The vitamin D supply is one of the key factors for the outbreak and the course of influenza epidemics. Norwegian scientists have drawn this conclusion from a study on influenza epidemics, which has now been published in the specialist journal "International Journal of Infectious Diseases". According to this study, with these influenza epidemics the infection and mortality rates increase with decreasing exposure to sunlight and thus, with decreasing vitamin D supply. There are particularly drastic seasonal differences with regard to the proportion of deaths: the number of deaths increases during the "vitamin D winter" up to 20 - 600 fold when the solar radiation is too weak for the vitamin D synthesis via the skin.
"Vitamin D has an antibiotic effect and strengthens the immune system. Stimulated by solar UV radiation, vitamin D is produced via the skin. During the winter months, the vitamin D level decreases as the sun is too low for vitamin D synthesis. Under these circumstances, the "sunshine vitamin" can no longer spread its protective effect to a sufficient extent", explains Professor Johan Moan of the university of Oslo, one of the authors of the study, whilst explaining the context.
In their study, the scientists of the university of Oslo use data on influenza epidemics from Sweden, Norway, the USA, Singapore as well as Japan and compare the infection and mortality rates with the strength of the solar UV radiation on a monthly basis.
Note:
A summary of the study ""Asta Juzeniene, Li-Wei Ma, Mateusz Kwitniewski, Georgy A.Polev, Zoya Lagunova, Arne Dahlback, Johan Moan: The seasonality of pandemic and non-pandemic influenzas: the roles of solar radiation and vitamin D" is available on the SRF website www.sunlightresearchforum.eu to download.
"Vitamin D has an antibiotic effect and strengthens the immune system. Stimulated by solar UV radiation, vitamin D is produced via the skin. During the winter months, the vitamin D level decreases as the sun is too low for vitamin D synthesis. Under these circumstances, the "sunshine vitamin" can no longer spread its protective effect to a sufficient extent", explains Professor Johan Moan of the university of Oslo, one of the authors of the study, whilst explaining the context.
In their study, the scientists of the university of Oslo use data on influenza epidemics from Sweden, Norway, the USA, Singapore as well as Japan and compare the infection and mortality rates with the strength of the solar UV radiation on a monthly basis.
Note:
A summary of the study ""Asta Juzeniene, Li-Wei Ma, Mateusz Kwitniewski, Georgy A.Polev, Zoya Lagunova, Arne Dahlback, Johan Moan: The seasonality of pandemic and non-pandemic influenzas: the roles of solar radiation and vitamin D" is available on the SRF website www.sunlightresearchforum.eu to download.
