From AI and nuclear war to obesity, Lancet flags 17 threats to humanity in the 21st century

A new Lancet Commission maps 17 interconnected threats that could cost future generations tens of billions of years of healthy life by 2100, urging governments to treat health risks as economic, environmental and national security challenges.

In Short

• The report links climate, pollution and conflict to compound health risks
• Malicious AI use and nuclear war are flagged as extinction-level dangers
• Keeping warming near 1.8°C could save billions of healthy life-years

The next global health catastrophe may not come from a single pandemic. It could emerge from the combined effects of air pollution, climate change, obesity, antimicrobial resistance, inequality and conflict, with artificial intelligence (AI) and nuclear war carrying the potential to threaten human survival itself.

A new Lancet Commission on 21st Century Global Threats to Health, launched at the World Health Summit 2026 in Berlin, identifies 17 interconnected threats that could cause catastrophic health losses between 2025 and 2100.

Drawing on historical evidence and risk modelling across 204 countries and territories by the Institute for Health Metrics and Evaluation (IHME), the Commission argues that decisions taken today will determine how much preventable illness, disability and premature death future generations face.

The assessment moves beyond the conventional approach of treating health threats as separate problems. It examines how risks interact, and how policy decisions across healthcare, finance, education, climate, defence and technology could change their long-term consequences.

The Commission classifies a threat as catastrophic if it could account for at least one billion disability-adjusted life years (DALYs) by 2100, can be modelled using available data, and offers sufficient scope for policy intervention.

DALYs measure healthy years lost to illness, disability or premature death.

AI, NUCLEAR RISKS

The report identifies the malicious use of artificial intelligence and nuclear conflict as two threats with extinction potential. Although their likelihood remains low, their possible consequences are sufficiently severe to warrant preventive action.

According to the Commission's estimates, measures to prevent nuclear conflict could avert 133 million deaths and 9.35 billion DALYs by 2100. Reducing the risk of malicious AI use could avert another 10.4 billion DALYs.

Climate change presents a more immediate and already measurable threat. Limiting global warming to around 1.8°C, rather than allowing it to reach 4.4°C, could prevent an estimated 1.89 billion years of healthy life from being lost to direct effects such as extreme heat and air pollution.

The Commission cautions that the estimate excludes several difficult-to-measure consequences, including displacement, drought and mental health impacts.

Other threats include antimicrobial resistance, naturally occurring pandemics, childhood malnutrition, high alcohol consumption, high blood pressure, smoking, poor mental health, unhealthy ageing, low educational attainment, income inequality, declining development assistance for health and obesity.

The potential health losses associated with these risks are substantial. The Commission estimates that improving educational attainment could avert 16.1 billion DALYs, while reducing the health consequences of income inequality could avert 13.8 billion DALYs. Policies to reduce obesity risk could prevent 23.1 billion DALYs by 2100.

These are modelled estimates of potentially avoidable health loss, not predictions that all these years will necessarily be lost. Their purpose is to illustrate the difference policy intervention could make.

WARNING SIGNS FOR INDIA

In the case of India, the findings bring together several existing public health challenges that are often addressed through separate policy responses.

Air pollution and climate change are closely linked threats. Extreme heat, deteriorating air quality and changing environmental conditions can increase health risks, while placing additional pressure on hospitals and public health services.

The country’s large population and uneven access to healthcare also make preparedness and adaptation important.

Antimicrobial resistance (AMR), when atibiotics and other medicines designed to treat infections caused by common pathogens, is another major concern. Inappropriate antibiotic use, gaps in infection prevention and control, and the spread of drug-resistant infections can make routine illnesses harder to treat.

The Commission's framing reinforces why antibiotic stewardship, surveillance and access to effective treatment must be treated as connected priorities.

The report's emphasis on obesity and high blood pressure is also particularly relevant as India faces a growing burden of non-communicable diseases. These conditions increase the risk of cardiovascular disease, diabetes and other complications, creating long-term demands on households and the health system. Smoking and harmful alcohol use add to the burden.

The focus on childhood malnutrition alongside obesity also reflects the need to address India's double burden of malnutrition. Undernutrition and deficiencies can coexist with rising overweight and obesity, including within the same communities and households. Interventions must therefore improve nutrition quality and access rather than focus on weight alone.

Income inequality and educational attainment have implications beyond social policy. They influence people's ability to access healthcare, understand health information, adopt preventive measures and seek timely treatment.

The Commission also warns that people in resource-limited settings and marginalised communities are likely to bear a disproportionate share of the health losses.

The Commission has called for three broad responses: building health systems prepared for major threats, accelerating investment in breakthrough innovation, and strengthening surveillance of emerging risks.

Its co-chair, Christopher JL Murray, director, Institute of Health Metrics and Evaluation IHME at the University of Washington, said in a statement the central finding was that humanity still had the ability to act. Delaying action, he warned, would shift costs into the future and increase them.

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