Serum 25(OH)D concentrations in sunny Israel

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.