA PELE: ORIENTAÇÕES FARMACÊUTICAS NA PREVENÇÃO CONTRA O CÂNCER DE PELE

This study aimed at characterizing the participants and showing the educational materials of a university extension activity on photoprotection [A1]. The campaign was devised by Brazil’s National Forum of Teaching Pharmacies (FNFU) and involves several universities throughout the country. Questionnaires on the regular use of photoprotective products by students enrolled in various undergraduate courses, university employees and outsourced workers were handed to all the people who visited the site of the campaign “If you love yourself, you will protect your skin from sun damage: pharmaceutical guidance in the fight against skin cancer”. Out of the 235 respondents, 40.85% reported using photoprotective products on a daily basis, and the reasons given by most of those who did not do it were forgetfulness, lack of time and the high cost of these products. Therefore, the study collected important information on the use of sunscreen and on the level of information of the academic community about this issue.

INFLUENCIA DEL USO DE MALLA PERLA Y ROJA EN LAS CONDICIONES MICRO-CLIMÁTICAS, DAÑO POR SOL Y DESARROLLO DE COLOR DE FRUTOS EN HUERTOS DE MANZANOS CVS. GALA Y FUJI

RESUMEN El daño por sol y la falta de color de frutos producida por el exceso de radiación solar y altas temperaturas es el mayor problema productivo en los huertos de manzano en Chile. El objetivo de esta investigación fue evaluar el uso de mallas de colores como herramienta para el control de daño por sol y mejorar la coloración en manzanas. Durante la temporada 2012-13 y 2013-14 un huerto de manzanos ´Fuji´ y ´Gala´ fue cubierto con mallas de color Roja y Perla al 20% de sombreado, dejando árboles sin cubrir como control. Se realizó un registro de la temperatura del aire y fruto (ºC), humedad relativa (%) y radiación fotosintéticamente activa total (PARtotal) y difusa (PARdifusa) (µmol m-2 s-1). Al momento de cosecha se cuantificó la incidencia de daño por sol con escala visual (%) y el color de frutos a través de un equipo Color Hunter. En promedio, para ambas temporadas, la malla Roja redujo la transmisión de PARtotal en un 21%, mientras que la malla Perla en un 17%. La cantidad PARdifusa fue en promedio un 15% superior bajo la malla Perla que la malla Roja, incrementando con ello el desarrollo de color rojo de frutos en el cultivar Fuji. Durante la temporada 2012/13 ambas mallas redujeron en un 26% y 44% el daño por sol en frutos para los cultivares Gala y Fuji, respectivamente. Durante la temporada 2013/14 las mallas no redujeron significativamente el daño por sol en los frutos. Los resultados de este estudio sugieren que la malla Perla provee de mejores condiciones de luz para el desarrollo de color rojo de frutos en huertos de manzanos. No obstante, bajo las condiciones climáticas de Chile, ambas mallas (Roja y Perla) presentan una efectividad solo relativa para el control de golpe de sol en manzanas.

Daily Use of a Facial Broad Spectrum Sunscreen Over One-Year Significantly Improves Clinical Evaluation of Photoaging

Sunscreens are known to protect from sun damage; however, their effects on the reversal of photodamage have been minimally investigated. The aim of the prospective study was to evaluate the efficacy of a facial sun protection factor (SPF) 30 formulation for the improvement of photodamage during a 1-year use. Thirty-two subjects applied a broad spectrum photostable sunscreen (SPF 30) for 52 weeks to the entire face. Assessments were conducted through dermatologist evaluations and subjects' self-assessment at baseline and then at Weeks 12, 24, 36, and 52. Clinical evaluations showed that all photoaging parameters improved significantly from baseline as early as Week 12 and the amelioration continued until Week 52. Skin texture, clarity, and mottled and discrete pigmentation were the most improved parameters by the end of the study (40% to 52% improvement from baseline), with 100% of subjects showing improvement in skin clarity and texture. The daily use of a facial broad-spectrum photostable sunscreen may visibly reverse the signs of existing photodamage, in addition to preventing additional sun damage.

Skincare Bootcamp: The Evolving Role of Skincare.

Background:Although cosmetic procedures have a significant impact on certain aspects of aging, such as deep, wrinkling, sagging, and volume loss, they fail to address the overall quality of the skin.Methods:Daily skincare routines potentially can have a significant long-term impact on the overall quality of a person’s complexion.Results:By expanding our product knowledge, we can help our patients individualize their at-home skincare routine using effective products and ingredients designed to address their specific skin concern and support the professional care we deliver.Conclusions:Here, we discuss the types of products and ingredients suitable for the most common dermatologic concerns, from wrinkling to skin sensitivity, acne to sun damage.

Oral photoprotection: reducing damage from ultraviolet light and inflammation

Clinicians practising within the medical aesthetic sector commonly advise patients to apply topical sun protection factor to protect their skin from sun damage. However, it is a little known fact that certain orally consumed nutrients can play an important role in helping to protect the skin from damage induced by ultraviolet (UV) light exposure. When provided at therapeutic doses, antioxidants, probiotics, B vitamins and fish oils have all been shown to exert photoprotective effects. The mechanisms by which these nutrients can help to protect the skin against UV radiation are many and varied. They include protecting against UV-induced free radical damage and inflammation, as well as modulating cutaneous immune function. In this review, the author discusses the specific nutrients that can provide protoprotection, which are widely available in supplemental form to both aesthetic practitioners and patients alike.

Association Between Confocal Morphologic Classification and Clinical Phenotypes of Multiple Primary and Familial Melanomas.

The improved knowledge of clinical, morphologic, and epidemiologic heterogeneity of melanoma in the context of multiple primary and familial melanomas may improve prevention, diagnosis, and prognosis of melanoma. To characterize reflectance confocal microscopy (RCM) morphologic patterns of melanomas in multiple primary and familial melanomas. In this cross-sectional, retrospective study, patients in a hospital-based referral center were recruited from March 1, 2010, through August 31, 2013; data analysis was conducted from September 1, 2013, through May 31, 2014. Consecutive primary melanomas, documented by dermoscopic and confocal examination, from multiple primary and familial melanomas with known CDKN2A mutational status were studied. Epidemiologic, genetic, dermoscopic, and histologic data were evaluated according to an RCM morphologic classification: dendritic cell, round cell, dermal nest, combined, and nonclassifiable types. Fifty-seven melanomas from 50 patients (28 women [56%] and 49 white patients [98%]) were included: 23 dendritic cell (40%), 21 round cell (37%), 2 dermal nests (4%), 2 combined (4%), and 9 nonclassifiable (16%). The median (SD) age of the participants was 53.0 (16.9) years (interquartile range, 41.8-71.2 years), and the median (SD) age at the first melanoma was 46.0 (17.1) years (interquartile range, 35.8-61.5 years). Dendritic cell melanoma was characterized by older age at diagnosis, phototypes 2 and 3, more intense solar exposure, and moderate to severe solar lentigines; it was the most prevalent confocal type in facial lesions and was associated with the lentigo maligna histologic subtype. Round cell melanomas were identified more often in the familial context and in individuals with phototype 1 skin types; RCM features, such as junctional thickening, dense dermal nests, and nucleated cells within papillary dermis, were more frequently found in this subtype. Dermal nest and combined melanoma were associated with the absence of pigmented network on dermoscopy and thicker tumors on histologic analysis. Nonclassifiable type was associated, by RCM, with the absence of pagetoid cells on confocal examination and lower frequency of marked atypia on melanocytes in the basal cell layer; it presented with lower ABCD Total Dermoscopy Scores and RCM scores compared with the other types. CDKN2A mutation carriers may develop any RCM type of melanoma. Different routes to develop melanoma can be identified according to RCM morphologic classification, with dendritic cell melanomas being associated with chronic sun damage and round cell melanoma with early age at onset and phototype 1 in the context of multiple primary and familial melanomas. The morphologic expression of melanomas via dermoscopy and confocal examination varies according to differences in tumor stage and biological behavior.

Early detection of sun injury on apples (Malus domestica Borkh.) through the use of crop water stress index and chlorophyll fluorescence

Sun-injury (=sunburn) on apples is an important physiological disorder affecting all cultivars grown in semi-arid climates. Both, high light and elevated temperatures during the fruit-growing season are responsible for the symptoms. Therefore, a crop water stress index (CWSI), calculated from infrared images, and chlorophyll fluorescence were assessed as early predictors, when no symptoms of sun-damage were yet visible. Fifty fruit of each cv. (Royal Gala, Granny Smith, Fuji) were tagged at 50days after full bloom (DAFB) in different orchards. Infrared images were taken weekly and used for CWSI calculation. A similar number of fruit (Royal Gala, Fuji) were tagged after 80 DAFB for chlorophyll fluorescence measurements carried out every 2 weeks.The proposed CWSI was able to predict the occurrence of severe sunburn symptoms in Granny Smith apples as early as 86 DAFB, 42days before symptoms were visible. In Fuji, this occurred as early as 122 DAFB, 25days prior visible symptoms. The threshold value of CWSI required for sunburn development on the fruit was 0.5. The maximum quantum efficiency of photosystem II (Fv/Fm) was also able to detect early sun damage, at 100 DAFB, before symptoms appearance, with a threshold value of 0.6. The results would imply that early events in photooxidative stress leading to sun injury have a profound effect on tissue physiology and biochemistry, which can be assessed using chlorophyll fluorescence and a thermography-based index, such as the CWSI. Both, the CWSI and Fv/Fm ratio could be used as non-destructive, fast and reliably field tools to monitor sun-injury when no symptoms have yet developed.

Fruit surface temperature of red-blushed pear: threshold for sunburn damage

ABSTRACTPear fruit are subject to sun damage from high fruit surface temperature (FST). Threshold FST for the occurrence of sunburn are currently unknown and basic relationships between FST of pears and weather parameters have not been reported. Such knowledge is needed to aid implementation of management practices and improve orchard design to minimise sunburn. This paper reports relationships between pear FST and weather conditions. Continuous monitoring of FST and observations of sunburn damage enabled determination of threshold FST for the development of sunburn. Threshold FST for sunburn damage on ‘ANP-0131’ (Deliza®) pears was estimated to be 47.1 °C. Use of FST thresholds to improve mitigation of sunburn is discussed.

Assessment of dermatoheliosis with reflectance confocal microscopy

Dermatoheliosis increases the risk of developing malignant epithelial skin tumors and locates on aesthetically critical areas. Therefore there is a need for noninvasive objective technique capable of in vivo assessing the cumulative effect of UV-radiation, the severity ofphotoaging and the risk of epithelial skin cancer. In our study we aimed to determine the morphological changes occurring on photoaged skin and early signs of keratinocyte dysplasia by means of reflectance confocal microscopy (RCM). Material and method. The samples of facial skin of 40 volunteers from distinct groups, determined by Glogau scale (grades I-IV), have been examined with RCM. Results. The presence of irregular honeycomb pattern is increasing with progressing of dermatoheliosis. Mottled pigmentation and polycyclic papillary contours were determined in grade II-IV Glogau individuals, in the number of cases there were not demonstrated any pathological skin changes in analyzing area. Dermal structures are significantly transforming: reticulated collagen fibers are replacing with coarse collagen structures, huddled collagen and curled bright structures. RCM is capable of identifying early signs of sun damage and keratinocyte dysplasia in skin in the absence of any clinically visible symptoms.

How hail netting reduces apple fruit surface temperature: A microclimate and modelling study

High fruit temperatures compromise fruit quality and cause production losses in the apple industry. In south-eastern Australia, orchardists have begun investing in netting because of empirical evidence that it reduces these losses, but the magnitude of its effect and mechanisms responsible have not yet been quantified. Models of fruit temperature based on meteorological conditions could inform the design of netting structures, and improve tactical management to reduce sun damage through treatments such as protective sprays and the use of overhead irrigation to cool fruit. The objectives of this study were firstly to measure the effect of netting on fruit surface temperature, and secondly to test the thermodynamic Smart-Sinclair model. The study was conducted near Shepparton, Victoria, in an orchard where there were adjacent netted and non-netted sections. During late afternoon when sun damage normally occurs, netting was able to reduce the median fruit surface temperature by 1.5–2.0°C, but there was a greater reduction in maximum fruit surface temperature of 4.0°C. The model required calibration to account for turbulence in the transfer of heat from fruit to the surrounding air. The optimised model was able to predict fruit surface temperature with a root mean square error of 2–4°C. The mechanism for the reduction in fruit surface temperature was by reducing the intensity of the solar beam in the late afternoon by interception and scattering, which more than offset the potential fruit heating effect of netting that occurs through a reduction in internal orchard wind speed.

MAL Daylight Photodynamic Therapy for Actinic Keratosis: Clinical and Imaging Evaluation by 3D Camera.

Non-melanoma skin cancer is the most common skin cancer with an incidence that varies widely worldwide. Among them, actinic keratosis (AK), considered by some authors as in situ squamous cell carcinoma (SCC), are the most common and reflect an abnormal multistep skin cell development due to the chronic ultraviolet (UV) light exposure. No ideal treatment exists, but the potential risk of their development in a more invasive form requires prompt treatment. As patients usually present with multiple AK on fields of actinic damage, there is a need for effective, safe, simple and short treatments which allow the treatment of large areas. To achieve this, daylight photodynamic therapy (DL-PDT) is an innovative treatment for multiple mild actinic keratosis, well tolerated by patients. Patients allocated to the PDT unit, affected by multiple mild−moderate and severe actinic keratosis on sun-exposed areas treated with DL-PDT, were clinically evaluated at baseline and every three months with an Antera 3D, Miravex© camera. Clinical and 3D images were performed at each clinical check almost every three months. In this retrospective study, 331 patients (56.7% male, 43.3% female) were treated with DL-PDT. We observed a full clearance in more than two-thirds of patients with one or two treatments. Different responses depend on the number of lesions and on their severity; for patients with 1–3 lesions and with grade I or II AK, a full clearance was reached in 85% of cases with a maximum of two treatments. DL-PDT in general improved skin tone and erased sun damage. Evaluating each Antera 3D images, hemoglobin concentration and pigmentation, a skin color and tone improvement in 310 patients was observed. DL-PDT appears as a promising, effective, simple, tolerable and practical treatment for actinic damage associated with AK, and even treatment of large areas can be with little or no pain. The 3D imaging allowed for quantifying in real time the aesthetic benefits of DL-PDT’s increasing compliance.

Primary Care Health Professionals’ Knowledge of Sun Safety

ABSTRACT It is well known that sun and ultraviolet exposure can increase the risk of skin cancers in individuals (New York State Department of Health, 2014). However, there is a lack of guidelines in primary care regarding routine skin examination for adolescents and insufficient evidence regarding sun safety education for all patients and their families in healthcare settings. Our study aimed to assess knowledge on sun safety and sun damage among healthcare professionals by surveying 50 family nurse practitioner students enrolled in the course of Diagnosis and Management II at Columbia University School of Nursing in the Year 2015. We hypothesized that the knowledge of sun safety will increase with our intervention of an educational pamphlet to participants. Our results reflect a lack of knowledge regarding sun safety among healthcare professionals. Despite the limitations in our study, it did show that pamphlet distribution on sun safety education does increase healthcare professionals’ knowledge. With increased awareness of sun safety in primary care health, health professionals will have the ability to influence individuals on positive habits that can prevent the development of skin cancer.

Reducing the risk of skin cancer: The importance of sun protection at school

Most skin cancers, which are among the most common malignancies in the UK, follow excessive exposure to ultraviolet (UV) radiation and are, therefore, potentially preventable. In general, most people receive much of their lifetime UV exposure as children and adolescents, and sun damage during childhood markedly increases the risk of developing skin cancer in later life. This article considers elements that nurses could include in their school's safe sun policies and when educating pupils, parents and staff. In addition, school nurses could encourage the curriculum and timetable to consider sun protection and inform architectural discussions. Sunlight is, however, the main source of vitamin D in the UK. People who avoid all sun exposure should consider having their serum vitamin D measured. If levels are reduced or deficient, nurses could consider suggesting increasing vitamin D intake.