Yoga and meditation have been practiced for thousands of years, but only in the last two decades have scientists begun to understand how these techniques influence human physiology. Advances in brain imaging, hormone analysis, immune profiling, and molecular biology now allow researchers to measure what happens inside the body when people engage in mind–body practices. This article summarizes current findings in simple language based on peer-reviewed research.
Yoga involves physical postures, controlled breathing, and intentional attention. Meditation focuses on training the mind to remain aware, observe thoughts, or maintain a calm state. Although the practices differ, research consistently shows that both influence the autonomic nervous system. They enhance parasympathetic activity, which supports rest and recovery, and reduce excessive sympathetic activation, which is associated with stress. Cahn (2017) found that individuals who participated in a three-month yoga and meditation retreat had more stable daily levels of cortisol, which is the body’s primary stress hormone. A steady cortisol rhythm is a sign that the stress-response system is functioning more effectively.
Brain-imaging studies show that meditation can change how different brain networks communicate. Jinich-Diamant (2025) observed that a week-long meditation-based retreat reduced activity within the default mode network, which is the system involved in mind-wandering and internal chatter. After the retreat, participants’ brains showed less rigid connectivity patterns, indicating greater flexibility. The same study produced a notable laboratory finding. When researchers added blood samples from participants collected after the retreat to cultured neuronal cells, the neurons developed longer neurites. Neurite outgrowth is a biological indicator of neuroplasticity, meaning the brain’s ability to create and strengthen new neural connections.
Yoga and meditation also influence immune activity. Cahn (2017) reported shifts in inflammatory markers, including increases in anti-inflammatory cytokines and decreases in certain pro-inflammatory ones. Cytokines are signaling molecules used by the immune system, and changes in their levels indicate adjustments in immune regulation. Burić (2018) found that meditation can even reduce the activity of genes involved in chronic inflammation, particularly those associated with the NF-κB pathway, which plays an important role in regulating inflammatory responses.
Recent studies have expanded this research into molecular and metabolic pathways. Jinich-Diamant (2025) analyzed blood samples before and after a meditation retreat and identified measurable changes in metabolites involved in energy production, such as glycolysis, and in pathways related to amino-acid metabolism. The same study found alterations in microRNAs carried in exosomes, which are tiny vesicles that allow cells to send regulatory messages to one another. These findings suggest that meditation may influence not only organs and systems but also the molecular communication occurring between cells.
Taken together, current research shows that yoga and meditation can influence multiple biological systems at once. They affect brain networks, stress hormones, immune signaling, gene expression, and metabolic processes. These findings are helping modern biomedical science understand practices that have existed for thousands of years, creating a bridge between ancient traditions and contemporary biological research.
References
Jinich-Diamant, A., Patel, H. H., Le Nguyen, K. D., Hong, E. S., Eshraghi, L., Marquina, S., Anbaran, D., Jinich, S., Dobkins, K. R., & Mills, P. J. (2025).
Neural and molecular changes during a mind–body reconceptualization, meditation, and open-label placebo healing intervention. Communications Biology, 8, Article 90.
https://doi.org/10.1038/s42003-025-09088-3Cahn, B. R., Goodman, M. S., Peterson, C. T., Maturi, R., & Mills, P. J. (2017).
Yoga, meditation and mind–body health: Increased BDNF, cortisol awakening response, and altered inflammatory marker expression after a 3-month yoga and meditation retreat. Frontiers in Human Neuroscience, 11, 315.
https://doi.org/10.3389/fnhum.2017.00315Burić, I., Farias, M., Jong, J., Mee, C., & Brazil, I. A. (2018).
What is the molecular signature of mind–body interventions? A systematic review of gene expression changes induced by meditation and related practices. Frontiers in Immunology, 9, 671.
https://doi.org/10.3389/fimmu.2018.00671