International comparisons of childhood obesity prevalence and income inequality in developed countries

Overweight and obesity rates are rising among children and adults and are garnering significant attention worldwide in connection with rising chronic disease rates. Concurrently, more countries are experiencing growing income inequality, increasing negative health outcomes for those in poverty. The purpose of this study was (1) to determine the association between childhood obesity and income inequality and (2) to examine the relationship among childhood obesity prevalence, income inequality, adult obesity prevalence, socioeconomic status, household income, education, the built environment, and food access. This study used Organization for Economic Cooperation and Development (OECD) Health data sets from 1997-2011 to determine the association between childhood overweight and obesity rates (measured by age-adjusted BMI and percent prevalence) and income inequality (quantified by the GINI index) within OECD nations. Data collected from 29 OECD member countries between 1997-2011 resulted in a positive correlation (r = 0.61) between measured overweight prevalence and GINI coefficients. Existing literature of individual contributing factors was analyzed to provide support for the correlation between BMI and income inequality and to explain the interconnected and ongoing relationship between the two. Adult obesity, socioeconomic status, income inequality, household income, education, the built environment, and food access were all significantly predictive of childhood obesity rates. Analysis of these individual factors provides support and direction for policy and program implementation. Simultaneously, this study illuminates a need for more comprehensive and consistent collection of childhood obesity data both on a national as well as international scale to address this health concern.