The potential impact of the extended vitamin D fortification policy during pregnancy varies by continent of origin - a population-representative Swedish cohort.

Purpose: We aimed to explore the potential impact of Sweden's extended fortification policy, launched in 2018, on vitamin D intake during pregnancy, depending on continent of origin.

Methods: The population-representative GraviD cohort was conducted within the antenatal care in 2013-2014 in Southwestern Sweden. Background data including country of origin were collected through questionnaires. In the third trimester, participants (N = 1761) answered a vitamin D questionnaire which included intakes of margarine, milk, and fermented milk. Reported vitamin D intake in 2013-2014 was compared to simulated vitamin D intake following the 2018 vitamin D fortification policy expansion.

Results: Pre-expansion reported median intake of vitamin D from fortified foods differed by continent of origin (p < 0.001). Pre-expansion intake was highest among participants from Northern Europe (2.4 µg/day) compared to those from Continental Europe (2.0 µg/day, p = 0.002), Asia (1.6 µg/day, p < 0.001), and Africa (2.0 µg/day, p = 0.001). Post-expansion simulated median vitamin D intake from fortified foods was higher among participants from Northern Europe (6.3 µg/day) compared to Asia (5.0 µg/day, p < 0.001) and Africa (5.0 µg/day, p = 0.013). Participants from Continental Europe had the largest change (3.6 µg/day) between pre- and post-expansion, while those born in Asia had the smallest change (2.9 µg/day).

Conclusion: The Swedish fortification policy expansion had a positive potential impact on vitamin D intake during pregnancy, but the effect depended on the continent of origin. The potential impact was smallest for participants from Asia and Africa, indicating that the current Swedish fortification policy is most beneficial for individuals of European origin.