Diet and vitamin D status among pregnant Pakistani women in Oslo

In the present study the diet and the nutritional status of pregnant Pakistani immigrant women have been compared with a group of Norwegian women.

A cross-sectional survey of women in the 18th week of pregnancy.

Women referred to routine ultrasound examination at Aker and Ullevål Hospitals in Norway.

All (58) healthy women of Pakistani origin referred from October of 1991 to January of 1992 were included, of whom 38 (66%) participated. Forty-five Norwegian women were randomly included in the same period and 38 (84%) of these women participated.

The serum levels of 25-hydroxyvitamin D3 were significantly lower in the Pakistanis compared with the Norwegians (median 19 nmol/l vs 55 nmol/l, P < 0.001) and 83% of the Pakistani women had 25-hydroxyvitamin D3 levels below the reference value (< 30 nmol/l). The Pakistanis had higher levels of serum parathyroid hormone (median 2.6 vs 1.6 pmol/l, P < 0.001). The Pakistanis also had a lower dietary intake of vitamin D than that of the Norwegians (median 2.2 vs 3.3 micrograms/day, P < 0.05), and a lower total intake, including supplements (median 2.9 vs 7.0 micrograms/day, P < 0.001). Among the Pakistanis a correlation was found between the dietary intake of margarine, the main source of vitamin D in the diet, and the concentration of 25-hydroxyvitamin D3 in serum, r = 0.48 (P = 0.01). In general, the Pakistanis avoided any direct sunshine exposure, and no relation between outdoor activity and serum level of 25-hydroxyvitamin D3 was found. The Pakistani women had a lower intake of calcium than the Norwegians (median 793 vs 1134 mg/day, P < 0.001).

This study has shown that Pakistani women living in Oslo are at great risk of developing vitamin D deficiency during pregnancy. The main reasons for this are avoidance of sun exposure, a low dietary intake of vitamin D, and no or little use of supplementation.