A simple breathing technique practised for 20 minutes twice daily could lower the risk of developing Alzheimer's disease, according to researchers at the University of Southern California (USC). The study, published by the USC Leonard Davis School of Gerontology, involved 108 participants aged 18 to 80 who performed the exercise over four weeks.
The technique involves inhaling for five seconds and exhaling for five seconds. Half the group followed this paced breathing guided by a laptop screen, while the other half focused on calming thoughts and keeping their heart rate steady. Blood samples taken before and after the four-week period showed that levels of amyloid beta proteins—linked to Alzheimer's—decreased significantly in the paced-breathing group.
Amyloid beta peptides, particularly types 40 and 42, are toxic proteins that neurologists believe may directly cause Alzheimer's disease. The researchers suggest that the breathing exercise influences heart rate variability, which in turn affects the nervous system and the brain's ability to produce and clear these proteins.
As we age, our ability to activate the parasympathetic nervous system—responsible for rest and digestion—declines, leading to reduced heart rate variation. The breathing exercise appears to restore this function, potentially lowering Alzheimer's risk. Study author Professor Mara Mather noted that while the sympathetic and parasympathetic systems are known to influence Alzheimer's-related peptides, little research has explored how age-related physiological changes contribute to the disease.
