Study: Family grocery purchases improved when online grocery carts were preloaded with healthy ingredients

BUFFALO, N.Y. — University at Buffalo researchers have shown that preloading Instacart online grocery carts with healthy ingredients could be a useful tool for improving the diets of families with young kids at risk for obesity.

Published on December 3 in Appetite, the randomized, controlled pilot study found that providing families with healthy recipes and then preloading online grocery carts via Instacart with the ingredients needed to make those recipes resulted in families making purchases that were significantly more nutritious compared to a group that received only the recipes. Families paid for their grocery purchases as usual and were free to switch out pre-loaded cart ingredients if they wanted to.

“The findings support the idea that healthier choices can be supported by making them easier and more automatic,” says Stephanie Anzman-Frasca, PhD, corresponding author on the paper and an associate professor of pediatrics and director of the Child Health and  Behavior Lab in the Jacobs School of Medicine and Biomedical Sciences at UB.

PHOTO: https://www.buffalo.edu/news/releases/2025/12/UB-Instacart-study-family-nutrition-default.html

Research shows that children who are overweight by age 5 are more likely to have obesity later in life, putting them at risk for cardiovascular and other diet-related diseases.

“Since experience with foods and flavors early in life can influence children’s later food preferences, eating behavior and health, it’s important to make healthy choices easier for families with young children,” Anzman-Frasca says.

A ‘real-world’ family shopping intervention

The study was the first time that a default grocery shopping intervention for families with young children was conducted in a real-world scenario, where families were purchasing the actual groceries they would be eating during the four-week study. The goal was to test in a real-world shopping situation the impact of “optimal defaults,” the idea that preselected options can be helpful in guiding people toward healthy behaviors.

Anzman-Frasca and her colleagues in the Division of Behavioral Medicine have done pioneering work in behavioral medicine and nutrition, including prior research on optimal defaults; in this study, they wanted to see how the preloaded default grocery carts would work in families with young children at risk for obesity.

Eligible families had to do at least 75% of their grocery shopping online, and one parent had to have a body mass index of at least 25, classifying them as overweight. A diverse group of 69 families, nearly half of whom were living with lower incomes, participated.

All families received healthy recipes for two weeks, and a sample recipe bundle is included in the published paper. Each weekly bundle included recipes for three dinners, plus a “bonus” recipe, such as a snack, that used leftover ingredients from the dinner meals. While all participating families received the recipes, half of the families had their Instacart online grocery carts preloaded with the ingredients to make those dishes, while the other half did not.

“When faced with making a choice, most people will take the default option unless they’re highly motivated to choose an alternative,” says Mackenzie Ferrante, PhD, a co-author and assistant professor at Rutgers University, who did postdoctoral work at UB. “These days, the easy, or default, choice with food is rarely the healthy option. We wanted to see what would happen if the default option for families was the healthy choice.”

“This real-world study shows how Instacart’s technology can make it easier for families to fill their tables with healthier foods,” says Beatrice Abiero, PhD, senior manager of policy research at Instacart. “By examining how our platform can inspire more nutritious choices, we’re seeing how online grocery can support healthier habits — without adding cost — at scale. We’ll continue to use Instacart Health tools to support research and nutrition programs that help make the healthy choice the easy choice.”

The researchers note that children between the ages of 2 and 5 are frequently afraid of, and resistant to, trying new foods, which can pose a challenge. In this study, recipes were selected for families based on information that they provided about their family’s food preferences at the beginning of the study. Results showed that there was a significantly greater improvement in nutritional quality of families’ grocery purchases in the group that received the preloaded carts compared to the group receiving only the recipes.

‘Eye-opening’ to see what they were spending

Across both groups, families’ spending on groceries decreased over the course of the study. While this wasn’t a main goal of the study, and more research needs to be done, the researchers say it’s possible that the requirement to fill out forms about what they purchased might have made families more aware of superfluous items they were buying. Some participants noted it was eye-opening to see how much they were spending.

In the future, the researchers want to extend the work to examine how the preloaded online grocery carts affect family grocery purchases over a longer time period and corresponding impacts on dietary intake and health. In the meantime, Anzman-Frasca says, families can use the “Buy It Again” feature on Instacart to repurchase healthy ingredients they have enjoyed in the past, which can be used to easily reload those ingredients into future shopping carts.

When this study began in 2023, the White House cited it as an example of how to combat nutrition insecurity and diet-related disease. The project was supported by Instacart and leveraged Instacart Health tools. The support from Instacart complemented an initial investment from the UB Office of the Vice President for Research and Economic Development. UB’s Clinical and Translational Science Institute provided seed funding for prior pilot research that set the stage for the current project.

Additional co-authors include Juliana Goldsmith, Adrianna Calabro, Karlie Gambino and Leonard H. Epstein, PhD, of the Jacobs School; Lucia A. Leone, PhD, and Gregory E. Wilding, PhD, of the UB School of Public Health and Health Professions; and Brianna Wallenhorst of the Independent Health Foundation.