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There is an agreement among all professionals that autism is one of the most puzzling diseases. It is a complex neuro developmental disorder, the prevalence of which has surged in the last 2 decades Such apparent increase in the prevalence of autism corresponds with the increasing medical advice to avoid the sun, an advice that has probably lowered vitamin D level. Many studies reported low serum concentrations of 25 hydroxy vitamin D in autistics but there were a few reports about autistic manifestations in vitamin D deficiency rickets. This is a commentary about a study that reported a prevalence of 25.71% of mild to moderate autism in a group of Egyptian children with vitamin D deficient or insufficient rickets compared to none of age and sex matched healthy controls and showed a significant negative correlation between the severity of autistic manifestations and serum level of 25 hydroxy vitamin D.