| The WHO is on a mission to make politicians understand that the climate crisis is a health crisis. Last year, in the blunt language of a doctor worn down by a stubborn patient, WHO director general Tedros Adhanom Ghebreyesus said subsidising and burning fossil fuels is “an act of self-sabotage”. Neira and her colleagues want to use the Cop28 summit in a few weeks to wake people up to the tremendous human cost of a global economy based around coal, oil and gas. She wants every politician and negotiator who delays action to walk away feeling the consequences. “Anytime you postpone – okay, are you ready to cope with that?” she asked when we met at a health conference in Berlin in October. “You have to live with that weight on your shoulders of the fact that you are at least not saving those lives – I don’t want to say killing – but at least not protecting the lives of those people.” That brings us back to our lungs. Burning fossil fuels kills millions of people each year, even before you factor in violent weather. I can’t tell you how much closer to death the dirt you breathe has brought you — some die from asthma triggered in childhood while others live as long as they otherwise would have — but on average, it shortens our lives more than almost everything else we fear. In 2019, air pollution was the fourth biggest risk factor for early death in the world. Only blood pressure, smoking and diet played more of a role — and we have some control over those through how much exercise we do, whether we smoke cigarettes, and what we eat. That makes air pollution a far bigger killer than extreme weather, which dominates discussions about climate change. But thankfully, for the most part, stopping climate change and cutting air pollution go hand in hand. The shift to clean energy means burning fewer fuels that spew toxic particles. If world leaders honour their promise to stop the planet heating 1.5C, and cut greenhouse gas pollution to net-zero by the middle of the century, the biggest benefit to our health will not be softened storms or weakened wildfires but the crisp, clean air that will fill our lungs. Doctors see “co-benefits” like this everywhere. Cleaning up transport means fewer vehicles, cleaner cars, and more walking and cycling — all of which can save 5 million lives a year, Neira told me. Cleaning up agriculture means a shift to healthier diets that can save millions more. Taken together, these health benefits make the case for fast climate action far stronger. And Neira is confident she can make policymakers see this too. Of course, doctors are well aware that knowing what a healthy life looks like is no guarantee that people will change their behaviour. If it were, my New Year’s resolutions of drinking less and working out more would not need to be renewed every 12 months. Read more on air pollution: | 