The Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) provides food and nutritional advice to low-income women, and infants and children, who are income eligible and are nutritionally-at-risk. The effects of WIC on infants have been extensively studied, but children one to four are the most rapidly growing part of the WIC caseload, and little information is available about the effects of WIC on this group.
Using data from the 1996 and 2001 panels of the Survey of Income and Program Participation (SIPP), we show that Medicaid policies that affected take up among infants had long term effects on participation in the WIC program. By contrast, increases in the generosity of Medicaid towards older children increased WIC eligibility without having much impact on participation. Hence increases in WIC participation among children have not been driven by higher income families made eligible as a result of SCHIP, as some critics have argued.
Our most striking finding is that WIC participation at age four has large and significant effects on the probability that a child is at risk of overweight (i.e. had BMI greater than the 85th percentile for sex and age). This suggests that either the nutrition education or the actual provision of healthy food is helping to prevent obesity among young children. This is an important measure of the success of the WIC program because of the importance of obesity as a public health threat, and because of the importance of establishing healthy eating habits early in life.