Google’s AI Overviews feature cites YouTube more often than any medical website when answering health-related searches, according to a new German study that raises concerns about how health information is surfaced to users.
Researchers analysed more than 50,000 health queries in Germany and found that AI Overviews, which appear at the top of search results, cited YouTube in 4.43% of all references – more than hospitals, government health portals or medical associations. YouTube was the single most cited domain overall, despite not being a medical publisher.
The study, conducted by SE Ranking, found AI Overviews appeared in over 82% of health searches. While some YouTube videos cited came from hospitals or licensed professionals, researchers warned these represented less than 1% of all YouTube links used, meaning much of the cited content could come from creators without medical training.
Google said its system is designed to surface high-quality information across formats and that many credible health authorities publish content on YouTube. However, experts said the findings suggest the risks of misleading health information are structural, not isolated, and that popularity may be outweighing medical authority in how AI Overviews select sources.
The research adds to growing scrutiny of Google’s AI-generated health summaries, which are seen by billions of users each month.
