The authors used NewsGuard’s Media Intelligence Dashboard to identify sites it had flagged for publishing health misinformation and MediaRadar to estimate advertising expenditures. NewsGuard had identified 1,229 such websites as of August 2025, but ad-spending data were available for only 11, an important limitation that narrows the paper’s scope.
Health misinformation funding was often indirect
Across those 11 sites, total estimated ad spending from all advertisers reached $336.4 million. Government and health-related organizations accounted for 10.6% of that total, while two sites — NewsMax and ZeroHedge — captured 67.3% of the spending from those categories. The study also found the annual total fell from $16.7 million in 2021 to $6.8 million in 2024, suggesting some improvement but not a clean break.
The mix of advertisers matters. Most of the $35.7 million did not come from federal agencies; the biggest slice came from nonprescription remedies and wellness products at $19.2 million, followed by medical service providers at $6.9 million and medical appliances, equipment, and devices at $4.2 million. Federal health agencies made up a much smaller share. The U.S. Department of Health and Human Services and its subsidiaries accounted for about $623,000, with the Centers for Medicare & Medicaid Services, the department itself, and the Centers for Disease Control and Prevention among the entities listed in the paper.
That distinction matters because the Office of the Surgeon General defines health misinformation as information that is false, inaccurate or misleading according to the best available evidence at the time. HHS says such claims contributed during the pandemic to vaccine refusal, rejection of public health measures and the use of unproven treatments.
Health misinformation concerns did not start with this paper
The new study adds a health-specific layer to a broader advertising problem that has been building for years. A 2024 Nature paper found that advertising on misinformation websites is widespread across industries and often amplified by automated ad-placement systems. Earlier, a 2022 ProPublica investigation documented how Google’s ad tools helped disinformation publishers in multiple countries keep earning money from false or misleading content.
The Yale authors said the practical risk goes beyond wasted marketing dollars. When public agencies and health brands appear beside dubious medical claims, the association can bolster reader trust in the surrounding content or erode trust in the advertiser itself. The paper’s conclusion was blunt: stronger restrictions may be needed to keep ads off websites that spread health misinformation.
The findings suggest the takeaway for public-sector communicators and health marketers is less about a single bad buy than a systemic blind spot. Programmatic advertising can place trusted brands in untrusted environments at scale, which means brand-safety controls, exclusion lists and regular audits are not just reputational safeguards — they are part of the fight against health misinformation.
