A new Finnish study finds that children of women with a vitamin D deficiency during pregnancy are 34 percent more likely to be diagnosed with attention-deficit/hyperactivity disorder (ADHD), compared to those whose mothers had sufficient vitamin D levels in the first and second trimesters.“Alongside genotype, prenatal factors such as vitamin D deficiency during pregnancy can influence the development of ADHD,” said researcher Minna Sucksdorff, M.D., from the University of Turku in Finland.
The study is the first population-level research to show a link between low maternal vitamin D levels in early to mid-pregnancy and an elevated risk for diagnosed ADHD in the children.
The study included 1,067 children born between 1998 and 1999 diagnosed with ADHD in Finland and the same number of matched controls. The data was collected before the current national recommendation in Finland for the intake of vitamin D during pregnancy, which is 10 micrograms per day throughout the year.
Overall, the findings show that the risk for ADHD was 34 percent higher in children whose mother had a vitamin D deficiency during pregnancy. The result was adjusted for maternal age, socioeconomic status and psychiatric history.
Primary investigator Professor Andre Sourander said that, despite the recommendations, vitamin D deficiency is still a major problem. In Finland, for example, mothers’ vitamin D intake among several immigrant groups is not sufficient.
“This research offers strong evidence that a low level of vitamin D during pregnancy is related to attention deficiency in offspring. As ADHD is one of the most common chronic diseases in children, the research results have a great significance for public health,” said Sourander.The study is part of a larger research project whose goal is to discover the associations between the mother’s health during pregnancy and ADHD in offspring. The aim is to develop preventative treatments and measures for identifying children with ADHD risk.
The study was conducted in collaboration between researchers from the University of Turku, Finland, and Columbia University, New York, and was funded by the National Institute of Mental Health in the U.S. and the Academy of Finland. The study is part of the INVEST flagship program of the University of Turku.
