Patterns of Food Stamp and WIC Participation and their Effects on the Health of Low-Income Children

Year: 1999

Research Center: Joint Center for Poverty Research, University of Chicago and Northwestern University

Investigator: Lee, Bong Joo, Lucy Mackey-Bilaver, and Robert M. Goerge

Institution: Chapin Hall Center for Children, University of Chicago

Project Contact:
Bong Joo Lee, Ph.D.
Chapin Hall Center for Children
University of Chicago
Chicago, IL 60637


The primary purposes of this study are to examine: 1) the patterns of program participation in the Food Stamp Program (FSP) and the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) during 1990-98, the time of welfare reform in Illinois and 2) the effects of WIC on young children’s health outcomes. The authors use a unique linked data set based on population-level administrative data on all births, food stamp and WIC participation, and Medicaid eligibility and claims in Illinois between 1990 and 1998.

Lee et al. estimate that about 65 percent of all children born in Illinois during the study period and observed for 5 years (i.e., those born between 1990 and 1993) received either WIC, food stamps, or Aid to Families with Dependent Children (AFDC)/Temporary Assistance for Needy Families (TANF) by age 5. While this overall program participation rate changed very little across birth cohorts, the authors found a considerable shift in participation patterns across the three programs. As welfare reform was implemented in Illinois, both FSP and AFDC/TANF participation rates declined substantially, while WIC participation rates continued to increase. Further, most of the decrease in food stamp participation was due to drops in entries to TANF.

The authors found some evidence to suggest that in recent years, families have been forgoing food stamps and turning more to WIC for essential food items for their young children. Increases in WIC funding alone do not explain the increase in WIC participation during the study period, as the rate of WIC funding increase declined while the rate of WIC participation increase continued to climb. They also found that spells of participation for both food stamps and WIC have become shorter in recent years, although shorter spells are more noticeable in the Food Stamp Program than in WIC.

Two findings relate to the effects of WIC on health services and outcomes in this study:

  • Among children enrolled in Medicaid, WIC participants are significantly less likely to be diagnosed with health problems associated with inadequate nutrition (failure to thrive and nutritional deficiencies) than are nonparticipants. However, WIC participation had no effect on the probability of a child subsequently being diagnosed with anemia.
  • Children in WIC are more likely to receive preventive health care services, measured as an initial well-child exam received through the Early Periodic Screening, Diagnosis, and Treatment Program (required of State Medicaid programs through Title XIX of the Social Security Act), than are those not in the WIC program.

Lee et al. conclude that their findings of positive WIC program effects combined with declining rates of participation in the Food Stamp program suggest a growing need for coordination among the assistance programs to best meet the food and nutritional needs of low-income families with young children.