New Australian research has highlighted how certain social media posts are spreading misinformation about blood tests.
“You really think someone would do that? Just go on the internet and tell lies?” – Buster Baxter
The promotion of blood tests for Alzheimer’s disease – which test for levels of phosphorylated tau 217 in the plasma – or genetic tests for the apolipoprotein E ε4 allele have been allowed in Australia since July this year. While it is believed that blood-based biomarkers and genetic tests could help diagnose AD earlier, there are concerns around how these tests are being represented on social media.
Dr Jenna Smith (PhD), a postdoctoral research fellow in the School of Public Health at the University of Sydney, has spearheaded a study exploring how social media content discusses these blood tests. Her findings have been published in the Journal of the American Geriatrics Society.
“Social media is presenting exciting claims about what these new blood tests might be able to do, but that excitement can outpace the evidence,” Dr Smith told media.
“We know people turn to social media for health information. When content leaves out important context about who these tests are for, their limitations and potential downsides, there’s a risk people may develop unrealistic expectations or seek testing that isn’t recommended for them.”
Dr Smith and her collaborators undertook a cross-sectional content analysis of 188 posts found by searching three social media platforms for “dementia blood test” or “Alzheimer’s blood test”. They identified 64 posts from Facebook, 85 from Instagram, and 39 from TikTok that were posted to more than 114 million followers between March 2014 and May 2025. Content published in a language other than English was excluded.
Roughly one third of posts (67, 36%) were made by an individual as opposed to an organisation, with around half of these individuals (31, 46%) able to be identified as a physician.
One in three posts described the utility of asymptomatic screening for AD and other forms of dementia, but only 12% of posts included information about the potential harms of screening (e.g., false positives, overdiagnosis, etc.). Similarly, more than half of the observed posts (59%) claimed the test could result in an earlier or improved diagnosis, but fewer than one fifth of posts described the role of a clinician or healthcare professional in the test.
Less than half of the posts (36%) mentioned there was evidence associated with the test it promoted, and only a quarter of those cited a specific study that could be identified by the researchers. Although most posts were deemed to be of an educational or informative nature (81%), a similar proportion conveyed a promotional tone (75%). Around one in five posts highlighted the need for future research into blood tests for dementia (22%).
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Dr Smith felt that tests that claim to offer certainty or early detection may be appealing to consumers but stressed that there is no evidence that screening offers any benefit for people who are not experiencing any symptoms of dementia.
“A positive result may create anxiety and uncertainty, particularly when there is no cure for Alzheimer’s disease and guidance on how these new tests should be used is still evolving,” she said.
“These tests may play an important role in supporting diagnosis for some people experiencing cognitive symptoms, but they should be interpreted with appropriate clinical oversight.”
The researchers concluded that clinicians needed to be aware of the extent to which social media posts could be influencing how consumers viewed blood tests for AD and other forms of dementia, noting that the individuals and organisations posting the content could be taking advantage of people’s fear of developing dementia.
“Whilst structural regulation on social media is inadequate, resources to support clinicians navigating discussions about AD blood tests should be developed and disseminated, including information that distinguishes between clinical utility in symptomatic individuals as opposed to asymptomatic individuals,” the researchers concluded.
“Resources should detail the limitations of blood-based biomarkers, advice on what to do next in someone with a positive test, and the potential harms of early diagnosis when there is currently no curative treatment for AD.”
Journal of the American Geriatrics Society, 15 September 2026
