The mental health of obese children should be a primary focus of researchers studying childhood obesity, according to Christine Calamaro, PhD, CRNP, assistant professor at the University of Maryland School of Nursing.
Calamaro, a leading research scientist in pediatric nursing, says, "My interest in this is not just about the weight of our kids anymore. It is about all the problems associated with obesity. When you start talking about adolescents [emerging] into adulthood, you have to consider co-morbidities, such as depression and diabetes."
In the past 40 years, the number of obese children has increased four-fold, according to the National Institutes of Health (NIH), now reaching 17 percent of children and adolescents ages 2-19 years.
Much recent research on obsese children has focused on a link between lack of sleep duration or quality of sleep. Calamaro says, "We know there is a link, but what are the things causing it?" Her biggest worry is that children and adolescents who stay awake more and sleep less have impaired physical and mental health.
"It only makes sense to me that if they are not sleeping well, or have fragmented sleep, then their endocrine balance is screwed up, all their hormones are screwed up, their cortisone levels are higher because they are tired and stressed, they are hungry, they eat more, they get carbohydrate-rich foods to get the instant glucose increase, they can get insulin resistance because of weight gain, then eat more carbs to stay awake. It's a vicious cycle."
Yet lack of sleep is not the lone culprit. Calamaro led a recent study of 13,568 adolescents from 12 to 18 years old. Those sleeping six or fewer hours a day were no more obese than adolescents sleeping longer. The finding, part of the a study published in the Journal of Sleep Research, runs counter to a hypothesis common in adolescent health research, according to Calamaro.
The researchers at first were disappointed. They had expected "a slam dunk" relationship between lack of sleep and obesity, she says. But the study also revealed that other negative factors were at work. "In light of other recent analyses that demonstrated a consistent increase in obesity among short sleepers in children and adults, the results of this study raise more questions about the causal pathways that may lead to increased adiposity [obesity]in adolescents."
The study showed an association between sleep duration and depression. Depressed adolescents tended to sleep less than non-depressed adolescents, both in a 12-to-14 age group and in a 15-to-18 age group. Depressed adolescents were almost twice as likely to be obese whereas adolescents who watched television excessively were 37 percent more likely to be obese.
Calamaro and co-authors also found that early adolescents who had watched more than two hours of TV were 36 percent fatter in later adolescence than those watching less TV. "Television viewing may lead to increased risk of obesity because watching television has been associated with increased dietary intake, leading to an imbalance in energy expenditure," the authors wrote. Television watching for about two hours per day at the younger age of 12 to 14 was predictive of obesity when they were 15 to 18.
"Childhood obesity is a very complex problem we must address," says Jay A. Perman, MD, pediatrician and president of the University of Maryland in Baltimore. "It is going to take more than health care providers to fix. Physicians, nurses, social workers, attorneys, pharmacists and others need to solve the problem together."
Last year, NIH launched a major effort of $72.5 million in new research funding to examine ways to curtail the nation's growing childhood obesity epidemic. According to the NIH website: "Factors behind this increase are believed to include increased consumption of high-calorie food and drinks and less physical activity during and after school. Overweight and obese children are at higher risk of chronic diseases during childhood and adulthood, including heart disease, stroke, asthma, type 2 diabetes, and several cancers."
Despite more funding, experts are not catching up with the problem, says Calamaro. "Preventative care is just not reimbursable [from insurance providers] as much as it should be. In health care we need to focus more on children. By 2043, half the adult population will be obese in the United States" if trends continue and changes are not made, she says.
"Today, with the current generation of children, by the time the parents capture it, it is too late," says Calamaro. "It is difficult. So what we do know is start in infancy. A chubby baby is not a healthy baby. To try to get parents to see that is difficult.
"We in the primary care setting need to be reinforcing this message about healthy eating/healthy sleep every time parents and children come into the doctor's office. The hardest thing with obesity is to start the minute that baby first comes into your office and to talk about what healthy eating is for that child: Are you feeding that baby properly with that bottle? When does it look like they are finished drinking from the bottle? Are they warm? Are they dry? Are they crying because they are hungry, or are they crying because babies cry? Basic baby knowledge reinforced over and over again."