The utility of household Grocery Purchase Quality Index scores as an individual diet quality metric

Feasibility and acceptability of a personalized, pre-filled online grocery cart to improve benefit redemption and diet quality of grocery purchases among participants of the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC)

Most participants in the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) do not fully redeem their benefits due to barriers like transportation, confusing product eligibility, and unclear labeling. Online food shopping enables choice architecture to promote benefit redemption and maximize diet quality. We conducted a mixed-methods pilot randomized-controlled trial to assess the feasibility and acceptability of a pre-filled online grocery shopping cart to improve WIC benefit redemption and diet quality of grocery purchases. Rhode Island WIC participants (n = 24, mean age 29.4 ± 1.1 years, 75% Hispanic, 54% had never grocery shopped online) completed a baseline questionnaire and a simulated shopping episode (SSE), buying WIC and non-WIC items. After a week, we randomized participants into the intervention (personalized, modifiable carts pre-filled with 100% of the 2022 proposed WIC packages) or control (selected their items individually) groups before the second SSE. Both groups had WIC labels. We assessed feasibility using process data and percent agreement to feasibility questions, and acceptability via percent agreement to acceptability questions and post-intervention qualitative interviews. We conducted exploratory analyses to examine 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) scores. Quantitative study measures suggest that the intervention was feasible and that the personalized, modifiable pre-filled cart was acceptable. These findings were supported during qualitative interviews, where participants highlighted time-savings, flexibility, and WIC labels as facilitators of WIC online shopping. Exploratory results showed significant increases in mean percent redemption of most WIC food categories and non-significant moderate increases in most GPQI-2016 scores. These measures are vital for the future adaptation of a full-scale efficacy trial in real-life settings.

Sweetener Purchases in Chile before and after Implementing a Policy for Food Labeling, Marketing, and Sales in Schools

Background

Chile's landmark food labeling and advertising policy led to major reductions in sugar purchases. However, it is unclear whether this led to increases in the purchases of nonnutritive sweeteners (NNS).

Objectives

The objective of this study was to assess the changes in NNS and caloric-sweetened (CS) products purchased after the law's first phase.

Methods

Longitudinal data on food and beverage purchases from 2,381 households collected from January 1, 2015 to December 31, 2017, were linked to nutritional information and categorized into added sweetener groups (unsweetened, NNS-only, CS-only, or NNS with CS). Logistic random-effects models and fixed-effects models were used to compare the percentage of households purchasing products and the mean volume purchased by sweetener category to a counterfactual based on pre-regulation trends.

Results

Compared with the counterfactual, the percentage of households purchasing any NNS beverages (NNS-only or NNS with CS) increased by 4.2 percentage points (pp) (95% CI: 2.8, 5.7; P < 0.01). This increase was driven by households purchasing NNS-only beverages (12.1 pp, 95% CI: 10.0, 14.2; P < 0.01). The purchased volume of beverages with any NNS increased by 25.4 mL/person/d (95% CI: 20.1, 30.7; P < 0.01) or 26.5%. Relative to the counterfactual, there were declines of -5.9 pp in households purchasing CS-only beverages (95% CI: -7.0, -4.7; P < 0.01). Regarding the types of sweeteners purchased, we found significant increases in the amounts of sucralose, aspartame, acesulfame K, and steviol glycosides purchased from beverages. Among foods, differences were minimal.

Conclusions

The first phase of Chile's law was associated with an increase in the purchases of beverages containing NNS and decreases in beverages containing CS, but virtually no changes in foods.

Perspective: Novel Approaches to Evaluate Dietary Quality: Combining Methods to Enhance Measurement for Dietary Surveillance and Interventions

Refining existing dietary assessment methods to reduce measurement error and facilitate the routine evaluation of dietary quality is essential to inform health policy. Notable advancements in technology in the past decade have enhanced the precision and transformation of dietary assessment methods with applications toward both population health and precision nutrition. Within population health, innovative applications of big data including use of automatically collected food purchasing data, quantitative measurement of food environments, and novel, yet simplified dietary quality metrics provide important complementary data to traditional self-report methods. Precision nutrition is similarly advancing with greater use of validated biomarkers for assessing dietary patterns and understanding individual variability in metabolism. Concurrently enhancing our understanding of diet-disease relations at the population health and precision nutrition levels provides tremendous potential to generate evidence needed to advance public health nutrition policy. This commentary highlights the importance of these advances toward progressing the field of dietary assessment and discusses the application of food purchasing data, data analytics, alternative dietary quality metrics, and -omics technology in population and clinical medicine.