Google’s search function AI Overviews cites YouTube greater than any medical web site when answering queries about well being situations, in keeping with analysis that raises recent questions on a device seen by 2 billion individuals every month.
The corporate has stated its AI summaries, which seem on the high of search outcomes and use generative AI to reply questions from customers, are “dependable” and cite respected medical sources such because the Facilities for Illness Management and Prevention and the Mayo Clinic.
Nonetheless, a examine that analysed responses to greater than 50,000 well being queries, captured utilizing Google searches from Berlin, discovered the highest cited supply was YouTube. The video-sharing platform is the world’s second most visited web site, after Google itself, and is owned by Google.
Researchers at SE Rating, a search engine optimisation platform, discovered YouTube made up 4.43% of all AI Overview citations. No hospital community, authorities well being portal, medical affiliation or educational establishment got here near that quantity, they stated.
“This issues as a result of YouTube will not be a medical writer,” the researchers wrote. “It’s a general-purpose video platform. Anybody can add content material there (eg board-certified physicians, hospital channels, but additionally wellness influencers, life coaches, and creators with no medical coaching in any respect).”
Google instructed the Guardian that AI Overviews was designed to floor high-quality content material from respected sources, no matter format, and quite a lot of credible well being authorities and licensed medical professionals created content material on YouTube. The examine’s findings couldn’t be extrapolated to different areas because it was performed utilizing German-language queries in Germany, it stated.
The analysis comes after a Guardian investigation discovered individuals have been being put susceptible to hurt by false and deceptive well being info in Google AI Overviews responses.
In a single case that specialists stated was “harmful” and “alarming”, Google offered bogus details about essential liver operate exams that might have left individuals with critical liver illness wrongly pondering they have been wholesome. The corporate later eliminated AI Overviews for some however not all medical searches.
The SE Rating examine analysed 50,807 healthcare-related prompts and key phrases to see which sources AI Overviews relied on when producing solutions.
They selected Germany as a result of its healthcare system is strictly regulated by a mixture of German and EU directives, requirements and security rules. “If AI techniques rely closely on non-medical or non-authoritative sources even in such an atmosphere, it suggests the difficulty might prolong past any single nation,” they wrote.
AI Overviews surfaced on greater than 82% of well being searches, the researchers stated. Once they checked out which sources AI Overviews relied on most frequently for health-related solutions, one outcome stood out instantly, they stated. The only most cited area was YouTube with 20,621 citations out of a complete of 465,823.
The subsequent most cited supply was NDR.de, with 14,158 citations (3.04%). The German public broadcaster produces health-related content material alongside information, documentaries and leisure. In third place was a medical reference website, Msdmanuals.com with 9,711 citations (2.08%).
The fourth most cited supply was Germany’s largest shopper well being portal, Netdoktor.de, with 7,519 citations (1.61%). The fifth most cited supply was a profession platform for medical doctors, Praktischarzt.de, with 7,145 citations (1.53%).
The researchers acknowledged limitations to their examine. It was performed as a one-time snapshot in December 2025, utilizing German-language queries that mirrored how customers in Germany usually seek for well being info.
Outcomes may differ over time, by area, and by the phrasing of questions. Nonetheless, even with these caveats, the findings nonetheless prompted alarm.
Hannah van Kolfschooten, a researcher specialising in AI, well being and regulation on the College of Basel who was not concerned with the analysis, stated: “This examine offers empirical proof that the dangers posed by AI Overviews for well being are structural, not anecdotal. It turns into troublesome for Google to argue that deceptive or dangerous well being outputs are uncommon circumstances.
“As a substitute, the findings present that these dangers are embedded in the best way AI Overviews are designed. Particularly, the heavy reliance on YouTube moderately than on public well being authorities or medical establishments means that visibility and recognition, moderately than medical reliability, is the central driver for well being data.”
A Google spokesperson stated: “The implication that AI Overviews present unreliable info is refuted by the report’s personal information, which reveals that probably the most cited domains in AI Overviews are respected web sites. And from what we’ve seen within the revealed findings, AI Overviews cite knowledgeable YouTube content material from hospitals and clinics.”
Google stated the examine confirmed that of the 25 most cited YouTube movies, 96% have been from medical channels. Nonetheless, the researchers cautioned that these movies represented fewer than 1% of all of the YouTube hyperlinks cited by AI Overviews on well being.
“Most of them (24 out of 25) come from medical-related channels like hospitals, clinics and well being organisations,” the researchers wrote. “On high of that, 21 of the 25 movies clearly be aware that the content material was created by a licensed or trusted supply.
“So at first look it appears to be like fairly reassuring. Nevertheless it’s essential to keep in mind that these 25 movies are only a tiny slice (lower than 1% of all YouTube hyperlinks AI Overviews truly cite). With the remainder of the movies, the state of affairs might be very totally different.”
