The Impact of Personalised Weight Feedback on Heart Attack Incidence: A Regression Discontinuity Approach

This study investigates whether providing individuals with feedback about their weight status influences long-term health outcomes, specifically the incidence of myocardial infarction (heart attack) over a 13–19 year period. Using data from the UK Biobank, where participants received weight status feedback based on Body Mass Index (BMI) thresholds, the study employs a regression discontinuity design to estimate the causal impact of receiving adverse weight information. The findings reveal that such feedback reduces the risk of myocardial infarction by 0.6 percentage points, representing an approximate 18% relative risk reduction. While the magnitude of the effect is modest, the low cost and scalability of information-based interventions suggest a potential value in preventative healthcare. These results contribute to the literature by linking personalised health information not just to behavioural change, but to tangible long-term health outcomes. The study supports the integration of weight feedback into routine screening programmes as a cost-effective strategy to mitigate heart attack risk and improve population health as part of preventative health policy. • Uses a regression discontinuity design exploiting BMI-based weight-status feedback • Shows adverse weight information reduces myocardial infarction risk by 0.6 p.p. • Estimated effect equals an ~18% relative reduction in long-term heart attack incidence • Demonstrates that personalised health feedback can yield durable health benefits • Suggests integrating weight feedback into routine screening as a low-cost prevention tool