<p>   </p> <p>Health-related misinformation presents a significant threat to public health and wellbeing. Misinformation exposure is associated with decreased compliance with public health initiatives, decreased trust in science, and greater levels of disease transmission. Unfortunately, fact-checking is not a panacea for mitigating the negative effects associated with misinformation exposure. The present dissertation, guided by the Theory of Planned Behavior, investigated across two studies whether providing participants with different levels of media literacy education could enable them to successfully determine news articles, on a variety of different health topics, contained either legitimate or illegitimate information. Both studies utilized a three-group, pretest-posttest, between-subjects experimental design in which participants were randomly assigned to either a brief or detailed media literacy skill promotion message, or a no-message control. The messages took the form of Facebook posts from a fictitious organization dedicated to promoting media literacy. The first study recruited 305 undergraduate students. Results from the first study indicated that participants assigned to the detailed message condition were more successful compared to the other conditions in identifying health-related misinformation. A content analysis of participants’ open-ended responses revealed that participants in the detailed message group were the most likely to utilize skills related to media literacy and were the least likely to utilize heuristics or to guess when determining whether news articles contained legitimate or illegitimate information. The second study sought to replicate and extend the results of the first study in a sample of adults recruited through Amazon’s Mechanical Turk. The results of the second study found that the detailed message condition promoted a greater ability to identify misinformation compared to either the brief message or control condition. Similarly, participants in the second study were most likely to use skills related to media literacy when completing the misinformation identification task. The results suggest that brief media literacy messages may be insufficient in enabling participants to successfully identify health-related misinformation online. However, more detailed media literacy education messages show promise for potentially limiting the spread of misinformation online. Theoretical and practical implications are discussed. </p> <p>  </p>