Impact of physical activity and diet in health-adjusted life expectancy: A PAF approach

Abstract Background According to WHO, physical inactivity and unhealthy diet are major risk factors for NCDs globally. GBD studies established causal relationships between these factors and major ncds cancer, heart disease, and diabetes. Despite known benefits, 90% of Korean adolescents and 45% of adults don't meet recommended physical activity levels, with fruit/vegetable consumption below WHO recommendations. Health-adjusted life expectancy (HALE) reflects healthy living duration and is Health Plan 2030's goal in Korea, but factors affecting it need quantification. Objectives To quantify physical activity and diet impacts on HALE using Population Attributable Fraction approach and simulate improvements’ effects. Methods Using National Health Insurance Service data, we calculated PAFs for physical activity and fruit intake on major diseases. We employed Sullivan's Methods to simulate life expectancy and HALE changes with risk factor improvements. Results Improved physical activity increased life expectancy by 0.031 years but HALE by 0.769 years. Largest HALE gains were in ischemic heart disease (0.981 years) and ischemic stroke (0.978 years). Males showed greater life expectancy increases; females showed greater HALE increases. Improved fruit intake increased life expectancy by 1.942 years and HALE by 3.293 years. Largest HALE gains were in esophageal cancer (3.360 years), ischemic stroke (2.042 years), type 2 diabetes (1.853 years), and ischemic heart disease (1.720 years). Both risk factors increased HALE more than life expectancy, suggesting greater impact on reducing disability than mortality. Conclusions Physical activity and nutrition improvements extend HALE more than life expectancy, with fruit intake showing greater effect. These findings highlight the importance of promoting physical activity and nutrition for ‘healthy living’ rather than just extending lifespan. Results provide foundational data for evidence-based policy development. Key messages • Improving physical activity and diet extends healthy life. Both factors improves disability more than mortality, supporting health promotion policies focused on quality of life. • Utilisation of PAF help us understanding how HALE changes with intervention on behavioral risk factors.