Experiencing constant stress and the inability to cope with it can increase the risk of obesity in children, according to a new study.
Researchers from Penn State and Johns Hopkins University found a child's biological response to stressor easily predicting whether he/she will put on unnecessary weight or not.
"Our results suggest that some children who are at risk of becoming obese can be identified by their biological response to a stressor," Lori Francis, associate professor of biobehavioral health, said in a news release. "Ultimately, the goal is to help children manage stress in ways that promote health and reduce the risks associated with an over- or under-reactive stress response."
The study included 43 children, aged between five and nine and their parents. All the children underwent the Trier Social Stress Test, and were subjected to a five-minute anticipation period and 10-minutes stress period. The stress period required the children to deliver a speech and complete a mathematics task.
After the test, the researchers measured the level of the stress hormone, cortisol, in children's saliva and compared it to the hormone levels before they participated in the stress test.
The children were then given lunch and were asked to record their hunger levels. They were given the option of 10 snacks, toys and activities. The children's choice of food was monitored and measured using the Free Access Procedure.
Researchers found children with higher levels of cortisol, having high BMI and eating high calorie snacks when they were already full and not hungry.
"We found that older kids, ages 8 to 11, who exhibited greater cortisol release over the course of the procedure had significantly higher body-mass indices [BMI] and consumed significantly more calories in the absence of hunger than kids whose cortisol levels rose only slightly in response to the stressor," Francis said. "We also found that kids whose cortisol levels stayed high-in other words, they had low recovery-had the highest BMIs and consumed the greatest number of calories in the absence of hunger."
Findings of the study have been published in the journal Appetite.
The revelations come at a time when childhood obesity has more than tripled in the United States over the past 30 years. A Centers for Disease Control and Prevention (CDC) report shows a shocking increase in the number of obese children aged six to 11, from 7 percent in 1980 to 20 percent in 2008.
