Dietary intake and gastrointestinal symptoms are altered in children with Autism Spectrum Disorder: the relative contribution of autism-linked traits.

This study looked at eating habits and stomach problems in 121 children with autism compared to children without autism. Children with autism ate fewer fruits and vegetables, had less variety in their diet, and experienced more constipation and stomach issues. The researchers found that certain autism behaviors affected what children ate, but stomach problems were mainly caused by poor diet quality rather than autism behaviors directly. This suggests that improving diet quality could help reduce stomach problems in children with autism.

This cross-sectional study compared dietary intake and gastrointestinal symptoms between 121 children with ASD and 121 typically developing children, then examined how autism-linked traits contribute to these issues within the ASD group. Children with ASD showed significantly poorer diets with reduced vegetable/fruit consumption, less food variety, more inadequate/unbalanced dietary intake, and increased constipation/GI symptoms. Within the ASD group, specific autism traits differentially contributed to dietary problems: compulsive behavior and taste/smell sensitivity affected vegetable/fruit intake, self-injurious behavior reduced food variety, and ASD symptom severity plus limited variety eating behaviors primarily contributed to inadequate/unbalanced diets. Importantly, unbalanced dietary intake was independently associated with GI symptoms, while autism traits showed no direct contribution to GI problems, suggesting diet quality mediates the relationship between autism traits and gastrointestinal issues.

Findings suggest targeting ASD symptom severity and expanding dietary variety could improve nutritional status. Since unbalanced diet independently predicted GI symptoms, nutritional interventions may be more effective than focusing solely on autism behaviors for managing gastrointestinal issues. Early identification of dietary problems and comprehensive nutritional support should be prioritized in ASD care.

Single cross-sectional study design prevents causal inferences. Sample characteristics not fully described. Study type not specified. Unclear if dietary assessment methods were validated. Limited generalizability without demographic details of participants.

Dietary and gastrointestinal (GI) problems have been frequently reported in autism spectrum disorder (ASD). However, the relative contributions of autism-linked traits to dietary and GI problems in children with ASD are poorly understood. This study firstly compared the dietary intake and GI symptoms between children with ASD and typically developing children (TDC), and then quantified the relative contributions of autism-linked traits to dietary intake, and relative contributions of autism-linked traits and dietary intake to GI symptoms within the ASD group. A sample of 121 children with ASD and 121 age-matched TDC were eligible for this study.

The dietary intake indicators included food groups intakes, food variety, and diet quality. The autism-linked traits included ASD symptom severity, restricted repetitive behaviors (RRBs), sensory profiles, mealtime behaviors, and their subtypes. Linear mixed-effects models and mixed-effects logistic regression models were used to estimate the relative contributions. Children with ASD had poorer diets with fewer vegetables/fruits, less variety of food, a higher degree of inadequate/unbalanced dietary intake, and more severe constipation/total GI symptoms than age-matched TDC.

Within the ASD group, compulsive behavior (a subtype of RRBs) and taste/smell sensitivity were the only traits associated with lower vegetables and fruit consumption, respectively. Self-injurious behavior (a subtype of RRBs) was the only contributing trait to less variety of food. Limited variety (a subtype of mealtime behavior problems) and ASD symptom severity were the primary and secondary contributors to inadequate dietary intake, respectively. ASD symptom severity and limited variety were the primary and secondary contributors to unbalanced dietary intake, respectively.

Notably, unbalanced dietary intake was a significant independent factor associated with constipation/total GI symptoms, and autism-linked traits manifested no contributions. ASD symptom severity and unbalanced diets were the most important contributors to unbalanced dietary intake and GI symptoms, respectively. Our findings highlight that ASD symptom severity and unbalanced diets could provide the largest benefits for the dietary and GI problems of ASD if they were targeted for early detection and optimal treatment.