UNIVERSITY PARK – Some low-income mothers are more likely than others to introduce their infants to cow’s milk too soon. In doing so, they may put their children at risk of health complications, according to a study by researchers at Penn State and the Institute for Children and Poverty, New York.
The study showed that women who enrolled in the U.S. Department of Agriculture’s WIC program during their first or second trimester of pregnancy — from week one to week twenty-seven — were far less likely to introduce cow’s milk too soon than women who enrolled in WIC during their third trimester or who did not enroll at all.
“What this study tells us is that if we intervene by enrolling low-income women in WIC earlier on in their pregnancies, it will be healthier for the babies,” said Daphne Hernandez, assistant professor of human development and family studies, Penn State.
The researchers analyzed WIC enrollment by trimester of pregnancy. Past studies have only looked at whether or not women had enrolled in the program. The study is helping researchers to better understand the critical time period in which proper nutrition can be reinforced in low-income women, which will have lasting effects in improving their children’s health. The researchers reported their results in a recent issue of the Journal of the American Dietetic Association.
Although many adults drink cow’s milk, it can be harmful to infants’ health. The American Association of Pediatrics recommends that children not drink cow’s milk before their first birthday. In addition to being difficult for infants to digest, cow’s milk is much lower in iron than breast milk and formula, which means that infants who are fed cow’s milk are at an increased risk for developing anemia or other iron deficiency disorders.
Hernandez hypothesizes that women who enter WIC by their second trimester may be influenced by dietary information provided to them by WIC. The study used data from the Early Childhood Longitudinal Study, Birth Cohort — a nationally representative longitudinal study of children born in 2001. The researchers found that low-income mothers were also far more likely to formula feed rather than breastfeed their infants. Breast milk has other benefits over formula and cow’s milk. It contains antibodies that can boost infants’ immunity, it can provide emotional benefits for baby and mother and it can help mothers lose post pregnancy weight. Because of the evidence for the positive effects of breast milk, WIC encourages mothers to breastfeed. However, Hernandez believes the low breastfeeding rate among WIC participants is related to the lack of proper facilities to pump breast milk at low-wage jobs sites.
“We need to rethink the environment of low-wage jobs by taking a closer look at who is being hired and what public programs are available to them to see if there’s a disconnect between low-wage job facilities and advice that is delivered by public programs,” said Hernandez.
Hernandez believes that doctors and employers can learn from this study and that they can provide access and information to mothers to improve their infants’ health.
“If doctors know that a pregnant patient is economically disadvantaged, they can help get the patient enrolled in WIC sooner. It can be as simple as providing them with an application form or showing them a list of grocery stores that accept WIC dollars,” she says.
The U.S. Department of Agriculture and the Robert Wood Johnson Foundation supported this work.
Liam Jackson, Penn State University
