The trial evidence is not in doubt: in adults with obesity, semaglutide and tirzepatide produce weight loss of a size previously seen only with surgery, and the SELECT trial showed a reduction in major cardiovascular events in people with obesity but without diabetes. What is still being established is what happens at population scale. Registry and claims studies from Denmark and the United States show uptake concentrated among people with diabetes, among the insured and the better off, and, in the US, high discontinuation within the first year. Real-world weight loss is smaller than in trials, partly because of dose and persistence. No national statistical series has yet shown a change in the incidence of diabetes or cardiovascular disease attributable to these drugs; the exposed population is still too small and too recent. The picture is moving quickly: oral formulations, price competition and widening eligibility are changing who takes them, and the countries with linked prescribing and outcome data — Denmark above all — will show the population effect first.