Can we improve the healthiness of online food purchases through the Nutri-Score and site design?

To encourage healthier food choices, several European countries have adopted the Nutri-Score front-of-pack label. This voluntary label was designed for products on display within supermarkets. Despite the digital transition, the impact of Nutri-Score in an online environment remains under-researched. This study assesses the impact of three Nutri-Score interventions on online food purchasing. Belgian participants (N = 1151) shopped for groceries in a purpose-built Virtual Online Supermarket with a prescribed shopping list. Participants were randomly assigned to one of seven conditions comprising up to three interventions: Nutri-Score presence (no/yes), default product sorting by Nutri-Score (yes/no), and the options to filter and sort by Nutri-Score (no/yes). The outcomes of interest were mean UK Food Standards Agency nutrient profiling system diet score and the percentage of and expenditure on food items with Nutri-Score A, B, C, D, and E. Compared to the control group, the mere presence of Nutri-Scores did not affect the outcomes of interest. Changing the default sorting from alphabetically to by healthiness improved the mean diet score, increased the purchase of items with Nutri-Scores A and B, and reduced the purchase of items with Nutri-Scores D and E. In contrast, when present, the user-driven options to filter and sort the products by healthiness were barely used (<10 %), and this intervention didn’t change purchases. In sum, changing the default sorting of products so that healthier products appear first may encourage consumers to buy healthier.