Health harms that discourage alcohol consumption: A randomized experiment of warning messages

•Health warnings about alcohol could discourage alcohol consumption.•Health warnings – regardless of topic – are perceived as more effective at discouraging alcohol consumption than control statements.•Among the 16 warning topics tested, liver disease, cancer, dementia, and hypertension were perceived as most effective.•None of these topics are included in the current US alcohol warning. Health warnings about alcohol consumption could inform consumers and discourage alcohol consumption, but little is known about what topics these warnings should address. We sought to identify promising topics for alcohol warnings. In January 2024, we recruited a convenience sample of 2,522 US adults ages ≥ 21 years. In an online within-subjects experiment, participants viewed messages about 6 topics (5 warning topics selected from a pool of 16 topics [e.g., liver disease, liver cancer] and 1 control topic [i.e., recycling or reselling products]) shown in random order. For each topic, participants viewed and rated 2 statements about that topic on perceived message effectiveness (primary outcome) and reactance (secondary outcome). The 16 warning topics elicited higher perceived message effectiveness than the control topic (ps