WEDNESDAY, Feb. 8, 2006 (HealthDay News) -- Lack of access to exercise facilities, particularly in low-income areas, is one force that's driving the obesity epidemic that's endangering America's children.
But "food insecurity," a term used to describe the feeling generated by not having a guaranteed food supply, doesn't seem to be a factor in the trend.
Those are the conclusions of two studies that appear in the February issue of Pediatrics.
"Our country faces a serious obesity problem -- one that disproportionately impacts poor, minority individuals and communities," said Penny Gordon-Larsen, an assistant professor of nutrition at the University of North Carolina's School of Public Health and Medicine, and the author of the physical activity study. "Our research suggests that perhaps one way to address this would be to argue for greater opportunities for exercise in disadvantaged communities."
The number of overweight American children has more than doubled in the past 20 years. In 1980, about 7 percent of kids were overweight; by 2002, that number had climbed to 16 percent, according to the U.S. Centers for Disease Control and Prevention.
The reason for the increase is both simple and complex. The simple reason is that today's children are consuming more calories than they are expending. But there are many factors driving this change in behavior, and the two new studies sought to define or discredit some of the suspected forces behind childhood obesity.
The first study included geographic and socioeconomic information from across the country. The researchers also gathered statistics on the number of physical-activity facilities and the rate of overweight and average physical activity levels for each area. Physical-activity facilities included schools, public recreation facilities, parks and YMCAs, as well as dance studios and private gyms.
"We found that more disadvantaged communities have a great deficiency in terms of the number and types of exercise facilities available. Working class, minority communities get a double whammy -- they are at greatest disadvantage in terms of exercise facilities and opportunities," Gordon-Larsen said.
Not surprisingly, the lack of places to exercise had on effect on both activity levels and the prevalence of overweight.
The second study, by researchers at Tulane University, included a national sample of nearly 17,000 kindergarten children. Height and weight measurements were taken so the researchers could calculate the body mass index (BMI, a ratio of height to weight) for each child. "Food-insecurity status" was measured using an 18-question test developed by the U.S Department of Agriculture.
Prior studies done with women in "food-insecure" homes had suggested a link between overweight and food insecurity. The suspicion was that people who weren't sure where their next meal was coming from might overeat when food was available, or eat less-nutritious foods that weare higher in calories.
The researchers found that about 11 percent of the children were overweight. However, children from "food-insecure households" were actually 20 percent less likely to be overweight. The risk factors the researchers found that did contribute to overweight were low physical activity, watching more than two hours of TV a day, having a high birth weight, being from a low-income family, and being either black or Latino.
"There are strong arguments for reducing food insecurity among households with young children. This research suggests that these arguments would be based on reasons other than a potential link to obesity," the authors wrote.
Dr. Adam Aponte is a pediatrician and medical director at North General Diagnostic and Treatment Center in New York City who said he wasn't surprised by either finding. Childhood obesity is a problem that needs to be dealt with on many levels -- at home, in school and around the community, he said.
In the area he serves in New York City, safety and access to physical-activity facilities are often issues. He said he advises his patients on ways to get exercise at home, with something as simple as stretch bands. Or, he said, for people who live in apartment buildings, if stairwells are safe, people can walk at least part way up rather than taking the elevator. He said health-care providers can often recommend places, such as a YMCA, that will let children come in and participate, regardless of their income.
"The key is prevention. With children, the younger you start developing healthy lifestyle habits, the easier it is to keep them in good shape," Aponte said.
The American Dietetic Association has tips on ways to get your kids to be more active and improve their diets.