The Global Financial Crisis and Overweight among Children of Single Parents: A Nationwide 10-Year Birth Cohort Study in Japan

Evidence suggests that socioeconomically disadvantaged children may experience a greater increase in overweight risk during macroeconomic downturns. We examined whether inequalities in the risk of overweight between Japanese children from single- and two-parent households increased after the 2008 global financial crisis. We used data from ten waves (2001 to 2011) of a nationwide longitudinal survey following all Japanese children born within 2 weeks in 2001 (boys: n = 15,417, girls: n = 14,245). Child overweight was defined according to age- and sex-specific cut-offs for Body Mass Index (BMI). Interaction between a binary measure of crisis onset (September 2008) and single-parent status was assessed using generalized estimating equation models. Covariates included baseline household income and income loss during the crisis. Girls from single-parent households showed a greater increase in the odds of overweight after crisis onset (adjusted odds ratio (AOR), 1.23; 95% confidence interval (CI), 1.04–1.46) compared to girls from households with two parents, regardless of household financial status. A similar though statistically non-significant trend was observed among boys (AOR, 1.10; 95% CI, 0.92–1.30). Child overweight risk by single-parent status may increase during macroeconomic downturns, at least among girls. Financial aid to single-parent households may not suffice to redress this gap.