To examine the feasibility and implementation of an optimal defaults intervention designed to align grocery purchases with a diet recommended for people with or at-risk for type 2 diabetes.

This was a 5-week pilot randomised trial with three groups: in-person grocery shopping, shopping online and shopping online with ‘default’ carts. Participants were asked to shop normally in Week One, according to group assignment in Weeks Two–Four (intervention period), and as preferred in Week Five. All groups received diabetes-friendly recipes via email each intervention week.

Participants grocery shopped in person or online. Grocery receipt forms, enrolment information and exit surveys were collected remotely and used to assess feasibility and implementation.

Sixty-five adults with or at-risk for type 2 diabetes.

Sixty-two participants completed the exit survey and fifty-five submitted receipts all 5 weeks. Forty utilised recipes, 95 % of whom indicated recipes were somewhat or very useful. Orange chicken, quesadillas and pork with potato and apples were the most liked recipes. Most Defaults group participants accepted at least some default cart items. Recipes with the highest default acceptance were whole grain pasta and chicken, quesadillas with black beans and chicken with olives. Participants’ primary concerns about the intervention were costs associated with online shopping, inability to select preferred foods and some recipes including ingredients household members would not eat.

The study had high retention, data were successfully collected remotely and the intervention was acceptable to most participants. Tailoring recipes to household preferences may be beneficial in future studies.

The goal of the present study was to apply experimental economic methods in an online supermarket to examine the effects of nutrient profiling, and differential pricing based on the nutrient profile, on the overall diet quality, energy and macronutrients of the foods purchased, and diet cost.

Participants were provided nutrient profiling scores or price adjustments based on nutrient profile scores while completing a hypothetical grocery shopping task. Prices of foods in the top 20 % of nutrient profiling scores were reduced (subsidized) by 25 % while those in the bottom 20 % of scores were increased (taxed) by 25 %. We evaluated the independent and interactive effects of nutrient profiling or price adjustments on overall diet quality of foods purchased as assessed by the NuVal® score, energy and macronutrients purchased and diet cost in a 2×2 factorial design.

A large (>10 000 food items) online experimental supermarket in the USA.

Seven hundred and eighty-one women.

Providing nutrient profiling scores improved overall diet quality of foods purchased. Price changes were associated with an increase in protein purchased, an increase in energy cost, and reduced carbohydrate and protein costs. Price changes and nutrient profiling combined were associated with no unique benefits beyond price changes or nutrient profiling alone.

Providing nutrient profile score increased overall NuVal® score without a reduction in energy purchased. Combining nutrient profiling and price changes did not show an overall benefit to diet quality and may be less useful than nutrient profiling alone to consumers who want to increase overall diet quality of foods purchased.