Nine-year-old children who were chronically exposed to such stressors as poverty, crowded housing and family turmoil gain more weight and were significantly heavier by age 13 than they would have been otherwise, a new study has found. The researchers suggest the reason is that ongoing stress makes it tougher for children to control their behavior and emotions -- or self-regulate. That, in turn, can lead to obesity by their teen years.
The researchers measured the height and weight of 244 9-year-olds in rural New York state and calculated their various physical and psycho-social stressors -- for example, exposure to violence, living in a substandard house or having no access to such resources as books. They also measured the children's ability to delay gratification by offering them a choice between waiting for a large plate of candy versus having a medium plate immediately. The researchers measured the children's height and weight again four years later.
While the study doesn't prove that a child's inability to delay gratification causes her to gain weight, there's strong evidence to suggest that it does, according to Gary Evans, an environmental psychologist at Cornell University, and a co-author of the study . First, previous studies have shown that chronic stress is linked to weight gain in children and teenagers, and that children eat more sugary, fatty foods when stressed. Second, there's a plausible neurocognitive mechanism that may help better understand this behavior, Evans said. "There's some evidence that parts of the brain that are vulnerable and sensitive to stress, particularly early in life, are some of the same parts involved in this self-regulatory behavior."
The study appears in the journal Pediatrics.