Hollar said the study also reflects the link between socioeconomic status and obesity. And inextricably tied to this is the differences in childhood obesity among various racial groups. Forty-eight percent of the children in the study were Hispanic, most of whom Hollar said came from working class families whose parents often didn't have the time, energy or money to encourage healthy diet habits at home.
It's not the first study to find a link between race and childhood obesity risk. According to the 2005 study "Preventing Childhood Obesity," published by the Institute of Medicine, the highest prevalence of childhood obesity in America occurs in the Hispanic and African-American populations.
In many cases, economic hardship experienced by a disproportionate number of these families may be to blame.
"A lot of these parents were working double shifts and didn't have the time or money to cook healthy meals at home, and since these are elementary children, they can't go out and buy their own food," Hollar explained. "So our hope is that the children will become more accustomed to these healthy eating and living habits with each school day and they will take that message home to teach their parents."
Moreover, a study published this month in the journal of the American Dietetic Association finds that the cost of healthy eating is often too high for low-income families, who would have to devote 43 percent to 70 percent of its food budget to fruits and vegetables to meet the 2005 Dietary Guidelines, which recommends five to nine servings of fruits and vegetables a day.
Leaders of the HOPS study tailored the program for low-income families by sending home newsletters to parents with tips for healthy living, including affordable recipes and simple dietary changes that could be easily incorporated into their busy lives, such as adding low-fat granola to salads instead of croutons, or adding sweet potatoes to a bowl of soup instead of cheese and salt.
"We need to enhance awareness of parents, and their passion for protecting the health of their children," said David Katz, associate professor of public health and associate director of the Nutrition Science, Rudd Center for Food Policy & Obesity at Yale University. "Then, we must empower them with tools, knowledge, skills and resources that allow them to do so."
But Katz adds that the childhood obesity epidemic affects families across the racial and socioeconomic board. And the stakes are high; obese children are 70 percent more likely to grow into obese adults, and they are at high risk of developing high blood pressure, high cholesterol and Type 2 diabetes.
"No question, the situation is worse in poorer households. But the middle class is not doing very well either," Katz explained. "This problem is nondenominational. There are disparities, but everyone is caught up in the epidemics of obesity and diabetes, and everyone must play a role in meeting the challenge successfully."