Effect of Brief Produce Exposure and Unconstrained Grocery Gift Cards on Caregiver Influence on Diet of Elementary Age Children: A Randomized Clinical Trial

Abstract

Importance: Children's diets affect health trajectories but are difficult to influence, especially for resource-constrained families.

Objective: To assess the effectiveness of providing 4 weeks of grocery gift cards and small produce boxes to caregivers on their ability to support healthy shifts in children's diets.

Design, setting, and participants: This 2-group randomized clinical trial was conducted from May to July 2021, with 4 weeks of intervention and follow-up at 8 weeks. Resources were provided curbside at 3 schools, 3 housing sites, and 1 after-school site for use at home. Participants consisted of 1 index child ages 5 to 11 years with 1 index caregiver from 68 low-income families. Data were analyzed from July 2021 through March 2022.

Interventions: During each week for 4 weeks, caregivers were offered 10-lb (4.5 kg) boxes of fruits and vegetables, $10.00 grocery gift cards, an additional $10.00 gift card over the last 3 weeks triggered by a task completion, and a 1-time choice of a $25.00 food preparation tool.

Main outcomes and measures: Index child and caregiver diets were measured together over the phone at baseline, 4 weeks, and 8 weeks using the 2019 to 2020 Texas School Physical Activity and Nutrition (SPAN) tool, which measures the number of times food items were eaten over the prior day to report a SPAN Healthy Eating Index (SHEI) score and subscores for specific categories of foods (range, 0-57, with higher scores indicating a more healthful diet).

Results: Among 68 children (mean [SD] age, 8.2 [1.7] years; 35 [51.5%] girls) and caregivers (mean [SD] age, 37.9 [7.9] years; 63 mothers [92.6%]) from primarily low-income families, 26 caregivers were Hispanic or Latino (38.2%), while 18 caregivers were Black (26.4%), 25 caregivers were White (36.7%), and 24 caregivers had more than 1 race (35.3%). Most families were below the federal poverty level (41 of 60 families that reported income [68.3%]). Per participating caregiver, a mean (SD) 2.7 [1.4] fruit and vegetable boxes and $42.35 ($25.46) worth of gift cards were picked up over 4 weeks. Mean (SE) child SPAN SHEI increased from 32.03 (0.62) times/d to 33.75 (0.69) times/d at 4 weeks (ie, postintervention) and 34.03 (0.69) times/d 4 weeks later (ie, at 8 weeks of follow-up). Mean (SE) child fruit and vegetable intake increased from 5.31 (0.47) times/d to 5.78 (0.51) times/d postintervention and 6.03 (0.51) times/d at follow-up. Children in the control group did not have improved diet (overall mean [SE] SHEI: 31.48 [0.58] times/d at baseline, 31.68 [0.54] times/d postintervention, and 31.81 [0.52] times/d at follow-up; mean [SE] fruit and vegetable intake: 5.21 [0.45] times/d at baseline, 4.77 [0.45] times/d postintervention, and 4.68 [0.41] times/d at follow-up). Compared with children in the control group, mean SHEI was increased for children in the intervention group by 2.07 times/d postintervention and 2.23 times/d at follow-up. Improvements as a function of program dose were statistically significant for child SHEI (P = .01) and fruit and vegetable intake (P = .03). No significant changes in caregiver diets were found.

Conclusions and relevance: This study found that easily accessed fruits and vegetables and unconstrained grocery store cards provided directly to caregivers over 4 weeks resulted in improvements in child diet, which were sustained over 4 additional weeks. Future work may investigate whether diet improvement from a brief intervention optimized for caregiver flexibility reflects a natural maximum or potential for greater improvements on extension.

Trial registration: ClinicalTrials.gov Identifier: NCT04827654.

Figure 1.. Study Flowchart

Figure 2.. Child Texas School Physical Activity and Nutrition (SPAN) Healthy Eating Index (SHEI) Score Over Time

Means and SEs are presented.