Vitamin D is essential- it plays a critical role in everything from bone strength and growth, to immune system function and cardiovascular health. Until recently, the merits of Vitamin D were poorly recognized and at least in pediatrics, levels were infrequently checked. Now, when I am drawing labs for concerns of hyperlipidemia or short stature, chronic fatigue, anxiety or almost anything really, I add a Vitamin D level – because without fail, the levels are always low. It seems counterintuitive, that in our mild climate with sunny skies that anyone would have sub-therapeutic levels, but since vitamin D is relatively sparse in our edible diet and skin synthesis of the vitamin requires ultraviolet light – it is the norm to see serum concentrations below 30.

I came across an interesting case report yesterday at work that was published in the journal Pediatrics (Volume 135, number 1, January 2015) that noted that lower concentrations of Vitamin D may lead to increasing brain size, altered brain shape and enlarged ventricles – all features observed in children diagnosed with an Autism Spectrum Disorder (ASD). Additionally, the article noted that higher concentrations of the active form of Vitamin D (once converted in the liver) is associated with reduced risk of an ASD, and concurrently, low levels may cause ASD symptoms.