Summary of Findings
This paper presents a detailed systematic review and meta-analysis involving twenty separate research studies, aiming to determine whether there is a heightened occurrence of obesity among children diagnosed with Autism Spectrum Disorder (ASD). The core objective is to explore two key relationships: first, whether children on the autism spectrum are more likely to be obese, and second, whether children affected by obesity show a higher incidence of ASD.
Background and Purpose
Roughly 20% of children face challenges related to excessive weight. Among these, children with developmental disorders like ASD seem particularly vulnerable. This increased susceptibility can be partly attributed to their distinct eating habits—many prefer foods high in calories and often consume fewer fruits and vegetables. Moreover, certain medications prescribed to manage behavioral symptoms in ASD, such as atypical antipsychotics, may contribute to weight gain.
To investigate the obesity-ASD connection, researchers conducted thorough searches of academic databases—namely PubMed, Scopus, and PsychINFO—in May 2021. They selected twenty studies that fit stringent criteria, such as including participants under 18 and having control groups for comparison. Studies lacking these controls were not considered.
Key Findings
The analysis revealed that 17% of children with ASD were classified as obese, with a confidence interval ranging from 13% to 22%. Furthermore, these children exhibited a 58% increased likelihood of becoming obese compared to their peers without ASD. The data also indicated an age-related trend: adolescents between 13 and 17 years old showed higher obesity rates than younger children. These patterns align with previous meta-analytical findings in the field.
Of the twenty studies examined, seventeen originated from the United States, while the remaining three were conducted in Europe—specifically in Ireland, the Netherlands, and Spain. Interestingly, none of the European studies reported a statistically meaningful difference in obesity rates between ASD and non-ASD groups. However, this result may be influenced by limitations in those studies, such as small sample sizes or control groups that included children with other psychiatric conditions, which themselves can be linked to increased obesity risk. Prior reviews have suggested that the association between ASD and weight issues is more pronounced in American populations, highlighting a need for larger-scale research within European settings to draw firmer conclusions.
Study Limitations and Data Considerations
One notable limitation mentioned by the authors concerns the source of anthropometric data in eleven studies—it was collected through parental reports rather than clinical measurements. To examine the potential impact of this, the researchers performed a secondary analysis that segmented studies based on how weight and height data were obtained. The results showed no significant variations between the groups, suggesting the method of measurement did not substantially alter the findings.
Gaps in Research
In addition to assessing obesity rates among children with ASD, the study also aimed to determine whether obesity in children correlated with higher rates of autism diagnoses. Unfortunately, the researchers were unable to analyze this aspect due to a lack of eligible studies featuring appropriate control groups. This gap in the literature presents a clear opportunity for future research to explore this inverse relationship in a structured and controlled manner.