title: Vitamin D and autism: clinical review.
abstract: BACKGROUND
  Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder with multiple genetic and environmental risk factors. The interplay between genetic and environmental factors has become the subject of intensified research in the last several years. Vitamin D deficiency has recently been proposed as a possible environmental risk factor for ASD.
  
  
  OBJECTIVE
  The aim of the current paper is to systematically review the research regarding the possible connection between ASD and vitamin D, and to provide a narrative review of the literature regarding the role of vitamin D in various biological processes in order to generate hypotheses for future research.
  
  
  RESULTS
  Systematic data obtained by different research groups provide some, albeit very limited, support for the possible role of vitamin D deficiency in the pathogenesis of ASD. There are two main areas of involvement of vitamin D in the human body that could potentially have direct impact on the development of ASD: (1) the brain (its homeostasis, immune system and neurodevelopment) and (2) gene regulation.
  
  
  CONCLUSIONS
  Vitamin D deficiency--either during pregnancy or early childhood--may be an environmental trigger for ASD in individuals genetically predisposed for the broad phenotype of autism. On the basis of the results of the present review, we argue for the recognition of this possibly important role of vitamin D in ASD, and for urgent research in the field.
authors.affiliation: Institute of Health and Wellbeing, University of Glasgow, Caledonia House, Dalnair Street, RHSC, Yorkhill, Glasgow G3 8SJ, UK. eva.kocovska@glasgow.ac.uk
authors.forename: Eva
authors.initials: E
authors.lastname: Kočovská
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Fernell
authors.forename: Eva
authors.initials: E
authors.lastname: Billstedt
authors.forename: Helen
authors.initials: H
authors.lastname: Minnis
authors.forename: Christopher
authors.initials: C
authors.lastname: Gillberg
mesh_terms: D001321:Autistic Disorder / Q000453:epidemiology*; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000453:epidemiology*; D005260:Female; D006801:Humans; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology*; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology*; D012307:Risk Factors; D014808:Vitamin D Deficiency / Q000453:epidemiology*