Digital tools for food system challenges: A systematic review of their impact on food waste and sustainable practices

<ns3:p> This systematic review investigates how digital tools mitigate food waste and support more sustainable consumption and supply-chain practices. We searched Web of Science, Scopus, and Google Scholar, and complemented scholarly records with scans of the Apple App Store and Google Play and targeted queries of European retailer websites to capture live consumer-facing features (search window: 31 July 2023–15 June 2024). Screening followed PRISMA 2020 using PICOS criteria; data were extracted into a standardized template and appraised with the Mixed Methods Appraisal Tool (MMAT) for empirical studies and the AACODS checklist for grey literature. Given substantial heterogeneity in interventions, outcomes and reporting units, we conducted a structured narrative synthesis. We included 201 eligible tools, ranging from mobile apps and online platforms to retailer websites, gamified experiences and data storytelling solutions. Across categories, many evaluations reported reductions in food waste or shifts towards lower-impact purchases, but study designs were often small-scale, with short follow-up and inconsistent metrics; transparent CO₂e accounting was the exception rather than the rule. Retailer nudges and labels appear promising for scalable impact when embedded as defaults and supported by credible data; games and gamified apps show strong engagement potential yet limited real-world behavioural evidence; and data storytelling improves comprehension but rarely measures downstream actions. Within the Horizon Europe CHOICE project, we highlight design patterns, reporting gaps and priorities for future trials that can inform behaviour-oriented mitigation pathways (standardised outcome metrics, longer time horizons and co-design with retailers and users). The curated catalogue of tools is openly available on Zenodo (DOI: <ns3:ext-link xmlns:ns4="http://www.w3.org/1999/xlink" ext-link-type="uri" ns4:href="http://dx.doi.org/10.5281/zenodo.12742264">10.5281/zenodo.12742264</ns3:ext-link> ). </ns3:p>