National WIC Association

Health Outcomes Associated with WIC Participation

WIC has the potential to influence health outcomes during pregnancy, infancy, early childhood, and the inter-pregnancy period. The following section outlines needed areas of research of the impact of core WIC nutrition services across each developmental stage.

WIC and Pregnancy
WIC has an opportunity to reach women before they give birth. Research-informed strategies to improve prenatal participation in WIC need to be evaluated. Previous research has reported protective associations between WIC prenatal participation and different birth outcomes, including preterm birth and low birthweight (<2,500 grams). New research to examine the consistency of these previous associations using study designs that minimize the potential for selection bias is needed. Areas of research include using comparable non-WIC comparison groups and incorporating strategies to determine whether the timing of prenatal enrollment (i.e. enrollment during 1st trimester, 2nd trimester, or 3rd trimester) affects specific birth outcomes.

WIC and Infancy
Cross-sectional and longitudinal studies are needed to further investigate the relationship between participation during infancy and a host of outcomes, including health status, breastfeeding patterns, nutritional deficiencies (e.g., iron-deficiency anemia), infant hospitalizations in the first year of life, and infant mortality. Further studies are also needed to explore the associations between infant feeding practices and childhood overweight and obesity among children who participated in WIC during this period.

WIC and Early Childhood
The goals of child participation in WIC are to ensure that young children are guided in a positive health trajectory and are kindergarten-ready. WIC nutrition services aim to impact the nutrient adequacy, and overall health of children. Research is needed to determine how the WIC food package and accompanying nutrition education impact participant and family behavior change and how these changes, in turn, influence health outcomes.
The transition from breastmilk and/or infant formula to complementary foods through infancy and early childhood is an important milestone for families. WIC nutrition education and the food package are building blocks to help an infant transition from being breastfed or formula-fed to consuming healthy meals. This transition is not always easy. WIC nutrition professionals provide education and support to help parents improve family health behaviors through food choices. Research is needed to assess optimal methods for WIC to support parents to successfully introduce complementary feeding and adapt healthy behaviors and nutritional health long-term.
In addition, multiple components of WIC directly address childhood obesity and must be carefully evaluated. WIC anthropometric data have the potential to continue to fill an important data gap in the evaluation of national, statewide and local obesity prevention efforts, especially those targeting low-income, high-risk communities. Further studies are needed to explore the associations between breastfeeding, healthy growth during early childhood, and risk factors for obesity.

WIC and the Inter-Pregnancy Period
WIC has the unique opportunity to interact with women between pregnancies to help improve their own health as well as positively influence the outcomes of future births. Designing, testing, and evaluating postpartum health messages or interventions tailored to a woman’s health, nutritional, and breastfeeding status, as well as her future pregnancy plans, is an important area for research. Creating and evaluating partnerships with behavioral or mental health professionals to address maternal depression is another critical area for research.