Date of Award
2024
Degree Type
Dissertation
Degree Name
Doctor of Philosophy in Health Sciences
Specialization
Nutrition and Food Sciences
Department
Nutrition and Food Sciences
First Advisor
Alison Tovar
Second Advisor
Maya Vadiveloo
Abstract
Maternal diet plays a critical role during the perinatal period, impacting both short- and long-term health outcomes in women and their children. Lower-income individuals are at higher risk of having a low diet quality. Therefore, the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) aims to reduce the negative impacts of low socioeconomic status on the diet of its participants (low-income pregnant and postpartum women and children up to age 5) to promote optimal short- and long-term health outcomes. Numerous studies show that WIC improves children’s diet quality, but associations in women have been insufficiently evaluated. While there is some evidence that prenatal participation in WIC may improve diet quality, the few studies that evaluate WIC-participating women’s diet focus on changes pre- vs. post-implementation of the latest (2009) food package revision, but not how their diet compares to non-participants. Moreover, state-level reports estimate that <18% of WIC families fully redeem their food benefits, suggesting that most WIC participants do not obtain all the nutritional benefits that WIC is designed to provide. Well-known barriers associated with reduced redemption of WIC food benefits include transportation issues, confusion over WIC product eligibility, and category-specific limits, thus potentially hindering the improvement of participants' diet quality.
In sum, numerous barriers may hinder the improvement of WIC-participating women’s diet quality by reducing the full redemption of WIC food benefits. With the implementation of online food shopping for WIC, there is an opportunity to employ choice architecture techniques in online environments to promote WIC benefit redemption and, by extension, improve diet quality. Therefore, two studies were conducted to evaluate the diet quality of WIC-participating women and pilot-test the feasibility and acceptability of an online intervention to improve WIC food benefit redemption and the quality of grocery store purchases among WIC-participating women.
The first study was a cross-sectional, secondary analysis of the 2011-2018 cycles of the nationally representative National Health and Nutrition Examination Survey (NHANES) that compared the diet quality of WIC-participating women, WIC-eligible nonparticipating women, and income-ineligible pregnant and postpartum women (n=626) using the Healthy Eating Index-2015 (HEI-2015). Multivariable Tukey-adjusted linear models were used to compare HEI-2015 total and component scores between groups. Models were adjusted for age, pregnancy and postpartum status, breastfeeding status, race and ethnicity, and food security. Results showed no differences in diet quality between groups for total and most component scores and that the diet quality of reproductive-aged women in the U.S. is suboptimal. Therefore, more research is needed to evaluate the mechanisms through which WIC could impact maternal diet quality.
The second study was a mixed-methods pilot randomized-controlled trial with qualitative, in-depth interviews to assess the feasibility and acceptability of a WIC-tailored pre-filled online grocery shopping cart to help improve WIC food benefit redemption and the diet quality of grocery store purchases of WIC-participating women. Rhode Island WIC participants (n=24) completed a baseline questionnaire and a simulated shopping episode (SSE), shopping as if using all their food benefits and buying WIC and non-WIC items to last ten days. After a week, participants were randomized into the intervention (personalized, modifiable carts pre-filled with 100% of the 2022 proposed WIC package) or control (selected their items individually) groups before completing the second SSE. Both groups had benefit lists and WIC labels. Feasibility was assessed via process data and percent agreement to feasibility questions, and acceptability via percent agreement to acceptability questions and post-intervention qualitative interviews. Exploratory analyses tested differences within and between groups at each timepoint for percent WIC benefit redemption and diet quality of grocery purchases, evaluated using the Grocery Purchase Quality Index-2016 (GPQI-2016). Overall, quantitative study measures suggested that the intervention was feasible and that the personalized, modifiable pre-filled cart was acceptable. These findings were also supported during qualitative interviews, in which participants highlighted time-savings, flexibility, and WIC labels as facilitators of WIC online shopping. Exploratory results showed that mean percent redemption more than doubled for most WIC food categories (p<0.04) and that mean GPQI-2016 total and component scores moderately increased, albeit non-significantly.
These studies provide evidence that 1) low-income WIC-participating women who have nutritional risk factors have suboptimal diet quality comparable to income-eligible and income-ineligible pregnant and postpartum women with and without nutritional risk factors; suggesting that further attention is needed to address barriers to consuming a health-promoting diet among this vulnerable group; and that 2) a WIC-tailored, personalized pre-filled online shopping cart may be a promising tool to improve WIC benefit redemption and diet quality of grocery purchases among WIC-participating women. Given this evidence and its limitations, further interventions are needed to encourage health-promoting food choices among WIC participants in online grocery environments to ensure WIC's continued support for low-income women's health.
Recommended Citation
Melo Herrera, Yarisbel, "IMPROVING THE DIET QUALITY OF WIC-PARTICIPATING WOMEN USING DIGITAL FOOD ENVIRONMENTS" (2024). Open Access Dissertations. Paper 1651.
https://digitalcommons.uri.edu/oa_diss/1651