CO2 Treatments May Clear Alzheimer’s Proteins From The Brain

For a long time, the development of dementia has been associated with the buildup of proteins like amyloid plaques and tau.

Amyloid plaques are sticky bundles of abnormal protein fragments, while tau tangles are made up of stringy proteins. Combined, this pair has been compared to the “trigger and bullet” in dementia formation.

But scientists might have just made a step forward in dealing with them.

Neuropsychologist Dr Sephira Ryman, who led a team of researchers from The University of New Mexico School of Medicine and the Mind Research Network (MRN), reportedly presented her team’s findings at the Alzheimer’s Association International Conference in London last week. She explained that carbon dioxide can help to “pump” out tau before it can accumulate.

In 2025, Dr Ryman and her team published a paper which suggested that exposing the brain to low-level bursts of CO2 could help to “clear potentially toxic brain byproducts”.

It did this, they said, by activating our body’s glymphatic system. The glymphatic system removes waste from our brain (especially as we sleep) and seems to be impaired in people with conditions like Parkinson’s.

This initial paper found that three 10-minute sessions of inhaling higher-than-usual amounts of CO2 seemed to help Parkinson’s patients’ brains clear unwanted buildup – in this case, alpha-synuclein.

At the time, Dr Ryman said: “we realised that we could reproduce, in the awake state, the glymphatic clearing response usually linked to deep sleep using intermittent CO2”.

Dr Ryman has been involved in a study involving 12 people – eight of whom had normal tau levels, and four of whom had more tau buildup, New Scientist shared. Three of the four people had mild cognitive impairment, sometimes seen as a precursor to dementia.

The researchers scanned participants’ brains as they wore masks that released bursts of higher-CO2 air, switching from normal levels of the gas to much higher concentrations every 35 seconds for half an hour.

This seemed to activate their glymphatic system, and after the procedure was done, tau clearance appeared to be improved among those with high levels of it.

And all participants’ blood had higher levels of beta-amyloid (which can lead to the amyloid plaques we mentioned earlier) after the session too.

“This suggests this neurodegenerative marker was being cleared more out of the brain,” Dr Ryman said.

In a paper for the Journal of Cerebral Blood Flow and Metabolism, Dr Ryman and her colleagues said: “Breath-centered practices such as yoga, tai chi, and qigong have been utilised for centuries to manage stress and promote psychological well-being.

“Emerging research reveals an additional benefit: these practices also stimulate cerebrospinal fluid oscillations, potentially activating the glymphatic pathway during wakefulness.”

However, more research is needed to confirm their findings.

It’s also worth noting that the amyloid and tau-clearing power of the treatment seemed to stop an hour later (though the glymphatic system doesn’t work 24/7, either).

Additionally, some experts say we’re not yet sure whether clearing processes like these will definitely help to prevent or slow cognitive decline, even if they succeed.