The Quantitative Assessment of Solar UV [ultraviolet] Exposure for Vitamin D Synthesis in Australian Adults (AusD) Study aimed to better define the relationship between sun exposure and serum 25-hydroxyvitamin D (25(OH)D) concentration. Cross-sectional data were collected between May 2009 and December 2010 from 1,002 participants aged 18-75 years in 4 Australian sites spanning 24° of latitude. ...

OBJECTIVES Seasonal variations in ultraviolet B (UVB) radiation cause seasonal variations in vitamin D status. This may influence immune responses and play a role in the seasonality of influenza. METHODS Pandemic and non-pandemic influenzas in Sweden, Norway, the USA, Singapore, and Japan were studied. Weekly/monthly influenza incidence and death rates were evaluated in view of monthly UVB fl...

There is an ongoing debate how to balance between beneficial and adverse effects of UV-exposure. On the one hand, solar UV-radiation represents the most important environmental risk factor for the development of non-melanoma skin cancer. Therefore, sun protection is a key principle to prevent these malignancies, especially in risk groups. On the other hand, artificial or solar UV-radiation is r...

The synthesis of vitamin D in skin is a two-stage process that begins with the production of previtamin D after irradiation of 7-dehydrocholesterol by ultraviolet (UV) radiation. A number of personal and environmental factors control the probability of a suitable UV photon reaching a molecule of 7-dehydrocholesterol in the skin. These are astronomical factors that govern the solar zenith angle ...

Ultraviolet (UV) radiation has both beneficial and harmful effects on the human body. Its most important beneficial effect may be vitamin D production in the skin, also known as vitamin D photosynthesis. This is of particular interest for the elderly who often show vitamin D-deficiency. Intentional UV exposure has been recommended by different institutions in order to increase vitamin D levels....

In humans, the main source of vitamin D comes from photoconversion of 7-dehydrocholesterol in the skin to cholecalciferol (vitamin D3) by solar ultraviolet radiation (UVB: 290-320 nm). Vitamin D formed in the skin or the small amount absorbed from the diet is hydroxylated at the 25 position to produce 25 hydroxyvitamin D (25OHD), which is considered to be a reliable index of an individual’s vit...

Introduction: Ultraviolet index (UVI) is a dimensionless scale, which describes the maximum intensity and biologic effects of UV during a specific time, on surface of the earth. The UVI is  an  international  standard measurement of  the  strength  of sunburn  producing ultraviolet radiation at a particular place and time. This index is an easy and understandable concept for pr...

Solar ultraviolet (UV) radiation is one of the most important factors in the development of skin cancer in human, solar erythema and skin aging. Nevertheless, numerous studies have shown the benefits of UV solar radiation in moderate doses, such as the reduction of blood pressure and mental health, treatment of various diseases, and the synthesis of vitamin D in the skin. This paper analyses da...

introduction: ultraviolet (uv) radiation affects human organs such as skin, eyes and immune system, as well as animals and plants. the main natural source of uv radiation is the sun. to study the effects of solar uv radiation there is a need to quantify variations of solar energy received on the earth surface at different intervals. materials and methods: to measure uv radiation a broadband fib...

The ultraviolet radiation present in sunlight is immune suppressive. Recently we showed that solar-simulated ultraviolet radiation (ultraviolet A + B; 295-400 nm), applied after immunization, suppressed immunologic memory and the elicitation of delayed-type hypersensitivity to the common opportunistic pathogen, Candida albicans. Further, we found that wavelengths in the ultraviolet A region of ...