While decades of practice are linked to a younger-looking brain, a new 18-month trial suggests that turning back the clock isn’t quite so simple.
We all know our chronological age—the number of candles on our birthday cake. But in the world of neuroscience, another, more intriguing age is gaining attention: brain age. Using advanced imaging and machine learning, scientists can now look at the structure and activity of your brain and estimate its age, which may not perfectly match the number of years you’ve been alive. A “younger” brain age is a sign of health and resilience, while a “older” one can be a marker for increased risk of cognitive decline.
This raises a tantalizing question: can we do anything to slow down our brain’s aging process? For years, meditation has been touted as a powerful tool for mental well-being, stress reduction, and emotional balance. But could its benefits run deeper, right down to the physical integrity of our brains? A recent, comprehensive study set out to answer this very question, and its findings paint a fascinating and nuanced picture.
The Brains of the Experts
First, the researchers turned their attention to a unique group of individuals: older expert meditators. These weren’t casual practitioners; they were people who had dedicated a significant portion of their lives to the craft, accumulating an average of over 10,000 hours of practice—equivalent to working a full-time job for five years. The team compared their brains to those of cognitively healthy older adults of the same age who had no meditation experience.
To do this, they used a powerful machine-learning model fed with rich, multimodal neuroimaging data, including MRI scans to measure gray and white matter volume and PET scans to assess brain metabolism. From this data, the model predicted each person’s brain age. The difference between this predicted age and a person’s actual chronological age is called the Brain Predicted Age Difference, or BrainPAD. A negative BrainPAD suggests a brain that is aging more slowly than expected, while a positive one indicates accelerated aging.
The results were striking. The older expert meditators had significantly “younger” brains, with a more negative BrainPAD compared to their non-meditating peers. Even more compelling, there was a clear dose-response relationship: the more hours of meditation an expert had practiced over their lifetime, the younger their brain appeared. This suggests that the profound, long-term commitment to the practice was associated with preserved brain integrity. The effect wasn’t just abstract; this younger brain age in meditators was linked to tangible benefits, including better performance on mental imagery tasks and higher scores on measures of prosocial behavior, like empathy and compassion.
A Twist in the Tale: The 18-Month Trial
This first finding is exciting, but it raises a crucial follow-up question. Do you need to be a lifelong expert to see these benefits, or can beginners also turn back their brain’s clock? To find out, the researchers conducted the second part of their study: an 18-month randomized controlled trial called Age-Well.
They recruited over 130 older adults with no prior meditation experience and randomly assigned them to one of three groups:
- The Meditation Group: Participants engaged in a specially designed 18-month program involving weekly sessions and home practice focused on mindfulness and compassion.
- The Active Control Group: To control for the effects of learning a new skill and socializing, this group took a non-native language (English) class for the same duration.
- The Passive Control Group: This group had no intervention and simply continued with their normal lives.
Everyone underwent the same brain scans before and after the 18-month period. The hypothesis was that the meditation group would show a slowing of brain aging—a reduction in their BrainPAD—compared to the other two groups. But here’s where the story takes a turn. Contrary to expectations, the 18-month meditation training had no significant effect on brain age. The meditators’ brains didn’t appear to age any more slowly than the brains of those learning English or those in the no-intervention group.
Why the Difference? Unpacking the Puzzle
So, what gives? Why would long-term experts show such a profound effect while beginners showed none? The researchers offered several compelling explanations for this apparent contradiction.
First, and perhaps most obviously, is the matter of time. The expert meditators had been practicing for decades. An 18-month intervention, while substantial for a clinical trial, may simply not be long enough to induce the kind of large-scale structural and metabolic changes seen in the brains of lifelong practitioners. It could be that the brain-preserving effects of meditation are cumulative, requiring thousands of hours to become detectable on this scale.
Second, the participants in the trial were already exceptionally healthy. They were highly educated, active, and had high levels of cognitive and brain reserve to begin with. This creates a potential “ceiling effect,” where there is less room for improvement to be seen. It’s harder to measure the benefits of an intervention in a group that is already functioning at a very high level.
Finally, the tools used might not be capturing the whole story. While structural MRI and metabolic PET scans are powerful, they may not detect more subtle, functional changes. It’s possible the 18-month training improved brain function—like how different brain regions communicate with each other—in ways that aren’t reflected in brain volume or metabolism. Other techniques, like functional MRI (fMRI), might be needed to spot these earlier changes.
The Takeaway: A Marathon, Not a Sprint
This study provides a crucial piece of the puzzle in understanding meditation’s impact on the brain. It underscores that deep, lasting changes to the brain’s structure and health are likely the result of sustained, long-term practice. For those who have dedicated their lives to it, meditation appears to be associated with remarkable brain preservation.
However, the results from the 18-month trial are not a sign that meditation is useless for beginners. The practice has well-documented benefits for stress, attention, and emotional regulation that can improve quality of life, even if they don’t immediately shave years off your brain age. This study simply highlights that when it comes to physically altering the course of brain aging, the practice is likely a marathon, not a sprint. It reinforces the value of cultivating healthy habits not just for a few months, but as a lifelong commitment to well-being.
Reference
Arenaza-Urquijo, E. M., Gonneaud, J., Landeau, B., Houot, M., Mézenge, F., de La Sayette, V., … & Chételat, G. (2024). Impact of meditation on brain age derived from multimodal neuroimaging in experts and older adults from a randomized trial. Scientific Reports, 14(1), 12149. https://doi.org/10.1038/s41598-024-62649-9
