Sweden’s vitamin D fortification program offsets deficiencies for majority of infants, study finds

New research supports the successful implementation of Sweden’s expansion of its mandatory vitamin D fortification in 2018. Involving 1,800 infants in Sweden, the majority of young children screened had good vitamin D status, while none had indications of deficiency. At the same time, intake of the essential nutrient was too low for some. 

This study assessed vitamin D status among young children following the 2018 expansion, while identifying main vitamin D sources and their climate impact.

“We have enjoyed an excellent collaboration with the Swedish Food Agency, and our results show the crucial importance of fortified dairy products for vitamin D intake among young children in Sweden, especially after they stop taking vitamin D drops,” says co-author André Hesselink, dietician and doctoral student in clinical nutrition at the University of Gothenburg, Sweden.

“In addition, the expansion of the mandatory fortification program provides an opportunity for plant-based alternatives to play a more prominent role in the future for ensuring adequate intake of vitamin D and reducing the climate impact of our dietary habits.”

Because it can be difficult to get enough vitamin D during early development, health guidelines — such as those in Sweden — recommend daily supplemental Vitamin D drops for children from birth up to two years of age.

The study notes that milk (≤ 1.5% fat), margarine, and other fat spreads have been fortified with vitamin D since 2007. The 2018 expansion aimed to address the country’s poor vitamin D status by increasing fortification levels and the number of products required to be fortified, for example, to include all milk and yogurt (≤ 3% fat), plant-based milk, and yogurt alternatives.

Moreover, most porridge and a popular cereal drink intended for young children are also fortified with vitamin D.

No vitamin D deficiencies

Published in the Nutrition Journal, the study was carried out by the University of Gothenburg, the Swedish Food Agency, and Research Institutes of Sweden.

The initiative involved 1,074 children aged 18 months and 746 at the age of four, whose data were obtained from the survey “Riksmaten småbarn,” which took place between 2021 and 2024.

The results reveal that 16% of the 18-month-olds and 61% of the four-year-olds were below the average required vitamin D intake of 7.5 mcg per day through diet and vitamin D drops.

However, none of the children were vitamin D deficient, and most of them had sufficient levels, including 93% in the younger age group and 96% in the older age group.

Climate-impacting foods

In addition, the study assessed the climate impact of the most commonly consumed fortified foods in Sweden that provide children with vitamin D.

The most important sources for 18-month-olds were vitamin D drops and fortified dairy products, porridge, and cereals. For the four-year-olds, it was fortified dairy products and fat spreads.

The researchers found that animal-based foods, which are common sources of vitamin D for children, also contributed more to greenhouse gas emissions compared to plant-based alternatives.

While the study noted that dairy products contribute significantly to diet-related greenhouse gas emissions, fortified spreads and fortified plant-based alternatives offered the highest vitamin D content with the lowest environmental impact.

The authors say this affirms plant-based alternatives as a “climate-friendly” source of vitamin D.

Earlier this year, scientists found that high-dose vitamin D3 supplementation during pregnancy is positively associated with visual and verbal memory, as well as flexibility among children by the age of 10.