Randomized, Controlled Trial to Examine the Impact of Providing Yogurt to Women Enrolled in WIC

Abstract 

Objective

Examine the impact of providing yogurt to women enrolled in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).

Design

Randomized, controlled intervention trial.

Setting

Two California WIC local agency sites.

Participants

511 pregnant, breast-feeding, or postpartum women.

Intervention

Substitution of part of the WIC milk allowance with yogurt accompanied with educational materials.

Main Outcome Measures

Participants' consumption and attitudes regarding yogurt provision.

Analysis

Chi-square, Fisher exact, and Student t test to compare pre- versus post-intervention responses. Nonparametric Wilcoxon, chi-square, and t test to compare changes in response in intervention versus controls. Analysis of covariance models to test the influence of language preference on outcomes.

Results

Over 86% of women wanted to substitute some of their milk vouchers with yogurt. Among these, 62% reported preferring yogurt to milk. The majority (89%) redeemed the yogurt coupons. Compared to controls, intervention women reported a trend (P = .09) toward an increase in yogurt intake of 1.0 fl oz/day while not decreasing other dairy consumption. Those in the intervention group with the lowest tertile of yogurt intake at baseline increased yogurt consumption by 2.8 fl oz/day (P = .003) relative to controls with lowest intake.

Conclusions

Yogurt is likely to be a popular substitute for milk and could contribute to increased dairy intake among women if it were an option in WIC.

Key Words: dairy, yogurt, women, WIC, low-income, nutrition education, dietary intake