Low family income and food insufficiency in relation to overweight in US children: is there a paradox?

OBJECTIVES: To investigate associations between family income, food insufficiency, and being overweight in US children aged 2 to 7 and 8 to 16 years, to discuss mechanisms that may explain these associations, and to propose design and data requirements for further research that could effectively examine this issue.
METHODS: Data from the Third National Health and Nutrition Examination Survey were analyzed. Children were classified as food insufficient if the family respondents reported that their family sometimes or often did not get enough food to eat. The prevalence of overweight was compared by family income category and food sufficiency status within age-, sex-, and race-ethnic-specific groups. Odds ratios for food insufficiency are reported, adjusted for family income and other potential confounding factors.
RESULTS: Among older non-Hispanic white children, children in families with low income were significantly more likely to be overweight than children in families with high income. There were no significant differences by family income for younger non-Hispanic white children, non-Hispanic black children, or Mexican American children. After adjusting for confounding variables, there were no differences in overweight by food sufficiency status, except that younger food-insufficient girls were less likely to be overweight, and non-Hispanic white older food-insufficient girls were more likely to be overweight than food-sufficient girls (P<.10).
CONCLUSION: Further research to evaluate whether food insecurity causes overweight in American children requires longitudinal quantitative and in-depth qualitative methods.