Promoting healthy dietary intake among families with obesity via a grocery shopping intervention - PROJECT SUMMARY Obesity is a diet-related disease that continues to be a major public health concern. Children who are overweight by age 5 are at increased risk for future obesity, highlighting the importance of early efforts to promote healthy diets. Modifying home food availability can impact the diets of children and their families, and online grocery shopping offers untapped potential as a way to modify the family food environment. The objective of this grant is to test a new family-based approach to early obesity prevention, specifically using optimal defaults to promote healthier online grocery shopping. Making “optimal” choices easier by making them the default option has strong scientific support, but this strategy has not been implemented in the context of online grocery shopping on a large scale. The study team’s preliminary research demonstrated the potential of pre-filling online grocery shopping carts with nutritious foods: this default grocery cart strategy had significant, positive effects on the nutritional quality of grocery purchases in two pilot studies. The proposed study will expand upon this preliminary research, recruiting 192 parents with obesity who use online grocery shopping and have a 2-to-5-year-old child. Families will be randomly assigned to a default grocery cart intervention or control group. Both groups will be provided with 4 main meal recipes and 4 lunch and/or snack recipes each week of a 6-month intervention period, with recipes corresponding to the Traffic Light Diet, an evidence-based diet for family-based obesity prevention and treatment. Corresponding nutritional guidance will be provided, with a goal to increase low energy-dense, high nutrient-dense foods and decrease the energy density of the diet. In addition, the defaults group’s online grocery carts will be pre-filled with items that correspond to the provided recipes each week. Participants can alter these carts as they like. Assessments will occur via grocery receipt forms, phone interviews, remote food photography, height/weight measurements, and online surveys. It is hypothesized that the defaults group will have household grocery purchases that are better-aligned with dietary goals (e.g., more fruits and vegetables, higher nutritional quality, fewer calories) (Aim 1), and that participating parents and 2-to-5-year-old children will have healthier dietary intake (e.g., more fruits and vegetables, higher nutritional quality, fewer calories) than controls (Aim 2) following the 6-month intervention. Effects on parent and child weight outcomes (Aim 3), as well as grocery spending, intervention implementation, and effect moderators will also be examined. These aims are designed to leverage a simple but powerful behavioral principle, optimal defaults, to make purchasing of healthier foods easier among families with young children during a period of the life span in which dietary preferences and future weight trajectories are being established. In the long-term, this research offers the potential for a scalable, sustainable approach to facilitate healthier dietary intake among a broad population of individuals and families at risk for diet-related diseases.
