Exposure to low-credibility online health content is limited and is concentrated among older adults.

Older adults have been shown to engage more with untrustworthy online content, but most digital trace research has focused on political misinformation. In contrast, studies of health misinformation have largely relied on self-reported survey measures. Using linked survey and digital trace data from a national US sample (n = 1,059), we examine exposure to low-credibility health content across websites and YouTube. Here we show that the overall exposure to low-credibility health content is limited but increases with age and is not solely driven by the volume of health-related browsing. Importantly, those who believe inaccurate health claims are more likely to encounter low-credibility content, suggesting that exposure is not merely incidental. While older adults consume less content on YouTube overall, a higher proportion of what they view is from low-credibility sources. Additionally, individuals who consume low-credibility political news are significantly more likely to encounter low-credibility health content. This suggests a shared consumption profile that spans topics and platforms. These results raise new concerns about how online communication environments may potentially shape public health and well-being.