Food & Beverages

Biography

Biography: Klaus W. Lange

Abstract

Autism is a complex psychiatric disorder characterized by impairments in social interaction, restricted patterns of behavior and impairments in communication. In the framework of the “opioid excess theory”, these symptoms have been likened to the behavioral effects of opiates. A possible dietary basis of autism has been proposed, hypothesizing that certain food proteins such as gluten and casein can be transformed to opioid peptides during digestion. These peptides might eventually be able to enter the blood stream and act upon the central nervous system. As a consequence, a diet low in such proteins has been hypothesized to ameliorate the behavioral symptoms of children with autism. More than 80 % of parents of children with autism spectrum disorder reported some kind of dietary intervention for their child (gluten-free and casein-free (GFCF) diet in 29 %). The majority of studies evaluating GFCF diet outcomes failed to meet basic methodological standards of interventional science. Comparison of study results did not show any clear-cut results, with a substantial proportion of studies failing to show any positive dietary effect. The results of more sophisticated trials were far from equivocal and the studies differed in many methodological aspects. Some variables such as information source and trial duration seemed to affect outcome. Evidence of the effectiveness of the GFCF diet in the treatment of autism is sparse. Rigorous scientific evaluations partly failed to confirm therapeutic effects of the GFCF diet. These and other negative results related to the opioid excess theory weaken the underlying rationale for GFCF diet use. Nevertheless, more sophisticated investigations should be conducted in order to identify possible benefits and harms of such a dietary approach. At present a gluten-free and casein-free diet should only be administered if an allergy or intolerance to nutritional gluten or casein is diagnosed.