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Serum 25(OH)D concentrations in sunny Israel
W Saliba1, H S Rennert, A Kershenbaum
1Department of Community Medicine and Epidemiology, Carmel Medical Center, Clalit Health Services, and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, 7 Michal St., Haifa 34362, Israel. saliba_wa@clalit.org.il
Summary:
This study assesses vitamin D status in Israel. Serum 25(OH)D levels <25 and <50 nmol/L are common in Israel with noted differences between Arabs and Jews, Arab females were particularly at high risk. These findings may require public health intervention at the population level.
Introduction:
Small studies from Israel have suggested a high prevalence of hypovitaminosis D. The objective of this study was to evaluate the extent of hypovitaminosis D among demographic subgroups in Israel.
Methods:
The data of this study are from the Clalit Health Services (CHS) which is a non-for-profit health maintenance organization (HMO) covering more than half of the Israeli population. We included all CHS members for whom a 25(OH)D test result in 2009 was available and who were not taking vitamin D supplements in 2008-2009 before that 25(OH)D result. Complete data were available for 198,834 members.
Results:
The mean level of 25(OH)D was 51.9 ± 24.5 nmol/L and was higher in summer compared to winter (P < 0.0001). Level <25, <37.5, and <50 nmol/L were detected in 14.4%, 30.7%, and 49.9% of tests; 16.4% had levels >75 nmol/L. Females had higher prevalence of 25(OH)D levels < 50 nmol/L which were found in 51.8% of females versus 45.0% in males (P < 0.0001); 76.7% of the Arabs had levels <50 nmol/L versus 46.5% in Jews (P < 0.0001). Arabs females were particularly at high risk for 25(OH)D <50 nmol/L; 84.8% of them had levels <50 nmol/L versus 48.1% of Jewish females (P < 0.0001). The relation of 25(OH)D levels with age had a sinusoidal shape among Jews, a U-shape in Arab females, and inverse linear pattern in Arab males.
Conclusions:
25(OH)D levels <25 and <50 nmol/L are common in Israel. Public health measures are needed for values lesser than about 30 nmol/L and further monitoring of concentrations between about 30 and 50 nmol/L to determine if there are adverse health effects.
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