A recent study reports a reduced risk of ADHD in children whose mothers who took Vitamin D during their pregnancy. This is wonderful news! But note that the mothers were being monitored. Please do not simply supplement vitamin D without having your levels checked. There are risks to bone health in particular if someone is over-supplementing. I monitor serum calcium and Vitamin D25OH, as well as parathyroid hormone and Vitamin D-1,25diOH if indicated.