Federal health and safety officials warned consumers away from cantaloupes in 2011 and again in 2012. The warnings occurred under similar market conditions but were for contamination by two different foodborne microorganisms that posed entirely different health risks. This unhappy natural experiment allows us to investigate whether consumers make food choices that account for the severity of pathogens and the associated health risks. A retail demand system for U.S. melons is estimated to account for ordinary price- and income-induced changes in demand. Remaining changes are attributed to warnings. After consumers were informed about the risk with the higher fatality rate, the demand for cantaloupes fell and consumers substituted other melons. No such shifts in demand were evident under the lower fatality risk, despite more illnesses attributed to it.