Introduction: Diet and dietary interventions have drawn considerable attention in the literature as etiopathogenic factors and therapeutic approaches to Autism Spectrum Disorders (ASD), respectively. The objective of this study was to determine the influence of a gluten-free, casein-free (GFCF) diet on the alterations of behavior in children and adolescents diagnosed with ASD. We also aim to explore the possible association between ASD symptoms and urinary concentrations of beta-casomorphin.

Methods: A total of 28 patients were recruited for this crossover clinical trial. Patients followed a normal diet (including gluten and casein) for three months and a GFCF diet for another three months. The order of the intervention —i.e., beginning with normal diet or with GFCF diet— was determined at random. The subjects were evaluated at three time points: at the onset of the study, after the first diet, and after the second diet. Each evaluation entailed three questionnaires on behavior and autism, a food frequency questionnaire (to determine adherence to the diet) and a determination of concentrations of beta-casomorphin in urine using chromatographic techniques.

Results: No significant behavioral changes were found after a GFCF diet. No association was found between ASD symptoms and urinary concentrations of beta-casomorphin.

Conclusion: A GFCF diet followed for three months do neither show significant changes in behavioral symptoms of autism nor in urine concentrations of beta-casomorphin using chromatographic detection. However, we need further studies including elements of placebo and double-blindness and more sophisticated beta-casomorphin detection techniques to better define subjects who might benefit from these diets.

简介：饮食和饮食干预已分别引起自闭症谱系障碍（ASD）的致病因素和治疗方法，在文献中引起了广泛关注。这项研究的目的是确定无麸质，无酪蛋白（GFCF）饮食对诊断为ASD的儿童和青少年行为改变的影响。我们还旨在探讨ASD症状和尿液中β-酪蛋白吗啡浓度之间的可能联系。

方法：共有28例患者参加了这项交叉临床试验。患者接受正常饮食（包括麸质和酪蛋白）三个月，而GFCF饮食另外三个月。干预的顺序（即从正常饮食开始或从GFCF饮食开始）是随机确定的。在三个时间点对受试者进行评估：在研究开始时，第一次饮食后和第二次饮食后。每次评估都需要三份关于行为和自闭症的调查表，一份食物频率调查表（以确定对饮食的依从性）以及使用色谱技术确定尿液中β-酪蛋白的浓度。

结果：GFCF饮食后未发现明显的行为改变。在ASD症状和尿液中的β-酪蛋白吗啡浓度之间未发现关联。

结论：连续三个月的GFCF饮食使用色谱检测既未显示出自闭症行为症状的显着变化，也未显示尿液中β-酪蛋白的浓度变化。但是，我们需要进一步研究，包括安慰剂和双盲因素以及更复杂的β-casomorphin检测技术，以更好地定义可能从这些饮食中受益的受试者。