Why are children with autism at higher risk for obesity?

by Rebecca Israel, MS and Charles Li, MD

June 04, 2020

  • Children with autism are nearly twice as likely to be obese than with typical developing children.

  • Children with autism report less time exercising than typical developing children.

  • Children with autism report slightly more time watching television than typically developing children, but relatively the same overall screen time per day.

In 2017, researchers reviewed fifteen studies involving millions of participants with and without autism spectrum disorder (ASD). They found that the odds of being obese were higher in those with ASD compared to the total sample and there was little difference in the odds of being overweight.

Source: Association among obesity, overweight and autism spectrum disorder: a systematic review and meta-analysis

This statistic is noteworthy and an important public health issue. In this article, we explored possible explanations for the differences in obesity rates among children.

Top Questions and Answers

Study design

Researchers took a sample of 13-years-old boys from a large survey in Ireland. They asked questions about physical activity, sports participation, screen time, and weight.

They formed two study groups: autism and typically developing boys. The typically developing group was considered a good representation of the Irish population.

Source: Physical Activity, Screen-Time Behavior, and Obesity Among 13-Year Olds in Ireland With and Without Autism Spectrum Disorder

Of the boys with ASD, 22 (34.9 %) were overweight or obese, compared to 18 children (24.7 %) in the TD group. Overweight or obese status was more prevalent among the group with ASD.

Physical Activity

An established method of maintaining a healthy weight is regular physical activity. In Ireland, the porportation of school-age children who meet daily exercise guidelines by health experts is higher than in other countries, including the United States.

For children with ASD, research has identified a number of additional benefits to being physically active, such as improvements in social skills, sleep quality, and feelings of enjoyment.

Participants were asked how many days they engaged in moderate to hard exercise for at least 20 minutes over a two week period. The autism group most commonly exercised 1-2 days, while the typically developing group most commonly exercised 9 or more days.

Research findings point to several reasons for why youth with ASD refrain from physical activity, such as limitations in social-communication, lack of motor domain skills, and social exclusion from activities.

Screen Time

In a world of endless technology, children may have access to more devices than they know what to do with. Basically, the more time spent in front of a screen, the less time partaking in physical activities.

In the study results, children with and without autism spent a similar amount of time in front of a screen each day. However, children with autism reported watching television for longer.

Research into media-related behaviors suggests that children with autism are more likely to engage in nonsocial media such as television. Watching television may be appealing to children with autism because it does not require social integration skills.

Source: Prevalence and Correlates of Screen-Based Media Use Among Youths With Autism Spectrum Disorders

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