Unhealthy food marketing through prominent placement in Swedish online supermarkets

Background With online grocery sales rapidly increasing, the digital food retail environment has become an important determinant of dietary patterns. While marketing strategies are well-understood in physical supermarkets, evidence from online settings remains limited. We aimed to assess placement-based marketing strategies in Swedish online supermarkets. Methods Using a cross-sectional study design, we audited the two largest Swedish online supermarkets (Coop and ICA) between April and May 2024. Placement-based marketing strategies (ie, advertisements and site content, cross-promotions and recommendations and default product listings) were systematically assessed across key webpage sections (ie, homepage, category page, search results, product pages and checkout page) for each retailer across six locations in three major cities. Product healthiness was assessed using Nutri-Score, with prevalence of Health Star Rating and Nordic Keyhole also reported. Descriptive statistics and χ 2 tests were used to examine differences by retailer and area-level Socioeconomic Index. Results Of 14 099 eligible promoted products, 65.5% were classified as unhealthy by Nutri-Score and 44.8% by Health Star Rating. Only 9.9% displayed the Nordic Keyhole, with an additional 6.5% being qualifying raw produce. Cross-promotions and recommendations (50.6%) and default listings (41.2%) were the most common strategies, both dominated by unhealthy products. Homepages displayed the greatest number of promoted products (mean 78.3). Coop displayed substantially more promotions than ICA, but the proportion of unhealthy products was similar between retailers (p=0.071). No significant differences were observed between areas of high and low Socioeconomic Index (p=0.373). Conclusions Swedish online supermarkets disproportionately promote unhealthy products through placement-based marketing strategies. Given the influence of site design on shopping behaviour—especially relevant in the online setting—and broad public support for regulation, these results highlight the potential for policy action to improve the digital retail food environment, support healthier diets and lower risks of diet-related disease.