Core Symptoms of Autism Improved After Vitamin D Supplementation

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder caused by a complex interaction between genetic and environmental risk factors. Among the environmental factors, vitamin D-3 (cholecaliferol) seems to play a significant role in the etiology of ASD because this vitamin is important for brain development. Lower concentrations of vitamin D-3 may lead to increased brain size, altered brain shape, and enlarged ventricles, which have been observed in patients with ASD. Vitamin D-3 is converted into 25-hydroxyvitamin D-3 in the liver. Higher serum concentrations of this steroid may reduce the risk of autism. Importantly, children with ASD are at an increased risk of vitamin D deficiency, possibly due to environmental factors. It has also been suggested that vitamin D-3 deficiency may cause ASD symptoms. Here, we report on a 32-month-old boy with ASD and vitamin D-3 deficiency. His core symptoms of autism improved significantly after vitamin D-3 supplementation. This case suggests that vitamin D-3 may play an important role in the etiology of ASD, stressing the importance of clinical assessment of vitamin D-3 deficiency and the need for vitamin D-3 supplementation in case of deficiency.