A growing obesity “class gap” may indicate even greater problems to come.
To all appearances, the widespread war against childhood and adolescent obesity in the United States began in earnest at least five years ago, when Michelle Obama launched ‘Let’s Move!’, a high-profile campaign to tackle the problem. That’s when greater numbers of Americans started to hear the ghastly statistics: Nearly a third of youths overweight or obese. An estimated US$14 billion spent on childhood obesity alone every year.
Now we have the first batch of results from the anti-obesity battlefront. In his State of the Union address on Tuesday night, President Obama delivered the good news about childhood obesity rates declining for the first time in thirty years – “an achievement that will improve lives and reduce health care costs for decades to come.” And on the surface there’s much to celebrate. On the whole, American kids consumed significantly fewer calories in 2010 than they did in 2000, according to the National Center for Health Statistics. Overall, obesity rates among children and adolescents appear to have plateaued and have even ticked down in some parts of the country.
But underneath the aggregate statistics, there’s less heartening news that suggests the anti-obesity message may not be reaching all levels of American society. Findings from our study, published this week in the Proceedings of the National Academy of Sciences (PNAS) my co-authors Carl B. Frederick and Robert D. Putnam of Harvard Kennedy School and I, show the picture that has emerged is socioeconomically skewed. While adolescents from wealthier families indeed saw a drop in obesity rates, obesity among poor adolescents has continued to rise – as though the war on youth obesity had never even been declared for those at the lower end of the socioeconomic scale.
Living in an “Exercise Desert”
Everyone looking to lose weight, not just the obese, will likely be given the same sensible two-part piece of advice: “Eat less; exercise more.” To burn off the pounds, one must expend more calories than one takes in.
Several factors likely play into the obesity gap, among them the rapidly rising cost of fresh fruits and vegetables relative to processed foods, and the relatively high proportion of low-income families living in sprawling “food deserts”, surrounded by convenience stores, but lacking a neighbourhood supermarket. Despite these obstacles, caloric intake declined for all adolescents, wealthy and poor.
What seems to be driving the obesity gap is the difference in exercise habits, not eating habits. We find that poor kids exercise less frequently than their wealthier age-peers. Adolescents with parents educated only to a high school level, reported significantly lower levels of physical participation. While the proportion of wealthy teens who get at least some physical exercise has stayed about the same, the share of poor kids who are physically inactive grew from 10 percent in 2003 to 18 percent in 2011.
Many low-income kids live in neighbourhoods with no parks, recreational centers, or even sidewalks, and where safety is always a concern. Similarly, low-income kids are more likely to live in poor school districts and attend schools were physical education classes have been cut and fewer organised sports are offered – at least without a huge price tag.
Poorer kids may be eating less than they did a decade ago, but the exercise gap appears to have left them stuck with a mounting obesity problem. According to a study published in Pediatrics, obese children are more than four times as likely to become obese adults. For many socioeconomically disadvantaged kids, it may be too late to beat the odds.
By making childhood obesity part of the national conversation, Michelle Obama’s ‘Let’s Move!’ initiative and the many other similarly focused national campaigns launched in recent years may have contributed to the current leveling-off in obesity rates. But the existing efforts may be undercut by deep, complex class inequalities, of which the obesity gap is only one manifestation.
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