Researchers have shown that dietary supplements are not good for children with Autism Spectrum Disorder (ASD) as it may result in both insufficient and excessive nutrients.
As such children are picky eaters, sometimes parents of children with ASD try nutritional supplements and dietary regimens such as gluten-free and casein-free (GFCF) diets without professional supervision.
"Many families try a GFCF diet in an attempt to improve symptoms of ASD," said lead investigator Patricia A. Stewart, assistant professor of paediatrics at the University of Rochester's Medical Center.
For the study, 368 autistic children between 2 and 11 years of age were recruited and three-day food records were completed for the children by their care-givers.
The children were consuming similar amounts of micro-nutrients as children without ASD.
Although ASD children are given supplements more often - 56 percent vs. 31-37 percent of the general population -- even after supplementation, 40-55 percent were lacking in calcium and 30-40 percent were lacking in vitamin D.
"In clinical practice, each patient needs to be individually assessed for potential nutritional deficiencies or excess. When supplements are used, careful attention should be given to adequacy of vitamin D and calcium intake," Stewart added.
The study appeared in the Journal of the Academy of Nutrition and Dietetics.