More than a third of social media posts about Alzheimer's blood tests suggested the tests could be used to screen healthy people with no signs of cognitive decline - something current clinical recommendations advise against. That finding comes from researchers at the University of Sydney, who published what they describe as the first study of its kind in the Journal of the American Geriatrics Society.
The team analysed 188 posts shared on Facebook, Instagram and TikTok between March 2014 and May 2025. The accounts behind those posts had a combined audience of more than 114 million followers, giving the claims considerable reach. Blood tests for Alzheimer's disease have been permitted in Australia only since July of this year, and lead author Dr Jenna Smith, of the University's School of Public Health and Sydney Health Literacy Lab, said the results arrive as public interest in these tests grows.
The gap matters because blood-based tests are a genuine advance for people who already have memory or thinking problems and need a clearer answer about the cause. Marketing them as a general check-up for anyone worried about their future is a different proposition entirely, and one that guidelines do not currently support. A positive result in someone without symptoms does not carry the same meaning, and can leave a person with anxiety and uncertainty rather than a diagnosis.
The study documents what is being said online rather than what people do in response, so it cannot tell us how many viewers went on to seek or buy a test. Still, it puts a number on a problem clinicians have been describing anecdotally as these tests move from research settings into commercial availability.