Objective: Health misinformation on social media threatens public health. One question that could lend insight into how and through whom misinformation spreads is whether certain people are susceptible to many types of health misinformation, regardless of the health topic at hand. This study provided an initial answer to this question and also tested four hypotheses concerning the psychosocial attributes of people who are susceptible to health misinformation: (1) deficits in knowledge or skill, (2) preexisting attitudes, (3) trust in health care and/or science, and (4) cognitive miserliness. Method: Participants in a national U.S. survey (N = 923) rated the perceived accuracy and influence of true and false social media posts about statin medications, cancer treatment, and the Human Papilloma Virus (HPV) vaccine and then responded to individual difference and demographic questions. Results: Perceived accuracy of health misinformation was strongly correlated across statins, cancer, and the HPV vaccine (rs ≥ .70), indicating that individuals who are susceptible to misinformation about one of these topics are very likely to believe misinformation about the other topics as well. Misinformation susceptibility across all three topics was most strongly predicted by lower educational attainment and health literacy, distrust in the health care system, and positive attitudes toward alternative medicine. Conclusions: A person who is susceptible to online misinformation about one health topic may be susceptible to many types of health misinformation. Individuals who were more susceptible to health misinformation had less education and health literacy, less health care trust, and more positive attitudes toward alternative medicine. (PsycInfo Database Record (c) 2021 APA, all rights reserved).