In my last Yoga Digest article, we explored the concept of neuroplasticity as it relates to yoga and mindfulness. In this article, we dive a little deeper and investigate epigenetics. If you haven’t already heard this buzz word, now is your time. The term epigenetics itself is very often misunderstood and misinterpreted, so even if you have heard it, we’ll spend a bit of time unpacking what it actually means but keep in mind, this is the speed-dating version. Careers are spent on this stuff!
Essentially, the epigenome can be thought of as sitting on top of the genome (or DNA). To get a visual, think of a textbook where the printed words represent your DNA. Let’s say you go in and highlight a few sentences with a yellow highlighter. That yellow highlight can be thought of as the epigenome. It sits on top of the words but doesn’t change the words. What it changes is the emphasis; i.e., when you go back to review that section, those highlighted sentences will be emphasized (or increased gene expression). Alternatively, you could use a black marker to cross out sentences and, in that case, it would be really challenging to read those sentences again (this would decrease gene expression). Again, the words didn’t change, but your ability to read them did. Theoretically, epigenetic changes are one mechanism by which environmental exposures can ‘get under the skin’ to affect the underlying biology of a system. While there are multiple epigenetic ‘marks,’ this article will only discuss two of them: DNA methylation and telomere length. DNA methylation happens when a chemical group (called a methyl group) acts like a little sticker that adheres to specific segments of the genome. Telomeres are the end of our chromosomes and they are known to shorten as we age.
There is a small, but growing, body of research suggesting that mindfulness-based techniques, such as yoga and meditation, induce changes to our biology, particularly our biology related to stress. Luders and Kurth (2019) describe meditation as an active mental process that, when done repeatedly, regularly, and over longer periods of time, can change our biology. This is due, in part, to the fact that meditation incorporates efforts in multiple domains: awareness, attention, concentration, and focus. Yoga is a mind-body practice incorporating many of these same qualities alongside movement. There is accumulating evidence of positive effects on yoga on mental health, physical health, and well-being (Tolahunase et al., 2018). This has led some researchers to suggest that mindful-based practices, such as yoga and meditation, hold promise as evidence-based treatment for mental health disorders, such as depression (Goldberg et al., 2018).
How does this happen? Most of us that practice yoga and mindfulness techniques likely feel a shift in mood after practicing, but I suspect most of us, don’t sit back and think deeply about what is happening biologically to create this shift. One possible path is through neuroplasticity, which was the focus in my last Yoga Digest article. But we can zoom the microscope in even deeper to look at cellular changes! There are currently a handful of studies examining epigenetic mechanisms as one other possible avenue by which yoga and mindfulness can affect our biology. As one example, Garcia-Campayo et al. (2018) compared the methylome (i.e., 450,000 epigenetic methylation markers across the entire genome) of experienced meditators (10+ years) to non-meditators and found differential methylation at 43 genes. What is differential methylation? It’s when there is more (or less) methyl groups attaching themselves to the DNA in meditators vs non-meditators. The majority of these 43 genes that showed different levels of methylation between the two groups have been suggested to be involved in neurological and psychiatric disorders, cardiovascular disease and cancer. These researchers went on to perform experiments to show that the epigenetic response to mindfulness may modulate (or change) inflammatory pathways supporting the potential of meditation-based-interventions in the treatment of chronic inflammatory conditions. This work was supported by very recent work by Chaix et al. (2020), also comparing meditators to non-meditators, who found differential methylation in 61 genes involved in immune-related (and thus likely stress- related) pathways.
An additional study by Chaix et al. (2017) focused on the epigenetic aging rate. Did you know that there are specific patterns in the genome that can predict the rate of aging? These show up in DNA methylation patterns and also in telomere length, both of which are considered epigenetic markers. Further, cumulative life stress and trauma can accelerate our epigenetic clock and these faster clocks are associated with age-related chronic diseases. Slower clocks, however, predict longevity as well as better cognitive and physical fitness. And, guess what? Meditation and yoga decreased the epigenetic aging rate, with the more years of formal practice predicting increased protective effects on epigenetic aging markers. I don’t know about you, but I want a slower epigenetic clock.
Kaliman (2019) cautions us, however, that this area of research is in its infancy. As a mental health researcher who studies epigenetics as it relates to ADHD-like behaviors, I couldn’t agree more. We need other research groups to replicate (or find similar results) what has been done, ideally in larger and more controlled studies. We also need to be able to speak to the long- terms effects of epigenetic changes. There might also be sensitive developmental periods more conducive to epigenetic changes. And so many more questions beyond the scope of this article. Despite this, however, I feel encouraged. We know, experientially, that mindfulness-based techniques are highly effective in stress reduction, and it now appears possible that such stress reduction may also mediate changes deep in our cells (Kaliman, 2019).
If you don’t already have a yoga or mindfulness practice, here are simple tips to get you started:
1. Bring meditation into your daily practice. Starting with just 3 minutes a day and building to 10 minutes over time. If sitting down to meditate feels too daunting, try a walking meditation. This isn’t just going on a walk. Being barefoot is really helpful for this approach as it will help you stay very aware of each blade or grass or grain of sand or plank of wood floor. You could literally walk back and forth over the same area trying tostay very focused on the feeling of each movement of your feet, noticing your mind wandering, and staying super present in your experience.
2. If meditating just feels like it’s too inaccessible, try practicing mindfulness as you practice yoga or exercise. When you find your mind wandering or creating your grocery list, bring it back to what you are doing. What muscles are engaging in the pose you are in? What muscles are lengthening? Mentally watch your breath coming in and exhaling out. What is the temperature of the air as you breathe in? As you breathe out? There are countless ways to keep your mind present while you practice and move.
If you couldn’t already tell, I have a tendency to completely nerd out about this type of thing. Our bodies are built to be resilient and to change. And, that change doesn’t have to be negative. In fact, changes can be positive. We have the capacity to change our habitual patterns, which could, in turn, create positive changes in our internal landscape—even at the deep layers of our cells and the ways our genes are expressed.
Change our immune response? Change our inflammatory response? Slow down our epigenetic aging clock? Ummm….yes, please!