Cardiovascular disease, diabetes, chronic obstructive pulmonary disease, cancers, and other non-communicable diseases are among the leading causes of morbidity and mortality in low-income, middle-income, and high-income countries, and The Lancet Taskforce recently made the case for investing in non-communicable disease prevention. Now, in The Lancet Planetary Health, Benjamin Bowe and colleagues report that exposure to PM2·5 air pollution is indeed a risk factor for diabetes.