Life expectancy has increased worldwide, but it did not turn out to be unalloyed good news. That is because the time spent in poor health has grown. The gap widened especially in wealthier countries. In developed countries, better medical services extended life expectancy, but healthy life expectancy did not increase by as much.
On the 21st (local time), a team led by Christopher Murray, director of the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, published the 2023 Global Burden of Disease (GBD) findings in the international journal Lancet Public Health. The study measured the morbidity gap—the difference between life expectancy and healthy life expectancy—across 204 countries between 1990 and 2023.
◇ healthy life expectancy did not rise as much as life expectancy
According to the paper, the morbidity gap widened in almost all places during this period. It increased from 8.8 years in 1990 to 10.7 years in 2023. Globally, this means people are spending more time in poor health. On average, people spent 14.5% of their lives being ill, up from 13.6% in 1990.
The baseline metric for this study is life expectancy at birth. Between 1990 and 2023, life expectancy rose from 64.6 years to 73.8 years. At the same time, healthy life expectancy—years lived in good health without disease—also increased, from 55.9 years to 63.1 years, but it failed to keep pace with gains in life expectancy, leading to a steady rise in years lived with chronic illness and disability.
The researchers said the COVID-19 pandemic caused temporary changes but did not reverse the broader trend of a widening morbidity gap. Due to the pandemic, global life expectancy fell to 71.9 years in 2021 and healthy life expectancy to 61.7 years. The global average morbidity gap narrowed by 0.1 year, from 10.4 years in 2020 to 10.3 years in 2021. This was interpreted not as people suddenly becoming healthier, but as a result of life expectancy shrinking more sharply than healthy life expectancy.
Murray said, "These findings suggests that future health gains can be achieved not only by extending life but also by improving health," and added, "Progress in healthy aging should be measured not only by life expectancy but also by healthy life expectancy, and we should reduce the time spent in poor health by increasing investment in disease prevention, long-term disease management, and chronic disease treatment."
◇ the richer the country, the larger the morbidity gap
It is often assumed that high-income countries, with stronger medical infrastructure, live longer and healthier than low-income countries, but the reality differed. Where more medical benefits are available, more people live longer, but the burden of chronic disease has also increased. As of 2023, the morbidity gap was largest in the United States at 14 years, followed by Australia (13.9 years), Canada (13.7 years), New Zealand (13.1 years), and the Netherlands (12.9 years).
Korea's morbidity gap increased from 9.4 years in 1990 to 11.6 years in 2023, ranking 48th. As life expectancy rose faster than healthy life expectancy, the period living with disease or disability lengthened by 2.3 years over this time. That means the time spent in an unhealthy state increased accordingly.
By contrast, sub-Saharan Africa had the smallest morbidity gap at 9.0 years. This does not mean people there are healthier, but that shorter life expectancy reduces the time spent living with disease or disability. North Korea ranked 146th out of 204 countries in 2023, with a 9.4-year gap between life expectancy and healthy life expectancy.
By sex, women lived longer but spent more time in poor health. In 2023, women's average morbidity period was 12.1 years, longer than men's 9.3 years. This was true in both high-income and low-income countries. The researchers said this shows that although women outlive men, they also live longer with disease and disability regardless of the level of socioeconomic development.
A small number of chronic conditions accounted for the increase in time lived with disease. As of 2023, the researchers said chronic diseases made up 57.4% of the total time in deteriorated health. Musculoskeletal disorders—especially low back pain—were the largest drivers of the morbidity gap, followed by mental disorders such as depression and anxiety, sensory organ disorders including age-related hearing loss, and injuries such as falls.
The researchers said there are relatively straightforward ways to prevent the morbidity gap. Even without breakthrough treatments, changing lifestyle habits and focusing medical investment can address key factors. Globally, elevated fasting plasma glucose, high body mass index, child and maternal malnutrition, and smoking were identified as major risk factors contributing to the morbidity gap. Air pollution also ranked among the top five risk factors.
References
Lancet Public Health (2026), DOI: https://doi.org/10.1016/S2468-2667(26)00098-8