A small study has found that inhaling high levels of carbon dioxide intermittently for half an hour can flush proteins linked to Alzheimer’s disease from the brain. The approach mimics the brain’s natural waste-clearing activity during deep sleep. Researchers presented the findings last week at the Alzheimer’s Association International Conference in London.
Sephira Ryman at the University of Texas at Austin led the research, which involved 12 participants. Eight had no cognitive impairment, while four showed elevated tau levels and three had mild cognitive impairment. Participants wore a mask that alternated between normal air and air with 5 percent carbon dioxide every 35 seconds for 30 minutes.
The intervention caused blood vessels in the brain to dilate and constrict in a pattern similar to deep sleep, activating the glymphatic system. Blood samples taken 15 minutes after the session showed increased levels of beta-amyloid in all participants, indicating clearance from the brain. Tau clearance improved only in those with signs of cognitive decline.
The effects returned to baseline within an hour. No side effects occurred during the study. Further research is needed to determine long-term impacts on Alzheimer’s risk and progression, according to experts including Vincent Tay and Jeff Iliff.
