Policy Implications of WIC or Food Stamp Program Participation on Children’s Diet Quality and the Risk for Childhood Obesity

Year: 2006

Research Center: Department of Nutrition at the University of California, Davis

Investigator: Kranz, Sibylle, and Jill Findeis

Institution: Pennsylvania State University

Project Contact:
Sibylle Kranz
Department of Nutritional Sciences
Pennsylvania State University
5G Henderson Building
State College, PA 16802
Phone: 814-865-2138
Fax: 814-865-5870


Federal food and nutrition assistance programs, such as the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) and the Food Stamp Program, target low-income families and provide food to participating individuals. Changes in consumption of food and nutrients associated with health goals, particularly in the child population, include the need to increase the dietary intake of fruits, vegetables, dairy and calcium, and whole grains and to decrease the intake of added sugar. The dietary intake recommendations for these foods have changed in the recent past and are included in the newly proposed WIC food package in an effort to improve child nutrition.

Dietary intake patterns are not only an important predictor of children’s health but also track into adulthood.

Development of healthy eating patterns early in life is an important tool to prevent chronic diseases, such as diabetes and cardiovascular disease in adults. Because the obesity epidemic affects not only adults but also children, Federal nutrition assistance programs may serve a dual purpose. Foremost, the programs are a venue to increase the availability of food in low-income families, but may also increase access and consumption of high-quality foods to prevent the development of obesity and other chronic diseases.

Current research indicates that children participating in WIC are more likely to meet the dietary intake recommendations for nutrients than nonparticipants. WIC participation has also been shown to improve children’s eating patterns, significantly reducing the amount of snacking and the intake of added sugar from snacks, reducing overall added sugar intake, and increasing the likelihood of meeting the Dietary Reference Intake (DRI) for dietary fiber.

No single food or nutrient is representative of total diet quality. Thus, a composite diet quality assessment score was developed and updated to reflect the latest Federal dietary intake recommendations. The Revised Children’s Diet Quality Index (RC-DQI) includes 12 individual nutritional components, and 1 item to indicate overall energy balance, to determine the quality of the average dietary intake in children ages 2-18. Dietary intake of added sugars, total fat, specific fatty acids (linoleic acid, linolenic acid, EPA, and DHA), total grains, whole grains, fruits, vegetables, 100-percent fruit juice, dairy, and iron was used to determine whether children consume optimal levels of these key nutrients and foods. In addition, an energy balance component consisting of two subcomponents was introduced. The first subcomponent expressed the ratio between children’s actual and ideal energy intake (as estimated using the age- and gender-specific Estimated Energy Requirements (EER) of the DRI). The second expressed the average number of hours spent watching television compared with the hours for television and computer time recommended by the American Academy of Pediatrics.

Socioeconomic, nutrition, and medical examination data on children 2-18 years old (n=7,546) from the National Health and Nutrition Examination Survey (NHANES) 1999-2002 were employed to examine the diet quality of American children. All analyses were conducted using STATA 9.2, which allowed for correction of the complex survey design and sampling techniques to maintain the nationally representative character of the data.

Validation of the index showed that increasing RC-DQI scores, representing better diet quality, were associated with improved values of indicators of overall health, such as obesity status and blood cholesterol and total triglyceride levels.

Total RC-DQI point scores ranged from 0 to 82, with younger children having better diet quality than teenagers. Four percent of preschoolers had between 90 and 100 percent of the possible RC-DQI points, and only 10 percent scored less than 50 percent of the possible points. School-age children and teenagers, on average, scored much lower, and none of either age group scored more than or equal to 90 percent of the possible points. Forty-six percent of children ages 12-18 and 31 percent of children ages 6-11 scored less than 50 percent of the possible points.

The study examined whether participation in Federal food and nutrition assistance programs could predict that American children were at “risk to be overweight” or “overweight.” A multivariate regression was conducted using nationally representative data for children ages 2-18 (NHANES 1999-2002), controlling for children’s age, gender, physical activity level, ethnic group, household income, preschool and school attendance, and school breakfast and school lunch participation.

Results indicated that WIC participation significantly improved children’s overall diet quality. For children who participated in WIC, the risk of being overweight was reduced by 40 percent compared with children who were income eligible who were income eligible for WIC (poverty-income ratio (PIR) less than 1.3) but did not participate. For children eligible for food stamps (PIR less than 1.3), the effect was even more beneficial: Children who participated in WIC were 57 percent less likely to be overweight than children in the same income group who did not participate in WIC.

Due to the dual problems of malnutrition and overweight (from overconsumption of energy or lack of physical activity), public policy on food and nutrition assistance programs must be re-evaluated regularly to assess whether the assistance provided addresses both of these issues. Data in this study indicate that the WIC program significantly affects young children. WIC participation not only improves preschoolers’ diet quality but decreases the risk for childhood obesity. Encouraging WIC participation in the low-income population may be an effective public policy strategy to help prevent childhood obesity and therefore to reduce the risk of chronic diseases not only during childhood but also later in life.