Child obesity persists among the poor and less educated; early-life factors also matter; Kentucky's rate is high

Although youth obesity has become slightly less prevalent, most of the improvement has been restricted to children in families with higher salaries and educations, according to a Harvard University Kennedy School of Government analysis by Robert Putnam and colleagues. They examined data pertaining to education and income from the 1988-2010 National Health and Nutrition Examination Surveys and the 2003-2011 National Survey of Children's Health, Joe Rojas-Burke writes for Covering Health, published by the Association of Health Care Journalists.

Childhood obesity is at 18 percent in Kentucky—one of the highest in the country—and 35.7 percent of children ages 10 to 17 are overweight or obese, according to the Kaiser Family Foundation. Nationally, rural children are more likely to be obese than those in cities and suburbs. 

Obesity in children whose parents have a college degree began falling about 10 years ago, but increased among children whose parents have a high-school degree or less. There were similar findings among income levels, and the trend was also found in non-Hispanic whites. Although calorie intake did not vary much by education or wealth, physical activity varied greatly. "Children of college-educated parents became more active than they were a decade ago, while children of less educated parents showed no improvement. One factor in this trend is that children from families with high education and incomes are playing increasingly more high-school sports, and children from poorer, less educated families have been playing fewer high-school sports.

Some believe that obesity is an issue in low-income neighborhoods because their lack of parks, recreational centers, outdoor trails and safety discourage physical activity. However, there isn't much evidence to support that claim, and "The effects of income and education tend to trump the influence of neighborhood characteristics," Rojas-Burke writes. Does an outdoor environment convenient for physical activity always pull children away from their video games and Internet?

People often seem to forget that factors from very early in life can influence and individual's likelihood of becoming obese. According to the Early Childhood Longitudinal Study, which followed 7,738 kindergarteners for 10 years beginning in 1998, half the children who became obese were already overweight in preschool, and that doesn't include the 12 percent who were already obese in kindergarten, researchers reported in the New England Journal of Medicine. "Overweight 5-year-olds were four times as likely as normal-weight children to become obese by the end of the study," Rojas-Burke writes.

Sometimes factors before a person is born can make a difference. According to the authors of the NEJM paper, children with high birth weights were only 12 percent of the population but represented more than 36 percent of people who were obese at age 14. A pregnant mother's undernourishment or overnourishment can alter fetal metabolism and brain development, which may contribute to obesity. "Observational studies have linked bottle-feeding rather than breast-feeding to weight gain," Rojas-Burke repots. Societal changes have made it more difficult for children to stay healthy. Food companies are making more and more high-calorie, low-nutrient foods. A common concern—insufficient sleep—even affects toddlers, and it can interfere with the regulation of hormones. These factors and others likely vary depending on family income, education and cultural background. (Read more)