A new study has found that children of mothers who took Vitamin D while pregnant have fewer symptoms of attention deficit hyperactivity disorder (ADHD) at the age of 2.5.
“For every 10 nmol/L increase in the Vitamin D concentration in umbilical blood, the risk of a being among the 10 percent highest score on the ADHD symptom scale fell by 11 percent,” said Professor Niels Bilenberg of the University of Southern Denmark.
For the study, researchers monitored 1,233 children in the Odense Municipality in Denmark. Vitamin D was measured in the umbilical blood, and mothers completed the Child Behavior Checklist (CBCL) when their child was 2.5 years old. The CBCL questionnaire can be used to identify early symptoms of ADHD, even though an ADHD diagnosis cannot be made at that age, researchers explained.
“The trend was clear: Those mothers who had taken Vitamin D, and had a Vitamin D level (25OHD) in their umbilical blood over 25 nmol/L, had children with lower ADHD scores,” Bilenberg said. “This was after we had corrected for other factors that could explain the link, such as the mother’s age, smoking, alcohol, obesity, education, number of children, psychiatric disease in the parents, child’s sex, age and seasonal variation.”
“We were very surprised that the link was so clear, as there was no previous awareness that this link could be identified at such an early age,” add two of the study’s other authors, medical students Jens Bull Aaby and Mats Mossin.
“It’s impossible to say which children will develop ADHD later on, but it will be interesting to further follow up those children who were at the highest end versus the normal range of the ADHD scale.”
The study offers no explanation as to how Vitamin D can protect against ADHD, but other studies have shown that Vitamin D plays an important role in the early development of the brain, the researchers pointed out.
“We had an idea about it, but we cannot say with certainty that Vitamin D protects against early symptoms of ADHD,” Aaby said. “Our study only indicates that there is a link that we cannot explain in any other way.”
The study was published in The Australia & New Zealand Journal of Psychiatry.
Source: University of Southern Denmark