Understanding the causes of obesity in children with trisomy 21: hyperphagia vs physical inactivity.
Kids with Down syndrome show clear food preoccupation and low activity—target both, not just exercise, to prevent obesity.
01Research in Context
What this study did
Researchers compared kids with Down syndrome to kids with Prader-Willi syndrome and kids with lifestyle obesity. They used surveys and activity trackers to measure food preoccupation and daily movement.
The goal was to see if Down syndrome obesity comes from eating too much or moving too little.
What they found
Kids with Down syndrome scored in the middle on food preoccupation. They were less obsessed with food than Prader-Willi kids but more than typical obese kids.
They also moved less than all other groups. Both habits may feed their extra weight.
How this fits with other research
Bertapelli et al. (2016) already showed that exercise-only plans fail for Down syndrome youth. Allen et al. (2016) now tells us why: low activity is only half the story; food focus matters too.
McQuaid et al. (2024) seems to disagree. In adults with Down syndrome, extra weight did not raise diabetes or blood pressure like it does in typical adults. The gap is age. Kids build fat through behavior; adults may carry safer fat.
Esparza Ocampo et al. (2025) adds another layer. Even normal-weight Down syndrome kids already show poor lipid profiles. This means metabolic risk starts early, before obesity looks obvious.
Why it matters
When you write a behavior plan for a child with Down syndrome, screen both food seeking and daily steps. Pair mealtime interventions with fun, vigorous movement breaks. Do not wait for weight gain to act; lipid and activity checks should start young.
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02At a glance
03Original abstract
BACKGROUND: Individuals with intellectual disabilities are at increased risk of becoming overweight or obese. This is particularly evident in people with trisomy 21 and Prader-Willi syndrome (PWS). Although metabolic factors are known to contribute to obesity in trisomy 21 and hyperphagia plays a primary role in PWS, hyperphagia has not yet been investigated as a possible contributing factor to obesity in trisomy 21. METHODS: Participants comprised three diagnostic groups: trisomy 21 (T21 group), PWS (PWS group) and lifestyle-related obesity (LRO group). They were required to be aged 6-18 years and have a body mass index over the 85th percentile for age and gender. A parent of each participant completed the Hyperphagia Questionnaire and the Children's Leisure Activity Study Survey. Mean scores for each domain and across all domains of the Hyperphagia Questionnaire and the Children's Leisure Activity Study Survey were compared between diagnostic groups using linear regression analysis. RESULTS: The study group consisted of 52 young people (23 men and 29 women) aged 6-18 years (mean 12.5 years; T21 group n = 17, PWS group n = 16 and LRO group n = 19). As hypothesised, the PWS group had the highest mean scores across all domains of the Hyperphagia Questionnaire, and the LRO group had the lowest. Food-seeking behaviour was more pronounced in the PWS group than the T21 group (mean score 13.2 vs. 8.6, p = 0.008). The LRO group spent more hours per week engaged in physical activity (14.7) in comparison with the other groups (9.6 and 9.7), whereas between the groups, differences in time spent in sedentary activities were less pronounced. CONCLUSIONS: Preoccupation with food and low levels of physical activity may contribute to the development of overweight and obesity in some individuals with trisomy 21. These factors warrant consideration in the clinical context.
Journal of intellectual disability research : JIDR, 2016 · doi:10.1111/jir.12259