Humanity is living longer than ever before, yet a troubling surge in deaths among adolescents and young adults is reshaping global health priorities, according to new research published in The Lancet by the University of Washington’s Institute for Health Metrics and Evaluation (IHME).
In 2023, life expectancy climbed back to pre-pandemic levels, reaching 76.3 years for women and 71.5 years for men. That represents an impressive 20-year increase compared to 1950, with all 204 countries studied showing declines in mortality rates. But the overall improvement masks widening inequalities — and an “emerging crisis” in young populations.
The data reveals that Covid-19 has fallen from the top global killer in 2021 to 20th place in 2023, with heart disease and stroke resuming their position as the world’s leading causes of death. Deaths from measles, diarrheal diseases, and tuberculosis have sharply declined, signaling a continued shift from infectious diseases to chronic, noncommunicable illnesses.
However, deaths from diabetes, chronic kidney disease, and Alzheimer’s have increased, driven largely by aging populations and lifestyle factors such as obesity and high blood sugar. About half of the world’s disease burden is considered preventable, the study notes, linked to modifiable risks including high blood pressure, smoking, high cholesterol, and environmental pollution.
While global populations are aging, death rates among teenagers and young adults are climbing in several regions, reversing decades of progress. Among people aged 20 to 39 in high-income North America, deaths have surged due to suicide, drug overdoses, and alcohol abuse. Similar increases were seen among children aged 5 to 19 in Eastern Europe, the Caribbean, and parts of sub-Saharan Africa, often driven by infectious diseases and unintentional injuries.
“These findings are a wake-up call,” said Dr. Christopher Murray, IHME Director. “Governments and health systems must urgently respond to the disturbing trends reshaping public health needs.”
The gap between the healthiest and least healthy regions remains stark. Life expectancy ranges from over 83 years in high-income countries to just 62 years in sub-Saharan Africa, underscoring persistent inequalities. Experts warn that cuts to global health aid threaten to widen this divide, as many low-income nations rely on external funding for essential primary care and vaccines.
Mental health is also emerging as a significant factor. Burdens from anxiety and depression have surged, contributing to mortality and disability worldwide.
Researchers are urging policymakers to expand their focus beyond traditional child mortality and infectious diseases to address rising risks among adolescents and young adults. Without targeted action, the gains of recent decades could be undone.