Slow breathing during meditation reduces levels of Alzheimer’s-related proteins in the blood

A new study published in the journal Psychophysiology provides evidence that the specific way a person breathes during meditation may determine its impact on biological markers related to Alzheimer’s disease. The research demonstrates that mindfulness meditation accompanied by deliberate slow breathing reduces levels of amyloid beta peptides in the blood. In contrast, mindfulness practice without this breathing component may actually increase levels of these same peptides.

Alzheimer’s disease is physically characterized by the accumulation of amyloid beta plaques in the brain. These plaques are formed from the aggregation of amyloid beta peptides, which are proteins produced as a normal byproduct of cellular activity.

When these peptides are produced at high rates or are not cleared effectively, they can clump together and disrupt brain function. Strategies to reduce the production or accumulation of these proteins are a major focus of preventative medicine.

Scientific literature has previously suggested that meditation might help slow brain aging and reduce the risk of dementia. However, it has been difficult to pinpoint which specific element of meditation drives these potential benefits.

Some practices emphasize mental training and focused attention, while others emphasize physical relaxation and breath control. The authors of the current study sought to disentangle these factors.

“When you are relaxed, whenever you breath in your heart rate increases and when you breath out it decreases. When you breathe slower, these oscillations in heart rate become larger,” said study author Mara Mather, a professor of gerontology, psychology and biomedical engineering at the University of Southern California.

“We found that daily sessions involving breathing slowly to increase oscillations in heart rate tends to decrease levels of amyloid-beta in the blood (see https://www.nature.com/articles/s41598-023-30167-0). Amyloid-beta is a peptide (a small protein) that is a normal byproduct of cellular activity that is, like other metabolic waste products, usually cleared out of the brain and body.

“However, if production levels are too high or clearance rates are not high enough, amyloid-beta levels increase and can start to aggregate (stick together) in the brain, forming amyloid-beta plaque, a signature feature of Alzheimer’s disease.”

“Slow breathing is an important feature of some types of meditative practices but not of other types,” Mather explained. “We were interested in whether slow breathing during meditation would decrease plasma amyloid-beta levels more than meditating without slow breathing.”

To investigate, the researchers recruited 108 participants. The final analysis included 89 healthy young adults between the ages of 18 and 35. The decision to use young adults allowed the researchers to observe physiological changes in a system that had not yet been altered by age-related disease pathology. The participants were screened to ensure they did not already have a regular meditation practice.

Before the main experiment, the team conducted pilot studies to refine their methods. They discovered that novice meditators do not naturally slow their breathing when asked to focus on their breath or body. Even when participants were instructed to focus on the sensations of the belly, their breathing rates remained similar to their resting rates. This finding necessitated explicit instructions for the slow-breathing condition in the main trial.

The participants were randomly assigned to one of three groups for a one-week intervention. The first group practiced mindfulness with slow breathing. They were instructed to inhale for a count of five and exhale for a count of five. This resulted in a pace of approximately six breaths per minute.

The second group practiced mindfulness with normal breathing. They were told to focus on the sensations of their belly but were not given a specific count or rhythm to follow. The third group served as a control and did not engage in any intervention.

“We did a lot of pilot testing and were surprised to find that, at least in novices, asking people to mindfully focus on their breath does not usually make them slow their breathing,” Mather noted. “Thus, we used mindful attention to breath as our active comparison condition.”

Participants in the two active groups practiced their assigned technique for 20 minutes twice a day. This totaled 40 minutes of daily practice for seven days. They used a laptop and a specialized heart rate sensor during their sessions. This equipment recorded their physiological data and ensured they were following the protocol. Blood samples were collected from all participants before the intervention began and again after the week concluded.

The analysis of the heart rate data confirmed that the groups performed as intended. The group assigned to slow breathing showed large oscillations in their heart rate during the practice sessions. This confirmed they were successfully engaging the parasympathetic nervous system. The group assigned to mindfulness with normal breathing did not show these oscillations. Their physiological state during the practice was similar to their resting state.

The blood analysis revealed distinct differences in amyloid beta levels between the groups. Participants who practiced mindfulness with slow breathing showed a decrease in plasma amyloid beta 40 and 42 levels. This reduction occurred after only one week of daily practice. The findings support the hypothesis that parasympathetic activation through breathing can alter how amyloid proteins are produced or cleared.

The results for the normal breathing group were different. Participants who practiced mindfulness without slowing their breath showed an increase in plasma amyloid beta levels. This increase aligns with the theory that the mental focus required for meditation can increase physiological arousal in novices. The effort to maintain attention may have stimulated the release of noradrenaline, driving the production of amyloid beta.

“Despite hearing all the same mindfulness instructions, the two conditions showed opposite effects after one week of daily practice,” Mather told PsyPost. “The mindfulness alone condition showed increases in plasma amyloid-beta while the mindfulness plus slow breathing condition showed decreases.”

“This raises the question of why mindfulness alone would increase amyloid-beta levels. Mindfulness requires focused attention. Noradrenaline is a neuromodulator that supports focused attention. Previous studies (see https://www.nature.com/articles/s41583-025-00911-8.epdf p. 287 for review) suggest that noradrenergic activity can increase amyloid-beta production, while muscarinic receptors that can sense vagus nerve activity tend to decrease amyloid-beta production.”

The control group showed no significant changes in amyloid beta levels over the one-week period. This stability in the control group strengthens the conclusion that the changes observed in the other groups were due to the specific interventions.

“Different types of meditative practices can have quite different effects on your physiology and attention,” Mather siad. “Each type of practice may have different benefits. Our findings suggest that practices that include slow breathing are more likely to decrease plasma amyloid-beta than those that do not.”

The researchers also measured tau proteins, another biomarker for Alzheimer’s disease. No significant changes were found in tau levels or in the ratio of amyloid types. The researchers noted that this was expected, as these markers typically take much longer to change or are more relevant in older populations with existing pathology.

In addition, the researchers assessed psychological outcomes. Participants completed questionnaires regarding their mood, stress, anxiety, and depression levels. Despite the clear physiological differences, there were no significant differences in emotional well-being between the groups at the end of the week. The researchers suggest that one week may be too short a duration to induce noticeable psychological improvements.

There are several potential misinterpretations to avoid when considering these results. A reduction in plasma amyloid beta does not guarantee a reduction in Alzheimer’s risk. While plasma levels are correlated with brain levels, they are not identical. It is also important to consider that the participants were young and healthy. It is not yet known if these effects would be identical in older adults or those with cognitive impairment.

Future research is needed to confirm if these changes in the blood reflect changes in the brain. The researchers are planning studies to measure amyloid beta in cerebrospinal fluid. This would provide a more direct assessment of brain health.

“We currently are working on getting funding to do a clinical trial in which we measure cerebrospinal fluid levels of amyloid-beta before and after a few weeks of slow breathing,” Mather told PsyPost. “Cerebrospinal fluid levels of amyloid-beta are low in healthy 20-year-olds and increase markedly until they get high enough that they start aggregating in brain tissue (usually around age 60 or 70).”

“If we see similar percent decreases in amyloid-beta levels in cerebrospinal fluid as we did in blood plasma, this would mean that people could dial back their amyloid-beta levels to about the levels of someone 5-10 years younger. This could potentially delay or prevent the amyloid-beta aggregation processes that seem to be such a critical trigger for Alzheimer’s disease.”

The researchers also aim to determine if these reductions in amyloid beta can be sustained over longer periods. If the effects are cumulative, daily slow breathing could potentially serve as a low-cost intervention to delay the onset of Alzheimer’s disease.

“No other behavioral intervention has been demonstrated to decrease amyloid-beta levels relative to a randomized control,” Mather said. “For instance, while sleep has been shown to reduce amyloid-beta levels every night, no one has designed a sleep intervention that reduces amyloid-beta better than our normal sleep. A critical next step for us to is to test what daily slow breathing does to amyloid-beta levels in the brain.”

The study, “A Randomized Clinical Trial Reveals Effects of Mindfulness and Slow Breathing on Plasma Amyloid Beta Levels,” was authored by Kaoru Nashiro, B Rael Cahn, Paul Choi, Hye Rynn J Lee, Shaakhini Satchi, Jungwon Min, Hyun Joo Yoo, Christine Cho, Noah Mercer, Lorena Sordo, Elizabeth Head, Jeiran Choupan, and Mara Mather.