Most lists of global health dangers are really lists of what is already killing people. A new Lancet Commission, launched on October 11 at the World Health Summit in Berlin, tried something different. It asked which threats could wipe out the most years of healthy life between 2025 and 2100, then ran a best case and a worst case for each. The answer was 17 threats, two of which it says carry extinction potential.

The rule that decided the list

The Commission screened hundreds of candidate threats using risk analysis covering 204 countries and territories from the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, according to The Lancet's release. To make the list, a threat had to meet three tests. It could account for at least one billion disability-adjusted life years (DALYs) by 2100, there had to be enough data to model it, and there had to be real scope for policy action.

That last test shapes everything. The Commission looked at the gap between a plausible best and worst future for each threat, a figure it calls amenable DALYs, meaning the years of good health that targeted action could save. The headline is therefore not how bad each threat is in absolute terms. It is how much a decision-maker can still change.

The two threats with extinction potential are the malicious use of artificial intelligence and nuclear conflict. Their probability is low, the Commission says, but their consequences are so severe that it treats them as urgent. The other 15 are air pollution, antimicrobial resistance, childhood malnutrition, climate change, conventional conflict, declining development assistance for health, high alcohol use, high blood pressure, income inequality, low educational attainment, naturally occurring pandemics, obesity, poor mental health, smoking and unhealthy ageing.

What the list leaves out

Notice what is missing. Ischemic heart disease and several cancers did not make the final 17, because the Commission judged they already receive substantial policy attention and spending, according to the project's methodology page. That is a defensible choice for a document about neglected risk. It is also a reminder that the list is not a ranking of what will cause the most deaths. A reader who takes it as a count of tomorrow's leading killers will get it wrong.

The Lancet's own editorial makes the same point. It says the Commission does not present a fixed ranking of threats or policy priorities and that its findings will probably change as new evidence arrives.

The numbers that do not match the headlines

Some of the quantified figures cut against intuition. Obesity is forecast to contribute 23.1 billion potential DALYs by 2100 that policies could avoid. Low educational attainment accounts for 16.1 billion, with women and children in sub-Saharan Africa facing the greatest burden. Income inequality accounts for 13.8 billion, which the Commission equates to 25 COVID-19 pandemics. Malicious AI is put at 10.4 billion, and acting on nuclear conflict could avert an estimated 133 million deaths and 9.35 billion DALYs.

Climate change looks small beside them. Limiting warming to about 1.8°C rather than 4.4°C would prevent 1.89 billion years of healthy life lost to causes such as extreme heat and air pollution. But the Commission warns that the true burden is likely greater, since the estimate captures only direct harms that can be measured today and excludes displacement, drought and mental health effects.

This is the catch in any common metric. Threats that are easy to model, like obesity or education, produce big, tidy numbers. Threats that act through chains of events, like climate, can look smaller than they are. Read the numbers as a map of where measurement is strongest, not as a verdict on which problem matters most. The Commission's guidance on obesity also lands as a policy question. Our look at WHO's first child obesity guidelines shows how much of the response still depends on evidence that is limited.

The threat that is already unfolding

Not every item is a forecast. The Commission estimates that sub-Saharan Africa would bear around 70 percent of the amenable health burden linked to a collapse in development assistance for health. That is a threat of present policy decisions, not future technology.

Pandemics sit on the same list. This week's reminder of how that plays out in practice is Kenya's first imported Ebola case, where a sick man crossed three borders before anyone had a laboratory result. A health system built to spot one pathogen at a time is the opposite of what the Commission is proposing.

What it asks leaders to do

The Commission's agenda has three parts. First, build readiness, meaning threat-ready health systems with dedicated teams for foresight, prevention and preparedness, funded durably rather than through ad hoc crisis responses. Second, back breakthroughs, with more investment where tools are inadequate, including vaccines, antibiotics, obesity treatments and climate technologies. Third, track threats, through regular independent reassessment and a proposed Lancet Monitor of 21st Century Global Threats to Health.

Co-chair Christopher Murray said the striking finding is that humanity still has the agency to act. The other co-chair, Natalia Kanem, former head of the UN Population Fund, called for embedding foresight into decision-making.

The proposal is aimed beyond health ministries. The Lancet says it addresses leaders in finance, defence, climate and security, and that is the part to watch. A framework only matters if a treasury or a defence ministry uses it. The first sign will be whether the Monitor gets funded, and whether anyone outside health reads it.

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