(I wrote this for a college class in 2023)
Meditation is growing in popularity as a practice. More and more people are choosing to implement the habit into their lives in hopes of improving mental well-being. Many studies demonstrate that meditation reduces stress and anxiety and can help with depression.
One area of research that has not been discussed enough is the physiological effects associated with the practice. Data shows that meditation has beneficial effects on brain function, genetic expression, and even gut microbiomes. The evidence is compelling enough to warrant implementing meditation into mainstream healthcare systems to support healing and prevent disease.
Effects on the Brain
One major area influenced by meditation is the brain. Spoon (2018) discovered that meditation is linked to functional changes in the amygdala and the ventromedial prefrontal cortex—circuits underlying emotional regulation and goal tracking.
Davidson et al. (2003) found that meditation was associated with significant increases in left-sided anterior activation, a pattern linked to positive affect and reduced negativity. The same study also found that meditation improved immune response to an influenza vaccine, with meditators producing more antibodies.
Numerous studies have found that meditation is associated with increases in brain volume and gray matter density (Hölzel et al., 2011). One area often enlarged in meditators is the right hippocampus, which plays a role in emotional regulation and response control (Luders et al., 2009).
Lazar et al. (2005) discovered that the thickness of the prefrontal cortex and right anterior insula correlated with meditation experience. Differences in cortical thickness were highest among older participants, leading researchers to suggest that meditation may help prevent age-related cognitive decline.
Pagnoni and Cekic (2007) compared elderly meditators with a control group and found significantly higher gray matter volume and attention performance among meditators.
Long-term meditation has also been shown to alter brain wave activity. Lutz et al. (2004) found increased gamma frequency activity in long-term meditators—patterns associated with heightened awareness and cognitive integration. Gamma frequencies are often linked to attention, learning, and emotional processing (Melinosky, 2023).
Effects on Gene Expression
Researchers have also examined how meditation alters gene function.
Kaliman et al. (2014) found that meditation caused rapid changes in gene expression and histone deacetylase activity, suggesting regulation of genes associated with stress and inflammation.
Other research found changes in genes associated with energy metabolism, insulin secretion, and inflammatory pathways. Bhasin et al. (2018) observed changes in 172 genes after just eight weeks of meditation practice, including genes regulating inflammation, circadian rhythms, and glucose metabolism.
Effects on the Gut Microbiome
Researchers from Shanghai studied Tibetan monks and their neighbors living in similar environments and consuming similar diets. They found that the meditators had a healthier and more diverse gut microbiome.
The bacteria enriched in meditators were associated with improved physical and mental health (Sun et al., 2023).
Conclusion
The evidence suggests that meditation has measurable physiological effects on the brain, immune system, gene expression, and gut microbiota.
Mainstream healthcare organizations should make greater efforts to encourage meditation as a preventative and supportive health practice. If people were more aware of how dramatically meditation can alter bodily functioning, they might be more inclined to prioritize it.
With chronic diseases on the rise (Ansah & Chiu, 2023), meditation may represent a valuable complementary strategy in addressing the current health crisis. Further research will help continue to substantiate and clarify these benefits.
References:
Ansah, J. P., & Chiu, C.-T. (2023). Projecting the chronic disease burden among the adult population in the United States using a multi-state population model. Frontiers in Public Health, 10.
Bhasin, M. K., et al. (2018). Specific transcriptome changes associated with blood pressure reduction in hypertensive patients after relaxation response training. The Journal of Alternative and Complementary Medicine, 24(5), 486–504.
Davidson, R. J., et al. (2003). Alterations in brain and immune function produced by mindfulness meditation. Psychosomatic Medicine, 65(4), 564–570.
Hölzel, B. K., et al. (2011). Mindfulness practice leads to increases in regional brain gray matter density. Psychiatry Research: Neuroimaging, 191(1), 36–43.
Kaliman, P., et al. (2014). Rapid changes in histone deacetylases and inflammatory gene expression in expert meditators. Psychoneuroendocrinology, 40, 96–107.
Lazar, S. W., et al. (2005). Meditation experience is associated with increased cortical thickness. NeuroReport, 16(17), 1893–1897.
Luders, E., et al. (2009). Larger hippocampal and frontal volumes in long-term meditators. NeuroImage, 45(3), 672–678.
Lutz, A., et al. (2004). Long-term meditators self-induce high-amplitude gamma synchrony. Proceedings of the National Academy of Sciences, 101(46), 16369–16373.
Melinosky, C. (2023). What to know about gamma brain waves. WebMD.
Pagnoni, G., & Cekic, M. (2007). Age effects on gray matter volume and attentional performance in Zen meditation. Neurobiology of Aging, 28(10), 1623–1627.
Spoon, M. (2018). Meditation affects brain networks differently in long-term meditators and novices. University of Wisconsin News.
Sun, Y., et al. (2023). Alteration of faecal microbiota balance related to long-term deep meditation. General Psychiatry, 36(1), e100893.*