Vitamin D status in immigrants in Norway

Author(s): Muhammad M Ahmed, Haakon E Meyer Mette Brekke and Ahmed A Madar

Background: High prevalence of poor vitamin D status has been reported among immigrants in Norway, but there is limited information on vitamin D status among immigrants from the Middle East and sub-Saharan Africa.

Aim: The aim of this study was to describe vitamin D status and potentially associated factors among adults with different regional backgrounds.

Methods: Its cross-sectional study conducted at different immigrant centers in Oslo and adjacent municipalities. Participants: 251 adults (18-50 years) with Middle Eastern, sub-Saharan African and South Asian backgrounds were recruited from January-March 2011. Venous blood samples were collected and serum 25-hydroxyvitamin D (s-25(OH)D) and parathyroid hormone (p-PTH) were analyzed in one batch.

Results: The overall mean s-25(OH)D was 28.9 nmol/l (range 5 to 130 nmol/l). Over 90% had a serum concentration below 50 nmol/L, while around 9% had below 12.5 nmol/l (females 7% and males 2%). Median p-PTH level was within reference values, however, 31% were above the reference value. The mean s-25(OH)D was higher among those with sub-Saharan African backgrounds compared to the other two geographical groups. Sociodemographic factors such as gender and education did not influence s-25(OH)D levels. There was no association between s-25(OH)D levels and diet, sun exposure or clothing habits in males or females.

Conclusion: This study revealed that immigrants with South Asian, Middle Eastern and Sub-Saharan African backgrounds in Oslo have low s-25(OH)D levels. Measures should be taken to ensure adequate vitamin D intake among immigrant groups throughout the year.