BACKGROUND: Health messages alerting the public to previously unknown genetic risk factors for multifactorial diseases are a potentially useful strategy to create public awareness, and may be an important first step in promoting public health. However, there is a lack of evidence-based insight into its impact on individuals who were unaware of the existence of genetic risk factors at the moment of information exposure. METHOD: The authors conducted 3 experimental studies with health messages communicating information about genetic risk factors for salt sensitivity (Studies 1A and 1B) and heightened cholesterol (Study 2) compared with general information without reference to genetic risk factors as a between-subjects variable and risk perception and intention to engage in preventive behavior as dependent variables. RESULTS: All 3 studies revealed lower perceived susceptibility among participants who received information on genetic risk factors, which was associated with lowered intentions to engage in preventive behavior. In Studies 1A and 1B, these effects were observed only for previously unaware individuals, whereas in Study 2, they were observed for the entire sample. CONCLUSION: Alerting the public to the existence of genetic risk factors may not necessarily be beneficial to public health. Public health promoters should be aware of the possible adverse effects of alerting the general population to genetic risk factors, and should simultaneously educate the public about the meaning and consequences of such factors.