Symptomatic Vitamin and Nutrient Deficiencies of Autism Spectrum Disorder and the Potential for Treatment

Autism spectrum disorder (ASD) is a heterogeneous neurobehavioral disorder. Children with ASD often have restrictive diets that can be due to food aversion, sensory sensitivities, ritualistic behavior, or comorbid gastrointestinal issues. Diet and nutritional status play a critical role in the health of neurodevelopment, and the microbiome, and can affect cognition, motor and sensory status, behavior, and sleep. Children with ASD are 5 times more likely to develop eating problems and secondary vitamin and nutritional deficiencies. Such dietary restriction has been causative of vitamin and nutritional deficiencies that can lead to permanent sequelae if not adequately identified and treated. Symptoms of these deficiencies can be subtle and misleading and, thus, underrecognized. This review discusses various symptomatic vitamin and nutrient deficiencies associated with dietary restrictions that can occur in children and adolescents with ASD of which clinicians need to be aware. With treatment, symptoms can be reversible. Without timely treatment, sequelae can be permanent.