Under the one child policy regime in China: did having younger sibling(s) increase the risk of overweight and underweight status?

Abstract

The implications of having any younger sibling(s) on child overweight and underweight status under China’s One Child Policy Regime are complicated by multiple factors, including potential resource dilution, the stage of economic development, changing child-rearing norm, mandated birth interval and parental son preference. Using the instrumental variable method and data from China Health and Nutrition Survey 1991–2006, we find that having younger sibling(s) generally does not affect a firstborn child’s risk of being overweight or obese, neither does it increase the risk of being underweight. The findings on underweight status suggest that the favourable effect of economic growth and child rearing practice have outperformed the resource dilution effect in basic nutrition needs through the years of the study. It implies that further relaxation of the One Child Policy should not increase the nutritional risk for children.