Socio-Economic Patterns in Overweight from Adolescence through Adulthood in the United States

Overweight among adolescents is a growing health problem in many countries, especially in the United States. The current study examines socioeconomic-related inequality in overweight and obesity over time among young Americans using the methodology of the Erreygers adjusted concentration index. The changes in the concentration index of obesity are decomposed into obesity-related income mobility (MR) and income-related obesity mobility (MH). The analyses from adolescence through adulthood are examined based on surveys from the National Longitudinal Study of Adolescent Health (ADD Health). The descriptive results show a significant increase in both overweight (10.5 p.p) and obesity (27 p.p.) prevalence from adolescence (11-22 y) to adulthood (24-34 y). The results of the Erreygers index show that socioeconomic-related inequality in overweight is not statistically significant in this study, except for males. For obesity, there is a statistically significant negative Erreygers index found, except for males in the last period (adulthood). Overall, individuals show a stronger negative degree of socioeconomic inequality in obesity at adult ages compared to younger ages, referring to a larger concentration of obesity among low-income groups during adulthood. In addition, the change in the Erreygers index of obesity can rather be attributed to income-related obesity mobility (MH) than to obesity-related income mobility (MR). This suggests that the increase in the Erreygers adjusted concentration index is more likely caused by transitions into obesity among the initial poor (MH) than to reranking of incomes (MR). Despite the lower contribution of MR, the results still show a significant contribution, where obesity is associated with downward income mobility. Overall, both mobility components were harmful for low-SES groups, referring to an increase in obesity over time among the poor.