Even as misleading and false claims continue to circulate widely across the internet, websites that host low-credibility health information remain relatively rare and attract limited attention overall. For most users, encounters with dubious medical content are infrequent and marginal compared with the vast amount of reliable information available online. This general pattern suggests that, despite frequent public concern about health misinformation, it does not dominate people’s everyday online experiences. However, this reassuring headline masks a more troubling underlying dynamic in how such content is actually consumed.
New research by communication scholars at the University of Utah sheds light on this imbalance by examining the real web-browsing behaviour of more than 1,000 adults in the United States over four weeks. Published in Nature Aging, the study combined survey responses with detailed tracking of participants’ online activity. While overall exposure to low-credibility health websites was low, the researchers found that traffic to these sites was highly uneven. Older adults, particularly those with right-leaning political orientations, accounted for a disproportionate share of visits.
This concentration raises particular concern because older adults are also the group most likely to seek out health information in general. As people age, they typically face more medical conditions and must make more frequent healthcare decisions, increasing their reliance on online sources. According to lead author Ben Lyons, this creates a troubling overlap between vulnerability and exposure. Although most older adults do not regularly engage with dubious medical content, those who do are clustered at the end of the distribution, meaning a small number of individuals bear most of the potential risk.
Lyons describes the findings as “good news with a catch”. On the positive side, only a small minority of participants visited even a single low-credibility health website during the study period, and such visits accounted for just a tiny fraction of all health-related browsing. This indicates that medical misinformation does not permeate the online environment as thoroughly as is sometimes assumed. At the same time, the heavy concentration of exposure among a narrow segment of users suggests that the problem, while limited in scale, may be intense in its effects for those affected.
The researchers also compared patterns of engagement with health misinformation to earlier findings on political misinformation. While older adults are significantly more likely to interact with and share misleading political content, the age effect for health information was noticeably smaller. Lyons suggests this difference reflects the social and emotional dynamics of online behaviour. Political content is often entertaining and tied to identity, making it more attractive to share, whereas health information lacks the same sense of group affiliation or competitive motivation.
To understand how users arrive at low-credibility health websites, the team examined referral data and browsing pathways. Surprisingly, they found little evidence that search engines, social media platforms, or partisan news outlets were driving this traffic. Instead, exposure appeared to be largely self-reinforcing. Users who visited one questionable site were likely to move on to others, often by navigating directly rather than being redirected. Combined with the finding that people holding conspiratorial or false health beliefs were more likely to encounter such content, the study suggests that health misinformation is embedded within broader patterns of online behaviour, making simple solutions difficult but targeted interventions increasingly important.
More information: Benjamin Lyons et al, Exposure to low-credibility online health content is limited and is concentrated among older adults, Nature Aging. DOI: 10.1038/s43587-025-01059-x
Journal information: Nature Aging Provided by University of Utah
