MONDAY, Sept. 21, 2026 (HealthDay News) — Social media posts are making too many false promises about the newly available blood tests for Alzheimer’s disease, a new study warns.

More than a third of posts on Facebook, Instagram and TikTok that focused on the blood tests say they can be used to screen healthy people without signs of brain decline, researchers report in the Journal of the American Geriatrics Society.

That simply isn’t so. Guidelines specifically rule out using the blood tests on people with healthy cognitive function, researchers said.

Further, accounts with explicit financial interests — such as companies offering direct-to-consumer blood testing — were more than three times as likely to promote the tests for people who don’t have any symptoms of Alzheimer’s or dementia, researchers said

“Social media is presenting exciting claims about what these new blood tests might be able to do, but that excitement can outpace the evidence,” lead researcher Jenna Smith, a postdoctoral research fellow at the University of Sydney in Australia, said in a news release.

In May 2025, the U.S. Food and Drug Administration (FDA) approved the first blood test developed as a tool to help diagnose Alzheimer’s, according to Harvard Medical School. The test, Lumipulse, looks for proteins in the bloodstream that have been linked to toxic plaques and tangles in the brains of Alzheimer’s patients.

These blood tests are intended to support diagnosis of Alzheimer’s in people already experiencing cognitive decline, researchers said.

But a review of 188 posts shared between March 2014 and May 2025, on accounts with a combined audience of more than 114 million, found that:

• 36% of posts said the blood tests could be used to diagnose seniors with no signs of brain impairment.

• 59% of posts promoted the tests as useful for earlier or improved diagnosis, but many failed to mention that the tests by themselves cannot form the basis of a diagnosis.

• Only 36% of posts included evidence supporting their claims.

• Fewer than one-quarter cited any specific study.

“We know people turn to social media for health information,” Smith said. “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.”

The posts often omit important information as well, researchers said. For example, posts discussing testing rarely mentioned potential harms like overdiagnosis or false positives.

“Dementia is one of the most feared health conditions among adults,” Smith said. “Understandably, people want answers and may be drawn to new tests that appear to offer certainty or early detection. But for people without symptoms, there’s currently no evidence that screening provides a benefit.

“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,” Smith continued. “People with no symptoms could be diagnosed with Alzheimer’s disease but not go on to develop dementia that impacts their life.”

The results point to a need for clear, evidence-based information to help people understand who may benefit from testing and what the results can and cannot tell them, Smith 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,” she said.

“It’s important that consumers are getting balanced information rather than relying on social media alone,” Smith said. “Posts should always include advice to speak with a health professional before undertaking any Alzheimer’s blood testing.”

More information

The Mayo Clinic has more on FDA-approved blood tests for diagnosing Alzheimer’s disease. 

SOURCES: University of Sydney, news release, Sept. 16, 2026; Journal of the American Geriatrics Society, Sept. 15, 2026