King's College London

Researchers from King’s College London have contributed to a major international study revealing that healthy lifestyle choices can significantly reduce disability among older adults in South Korea and China. However, the benefits are not equally distributed across income, education, and geography.

The study analysed data from over 11,000 older adults across two nationally representative cohort studies - the Korean Longitudinal Study of Aging (KLoSA) and the Chinese Longitudinal Healthy Longevity Survey (CLHLS) - spanning a decade from 2008 to 2018.

The research team, which includes scholars from King’s, Peking University, Zhejiang University, and Tongji Medical College, examined the impact of four modifiable lifestyle factors: non-smoking, non-drinking, regular physical activity, and weekly social contact.

Their findings show that each additional healthy lifestyle factor was associated with a 0.14–0.24 point reduction in disability scores, measured through limitations in activities of daily living.

However, the study uncovered significant inequalities.

Older adults with higher incomes experienced greater reductions in disability, likely due to better access to health resources and supportive environments.

Interestingly, those with lower education levels saw more pronounced benefits from lifestyle changes, which the authors attribute to the “marginal effects” of improvement - suggesting that individuals starting from a less healthy baseline may gain more from adopting healthier habits.

Urban residents also fared better than their rural counterparts, reflecting disparities in access to healthcare, fitness facilities, and health education.

Published in the American Journal of Epidemiology, the study highlights that rural populations often face structural barriers that limit their ability to maintain healthy lifestyles, despite willingness or awareness.

Lead author Dr Chengxu Long, based in the Department of Global Health and Social Medicine at King’s, said:

“Our findings suggest that promoting healthy lifestyles among less-educated and rural older adults could yield substantial health benefits and help reduce inequality. Public health strategies must be tailored to address these disparities.”

The authors call for dual policy approaches - combining poverty alleviation with targeted health literacy campaigns - to ensure that vulnerable groups can adopt and sustain healthy behaviours. Recommendations include subsidised exercise programmes, mobile health clinics for rural areas, and simplified health education tailored to older adults with limited formal schooling.

As both South Korea and China face rapidly ageing populations, the study offers timely insights for policymakers across Asia and beyond. It underscores the importance of addressing social determinants of health to ensure that the benefits of healthy ageing are accessible to all.

Read the paper:

Chengxu Long, Yao Yao, Dongfeng Tang, Yichao Li, Fangfei Chen, Yinghua Xie, Shangfeng Tang, Inequalities in the association Between lifestyles and disability: prospective cohort studies in South Korea and China, American Journal of Epidemiology, 2025 https://doi.org/10.1093/aje/kwaf177