Several encouraging reports from the last two years indicate that America is making some headway in the fight against youth obesity. But a new study by Harvard researchers suggests that the gains have been economically stratified — and the obesity rate is actually increasing for poor adolescents, even as it falls among teenagers with affluent and more-educated parents.
A 2013 report from the Centers for Disease Control (CDC) found that the obesity rate for poor children fell in 18 states and the Virgin Islands between 2008 and 2011 — a remarkable reversal from the previous three-year period, which saw rates rise in 24 states. But the Harvard researchers found that the obesity rate among teenagers aged 12 to 17 with parents who only had a high school education — and were consequently poorer — actually increased by 25 percent between 2003 and 2010. By contrast, adolescents whose parents had a four year college degree saw their incidence of obesity slashed in half over that same time period, from 14 percent to seven percent.
The Harvard researchers also noted that the rich-poor gap persisted despite the fact that children from low-income and lesser-educated households actually ate less calories than more affluent adolescents. They speculated that a major reason for this is that poorer teenagers report exercising less and are less likely to be part of a sports or athletic program — likely because such children don’t live in areas with an abundance of affordable recreational options, or attend schools with limited resources for physical education programs.
Another possible explanation is that the calories being consumed by poorer and less educated families, while lower in absolute terms, are more likely to stem from pre-processed or junk foods laden with salt, sugar, and fat. These are often the only types of food that lower-income families have access to or can easily afford on a strained food budget.
A separate 2013 study by researchers at the University of Georgia suggested another rationale for lopsided obesity rates among the rich and the poor. Lead study author Gene Brody found that poor young teenagers who do well in school, are in good mental health, and are socially well-adjusted actually end up with an excess of stress hormones because of the strains of overcoming economic adversity. Consequently, these teenagers are more susceptible to obesity, hypertension, stroke, and cardiovascular diseases from a younger age.
These results are actually a microcosm of a worldwide trend. The Overseas Development Institute recently found that obesity rates have been rising sharply in developing nations, even as they fall in affluent nations.