Role of Food Insecurity in the Relationship Between Income and Children's Health: Evidence From ECLS-K

Background and Purpose: This study examines the role of food insecurity in the relationship between household income and children's health status. Growing body of recent studies has found that children's health is positively related to family income and the slope of the gradient is stronger for older children than younger children (Case et el., 2002; Murasko, 2008). However, little is known about the mechanisms that underlie the relationship between income and children's health status. Prior research suggests that food insecurity and nutrition may have an important role in explaining the association between income and child health outcomes (Currie et al., 2007). This study fills the gap in previous literature by exploring the link between income, food insecurity, and child health. More specifically, this study examines whether food insecurity has an independent effect on child health status and whether the impacts of food insecurity on child health are stronger for older children.

Methods: Using four waves of data (kindergarten, 3rd, 5th, and 8th grade) from the Early Childhood Longitudinal Study-Kindergarten Cohort (ECLS-K) collected beginning in 1998-99, 6216~ 6,370 children were selected for the analyses. Using the household food security measure from the USDA food security scale, dichotomous marginal food security variable was created for cross-sectional analyses for each grade. For longitudinal models, multiple categories, including permanent food security, transient food security, and permanent food insecurity, were created in order to capture changes in food insecurity status over time. Child health status (1=excellent, 5=poor) was measured by mothers' self-reports. Due to small percent of children classified as being poor health, the responses “fine' and “poor” were collapsed into one category. A rich set of confounding factors, including economic resources, child characteristics, parental, household, and contextual characteristics, were controlled. Ordered probit regression was utilized to estimate the effects of food insecurity on child health for cross-sectional and longitudinal models.

Results: The study has found some evidence that food insecurity is linked to poor child health status, even though a significant income-health gradient remains. The results suggest that food insecurity is significantly associated with increase in the probability of a child being in good health, relative to being in fair or poor health. However, although a tie between health and marginal food security increases between kindergarten and 3rd grade, no evidence was found that the impact of food insecurity increases with child age.

Conclusions and Implications: This study supports that food insecurity plays an important role in the relationship between income and child health. The detrimental impact of food insecurity on child health status adds to a growing body of evidence that food insecurity is a critical public health issue for children. Improving food security will be an effective policy intervention for protecting the health of children.