Although the prevalence of obesity in children and adolescents began to stabilize from the 2000s in the United States, the problem continues to worsen among young Americans of lower social classes.This is the conclusion of a study by researchers at Harvard University and published in the American journal “Proceedings of the National Academy of Sciences” (PNAS). The results were based on two national surveys that collected data on the prevalence of obesity among children and adolescents between 1988 and 2011.For the authors of the study, the socioeconomic context exerts a strong influence on the individual’s physical activity patterns and food consumption. “Not only fresh fruits and vegetables are more expensive than fast food, but also healthier alternatives are sometimes harder to find in poor neighborhoods,” the article says.The graph of obesity among American adolescents aged 12 to 17 years seems to have begun to stabilize from the mid-2000s. Data collected between 1988 and 1991 point to a rate of 9.1% of obese adolescents in the United States. This percentage jumped to 17% in data collected between 2003 and 2004. In a new survey conducted between 2009 and 2010, the share of obese youth remained the same: 17%.Between 2000 and 2010, calorie consumption among boys aged 2 to 19 years fell by 7%. Among girls, the drop was 4% over the same period.InequalityThe point is that this decline is not occurring equally among the different social classes. The data show that among adolescents whose parents completed higher education, the level of obesity has declined. Already among adolescents whose parents only studied until high school, the level of obesity continues to rise.According to the researchers, this reflects both the lack of access to healthy food for the poor as the lack of options and stimulation for physical activities of this population.In 2011, for example, 91% of adolescents whose parents had higher education reported having had at least 20 minutes of continuous physical activity in the past seven days. Among those whose parents have only high school, this percentage was 80.4%.