The high prevalence of vitamin D insufficiency across Australian populations is only partly explained by season and latitude


Autoria(s): van der Mei, Ingrid A. F.; Ponsonby, Anne-Louise; Engelsen, Ola; Pasco, Julie A.; McGrath, John J.; Eyles, Daryl W.; Blizzard, Leigh; Dwyer, Terence; Lucas, Robyn; Jones, Graeme
Data(s)

01/08/2007

Resumo

<b>Background</b> Inadequate sun exposure and dietary vitamin D intake can result in vitamin D insufficiency. However, limited data are available on actual vitamin D status and predictors in healthy individuals in different regions and by season.<br /><b><br />Methods</b> We compared vitamin D status [25-hydroxyvitamin D; 25(OH)D] in people < 60 years of age using data from cross-sectional studies of three regions across Australia: southeast Queensland (27°S; 167 females and 211 males), Geelong region (38°S; 561 females), and Tasmania (43°S; 432 females and 298 males).<br /><b><br />Results</b> The prevalence of vitamin D insufficiency (≤ 50 nmol/L) in women in winter/spring was 40.5% in southeast Queensland, 37.4% in the Geelong region, and 67.3% in Tasmania. Season, simulated maximum daily duration of vitamin D synthesis, and vitamin D effective daily dose each explained around 14% of the variation in 25(OH)D. Although latitude explained only 3.9% of the variation, a decrease in average 25(OH)D of 1.0 (95% confidence interval, 0.7–1.3) nmol/L for every degree increase in latitude may be clinically relevant. In some months, we found a high insufficiency or even deficiency when sun exposure protection would be recommended on the basis of the simulated ultraviolet index.<br /><br /><b>Conclusion</b> Vitamin D insufficiency is common over a wide latitude range in Australia. Season appears to be more important than latitude, but both accounted for less than one-fifth of the variation in serum 25(OH)D levels, highlighting the importance of behavioral factors. Current sun exposure guidelines do not seem to fully prevent vitamin D insufficiency, and consideration should be given to their modification or to pursuing other means to achieve vitamin D adequacy.<br />

Identificador

http://hdl.handle.net/10536/DRO/DU:30042839

Idioma(s)

eng

Publicador

U.S. Department of Health and Human Services, National Institute of Environmental Health Sciences

Relação

http://dro.deakin.edu.au/eserv/DU:30042839/pasco-highprevalence-2007.pdf

http://dx.crossref.org/10.1289/ehp.9937

Direitos

2007, National Institute of Environmental Health Sciences

Palavras-Chave #25(OH)D #behavior #latitude #UV index #UVR #vitamin D #vitamin D index
Tipo

Journal Article