Objective: To determine how often press releases and news articles contain exaggeration and to locate its origin in the trajectory from research paper to news article., Design: Retrospective quantitative content analysis., Method: We analysed press releases on health-related research published by Dutch universities and university medical centres in 2015 (n = 129) as well as news media articles related to those press releases (n = 185)., Results: 20% of press releases and 29% of news articles exaggerated the conclusion or causal claim. Explicit health advice was, when present, exaggerated in 7% of press releases and 10% of news articles. When press releases exaggerated the conclusion or causal claim, 92% of associated news articles contained the same exaggeration. When the conclusion was not exaggerated in the press release, 6% of the news articles was exaggerated. The relative chance for exaggerated news associated with exaggerated press releases was 16.08 (95% CI: 7.35-35.18). Exaggerated press releases were associated with news articles more frequently. The relative chance for news articles to be associated with exaggerated press releases vs. a non-exaggerated press release was 1.45 (95% CI: 1.02-2.04)., Conclusion: Exaggeration in health-related news is strongly correlated with exaggeration in the original press release and occurs in more than 1 in 5 articles. Monitoring and, if necessary, improving the accuracy and correctness of academic press releases seem to be important measures to improve the quality of health related news., Conflict of interest and financial support: I. Smeets is a columnist with one of the newspapers investigated. She was not involved in collecting, coding and analysing the relevant data. Additional potential conflicts of interest have been reported for this article. ICMJE forms provided by the authors are available online along with the full text of this article.