Full Papers

Dietary Survey and Nutritional Epidemiology

Vitamin D status among immigrant mothers from Pakistan, Turkey and Somalia and their infants attending child health clinics in Norway

Ahmed A. Madar^a1 c1, Lars C. Stene^a2 and Haakon E. Meyer^a1a2

^a1 Institute of General Practice and Community Medicine, University of Oslo, PO Box 1130, Blindern, N-0318 Oslo, Norway

^a2 Division of Epidemiology, Norwegian Institute of Public Health, Oslo, Norway

Abstract

High prevalences of vitamin D deficiency have been reported in non-Western immigrants moving to Western countries, including Norway, but there is limited information on vitamin D status in infants born to immigrant mothers. We aimed to describe the vitamin D status and potentially correlated factors among infants aged 6 weeks and their mothers with Pakistani, Turkish or Somali background attending child health clinics in Norway. Eighty-six healthy infants and their mothers with immigrant background were recruited at the routine 6-week check-up at nine centres between 2004 and 2006. Venous or capillary blood was collected at the clinics from the mother and infant, and serum separated for analysis of 25-hydroxyvitamin D (s-25(OH)D) and intact parathyroid hormone (s-iPTH). The mean maternal s-25(OH)D was 25·8 nmol/l, with 57 % below 25 nmol/l and 15 % below 12·5 nmol/l. Of the mothers, 26 % had s-iPTH>5·7 pmol/l. For infants, mean s-25(OH)D was 41·7 nmol/l, with 47 % below 25 nmol/l and 34 % below 12·5 nmol/l. s-25(OH)D was considerably lower in the thirty-one exclusively breast-fed infants (mean 11·1 nmol/l; P < 0·0001). Use of vitamin D supplements and education showed a positive association with maternal s-25(OH)D. There was no significant association between mother's and child's s-25(OH)D, and no significant ethnic or seasonal variation in s-25(OH)D for mothers or infants. In conclusion, there is widespread vitamin D deficiency in immigrant mothers and their infants living in Norway. Exclusively breast-fed infants who did not receive vitamin D supplements had particularly severe vitamin D deficiency.

(Received January 08 2008)

(Revised July 14 2008)

(Accepted July 14 2008)

(Online publication September 09 2008)

Key Words:

• Vitamin D;
• Maternal nutrition;
• Infant nutrition

Correspondence:

^c1 Corresponding author: Dr Ahmed A. Madar, fax +47 22 85 05 90, email a.a.madar@medisin.uio.no

Footnotes

Abbreviations: s-iPTH, serum intact parathyroid hormone; s-25(OH)D, serum 25-hydroxyvitamin D