Digital interventions to improve plant-based eating: A systematic review and meta-analysis

Abstract Given the global use of digital media and their success in promoting unhealthy foods, there is growing interest in leveraging these platforms for dietary interventions. Yet, prior reviews show mixed results, underscoring the need to better understand which intervention components drive effectiveness. This systematic review evaluates the overall effectiveness of digital interventions in improving healthy, sustainable food intake (i.e. plant-based eating) and identifies which characteristics determine intervention effectiveness. We also explore differences in effectiveness across age and socioeconomic status (SES). A systematic search strategy was conducted across Web of Science, Embase and Scopus, complemented by forward and backward reference searching. Behaviour change techniques (BCTs) were coded using the Behaviour Change Taxonomy v1. A meta-analysis was conducted using robust variance estimation to account for effect size dependency across studies. Out of 9318 identified records, 46 were included in the review and 38 in the meta-analysis. Digital interventions had a small but significant positive effect on healthy, sustainable eating (d = 0.33, SE = 0.04, p < .001, 95% CI [0.25 - 0.42]). Subgroup analyses showed that interventions via social media or text messages were most effective. Social support emerged as the most promising BCT, and multiple effective interventions leveraged social norms. Both prevention- and promotion-focused strategies yielded significant effects. The strongest effects were observed among young adults. There was, however, limited research among adolescents and low SES individuals. This review provides evidence-based insights for public health practitioners designing digital dietary interventions. The effectiveness of digital interventions depends mainly on the digital platform and BCTs used, and varies by age group. More inclusive research targeting low SES populations is needed. Key messages • Digital interventions, particularly those using text messaging or social media platforms, can effectively promote healthy, sustainable eating, especially among young adults. • Incorporating social support or providing normative information in the intervention seems to generate the strongest effects.