Overview on vitamin D and sunbed use

An Epidemiological Update on Indoor Tanning and the Risk of Skin Cancers

Indoor tanning (sunbeds, solarium) uses artificial ultraviolet radiation (UVR) to stimulate cosmetic tanning of the skin. Indoor tanning has been officially classified as a human carcinogen in 2009 by the International Agency for Research on Cancer of the World Health Organization (WHO). The differences in the prevalence of sunbed use across countries and over the years highlight underlying legislative, climatic, and cultural differences. Indoor tanning-seeking behaviors may be driven by motivations for an appealing appearance, largely influenced by gender and age, and several misconceptions that a prevacation tan safeguards the skin, that sunbeds can be used to treat acne or to increase vitamin D, or that tanning is a healthy habit. This review provides an epidemiological update on the prevalence of sunbed use, who tends to use sunbeds and why, and details the current evidence on the association of sunbeds with skin cancers, including cutaneous melanoma, basal cell carcinoma (BCC), and cutaneous squamous cell carcinoma (cSCC). A statistically significant higher risk of cutaneous melanoma, BCC and cSCC with the use of sunbeds has been consistently demonstrated. This risk of skin cancer is even higher with the more frequent use of sunbeds, underscoring a dose-response relationship, and in those first exposed to sunbeds at a younger age. Preventive measures against sunbed use include legislation restricting sunbed use, educational campaigns to inform and discourage from indoor tanning, as well as using the internet, online advertising messages and the social media to reach larger audiences and to promote an untanned appearance.

Vitamin D and Skin Cancer: An Epidemiological, Patient-Centered Update and Review

BACKGROUND

The current vitamin D deficiency epidemic is accompanied by an increase in endemic skin cancer. There are still multiple controversies. This review aims to give practical recommendations regarding vitamin D among people at risk or with a personal history of skin cancer.

METHODS

Narrative review including human research articles published between 2011 and 2021, elaborated bearing in mind an epidemiological, patient-centered approach.

RESULTS

Ultraviolet (UV) exposure (neither artificial nor natural) is not the ideal source to synthesize vitamin D. There is conflicting epidemiological evidence regarding vitamin D, non-melanoma skin cancer (NMSC), and cutaneous melanoma (CMM), confounded by the effect of sun exposure and other factors.

CONCLUSIONS

Current evidence is controversial, and there are no widely applicable strategies. We propose three practical recommendations. Firstly, sun protection recommendations should be kept among people at risk or with a personal history of skin cancer. Secondly, vitamin D should preferably be sourced through diet. In patients with melanoma or at risk of cutaneous cancer, serum vitamin D checks are warranted to detect and avoid its insufficiency.

Vitamin D: Skin, sunshine, and beyond

Vitamin D is a steroid hormone of importance to the field of dermatology. Skin is unique in that it is the site of vitamin D synthesis upon sun exposure and a target organ for its activity. We explore the physiology and metabolic mechanism of action of vitamin D, as well as its effects on the skin. We also discuss the current evidence of the efficacy and safety of oral and topical vitamin D analogues on skin conditions such as psoriasis, atopic dermatitis, vitiligo, sunburn, actinic keratosis, and fibrosing skin disorders. Based on currently available scientific evidence, the National Academy of Medicine's recommended dietary allowance for vitamin D ranges from 400 IU to 800 IU daily based on age categories.

Tanning-Elicited Variations in the Ultraviolet Absorption Spectra of the Cutaneous Tissues: Skin Photobiology and Photomedicine Implications

When ultraviolet radiation is absorbed within the cutaneous tissues, it can trigger a number of phenomena that can have detrimental or beneficial consequences to an individual's health. Tanning is among the most visually noticeable of these phenomena. It may result in significant changes in skin pigmentation and thickness. These spectrally-dependent physiological responses, in turn, can elicit variations in the ultraviolet absorption profiles of the cutaneous tissues and, consequently, alter the occurrence of other ultraviolet-induced photobiological processes such as the breaking of DNA strands and the synthesis of previtamin D3. These tanning-elicited variations in the cutaneous tissues' absorption profiles is often tied to the increased presence of melanin throughout these tissues. However, during the tanning, shifts in the relative content of this pigment within certain skin layers can also be observed. In particular, the stratum basale, the innermost epidermal layer where melanogenesis takes place, can have its relative melanin content significantly reduced in comparison with other epidermal layers. Since the aforementioned photobiological phenomena are preferentially brought about within this layer, such pigmentation shifts may have a more pivotal role in skin photobiology than has been assumed to date. Accordingly, in this work, we investigate the impact of spectrally-dependent tanning-elicited physiological responses, with a particular focus on the inter-layer melanin distribution patterns, on the absorption profiles of the main cutaneous tissues. We also examine how variations in these absorption profiles may alter the outcomes of photo-triggered phenomena associated with the onset of different medical conditions. Our findings are expected to contribute to the advance of the current understanding about skin photobiology, which is indispensable for the success of photomedicine initiatives involving this highly complex organ.

Sunbeds and melanoma risk: time to close the debate

PURPOSE OF REVIEW

In spite of the established scientific evidence on the association of sunbed use with melanoma risk, some have recently expressed scepticism about the carcinogenicity of indoor tanning. This may have raised confusion among both physicians and patients. The purpose of this review is to make the point about the real impact of sunbed use on melanoma risk in light of the most recently published evidence.

RECENT FINDINGS

Seven themes were covered: recent studies on age at first sunbed exposure and melanoma risk; sunbed use and melanoma at different body sites; sunbed use and development of additional primary melanomas; new studies on proportion of melanomas attributable to sunbed use; sunbed use and melanoma risk factors; economic burden of sunbed use; and recent debate over whether indoor tanning contributes to melanoma.

SUMMARY

We were able to apply all epidemiological criteria for causality to the relationship between sunbed use and melanoma. Together with the new evidence on the strength, dose response, and temporality of the association of sunbeds with melanoma, this will hopefully close the debate over whether indoor tanning contributes to melanoma.

Prevalence of Vitamin-D deficiency is related to severity of liver damage in Hepatitis-C patients

Objective

Serum Vitamin-D plays pivotal role in inflammatory and infectious diseases; among them liver infections are more distinct. This study was aimed to determine Vitamin-D status in HCV-infected patients and healthy controls in Faisalabad, Pakistan.

Methods

We performed randomized cross-sectional study of 74 individuals from 20^th August, 2017 to 20^th February 2018 at The University of Faisalabad and Dar us Shifa Clinic, Faisalabad. Fifty-one patients were hepatitis C RNA-PCR positive (22 compensated cirrhotic and 29 decompensated cirrhotic patients). In addition, 23 subjects without liver disease were recruited as healthy control. HCV RNA-PCR was performed by ARTUS ® HCV QS-RGQ V1. Vitamin-D levels were measured by chemiluminescence. SPSS version 20 was used for statistical analysis.

Results

The mean level of Vitamin-D was significantly lower in HCV patients in compensated and decompensated cirrhotic patients (26.85 ng/mL & 20.65 ng/mL respectively) as compared to healthy controls (30.41 ng/mL). This study showed sub optimal level of Vitamin-D in 76.5% of HCV patients. Vitamin-D insufficiency (21-29 ng/mL) as prevalent among healthy individuals (47.8%) as well as in HCV patients (39.2%) (P < 0.001). In addition, Vitamin-D levels showed inverse relationship with more severe conditions of liver disease as 55.2% of decompensated cirrhosis patients were sufferer of Vitamin-D deficiency as compared to 13.6% deficiency of Vitamin-D in compensated cirrhotic group (P <0.0001).

Conclusion

Suboptimal levels of Vitamin-D (deficiency or insufficiency) are prevalent in patients having hepatitis C infection as compared to healthy controls. Deficiency of Vitamin-D was directly associated with severity of disease.

Vitamin D and the skin: what should a dermatologist know?

Although first discovered in 1931, vitamin D has seen an increased interest in the scientific community over the past decades, including the dermatology field. Vitamin D promotes calcium and phosphorus absorption; however, the actions of vitamin D are not confined to bone. Indeed, there is now overwhelming and compelling scientific data that vitamin D plays a crucial role in a plethora of cellular function and in extra-skeletal health. Except for fatty fish livers, very few foods naturally contain vitamin D; and the major source of vitamin D comes from skin exposure to sunlight via ultraviolet B. Keratinocytes are unique in the body as not only do they provide the primary source of vitamin D for the body, but they also possess both the enzymatic machinery to metabolize the vitamin D produced to active metabolites. This has been referred to as the photoendocrine vitamin D system. Vitamin D regulates keratinocytes proliferation and differentiation; and plays a role in the defense against opportunistic infections. Multiple factors are linked to vitamin D status; and a growing number of dermatologic diseases has been linked to vitamin D status such as atopic dermatitis, psoriasis, vitiligo, and cutaneous cancers. In this article, we reviewed the potential determinants of vitamin D status, as its implications in dermatologic diseases.