Your genome is contained in two strands of DNA woven together into a double helix and separated into 23 pairs of chromosomes. You got half of your genes from your mother and half from your father, recombined in a way to make a completely unique human. Rosalind Franklin gave us the first insight into the double helix structure of DNA from her work in X-ray crystallography, then had her notes stolen by the boy’s club while she got cancer and died as a byproduct of her work around radiation. But I digress.
Genomic structure and function has been studied with great curiosity since the middle of the 20th century, and many of the secrets of DNA have been decoded. DNA encodes for all of the proteins that make up your body, and that includes both your physical structures like muscles and bones as well as enzymes, hormonal signaling molecules, and the repair machinery that maintain the integrity of the DNA itself.
The core structure of your genome will never change, but the way they are expressed can. How and what you can do to unlock this potential is what you’ll be learning in a few minutes. Imagine living through an entire cycle of evolution in the span of a single lifetime! There are many mysteries yet to unravel, and this is one that I’m personally fascinated with: the epigenome.
What is epigenetics?
Epigenetics is the study of how gene expression can be altered. Epi- means “above,” and in this case we’re talking about methyl tags that are attached to the outside of DNA strands. A methyl tag consists of one carbon atom with three hydrogens bound to it. (If you’re having flashbacks of ochem, don’t worry, there won’t be a test at the end.) If a section of DNA has a lot of methyl tags on it, it’s said to be “highly methylated.” Highly methylated regions of DNA are wound tightly and are difficult, if not impossible, to be translated into proteins that cells can use. Less methylated sections are looser and are more easily translated.
And you can change what gets methylated.
Methylation patterns change in response to the inputs you give your body, and these patterns change constantly. Methyl tags are added and deleted based on the inputs you give your genes. These inputs include activity level, nutrient availability, mood and stress level, air quality, and literally everything you come in contact with. Anything that affects your body serves as an input to your epigenome, which then responds accordingly, and quickly.
If you need a kick in the pants to lose weight or quit smoking, here it is: methyl tags get added to regions linked to repair and regeneration when we have unhealthy lifestyles. This means that not only do poor choices directly impact your health, but they persist and amplify through epigenetic shifts that decrease your overall capacity for healing.
Inflammation is so pervasive a problem in terms of longevity that it’s being accurately called “inflammation” for how damaging it is to all your tissues. In individuals who habitually choose unhealthy lifestyles, regions of DNA linked to decreased inflammation are highly methylated, and the pathways that help mediate regeneration are impaired. Pain, tissue damage, immunological dysfunction, and accelerated aging can result from chronic inflammation that never gets resolved because the DNA that codes for repair mechanisms is too tightly wound to be used.
But poor choices aren’t the only way we can impact the epigenome.
Consumption of healthy foods rich in nutrients, regular physical activity, and regular restorative sleep all help to activate genes involved in the body’s repair mechanisms. Habitually making lifestyle choices that support health encourage methylation patterns that encourage regeneration and repair. Someone who has healthy habits and has an epigenome that supports regeneration will age more slowly and suffer fewer chronic and debilitating illnesses.
Let’s take a deeper look at one example of how the epigenome is shifted: obesity.
Weight isn’t just a study in the laws of thermodynamics. We all know someone who can inhale whole pizzas and not gain weight just as we know someone who can look at a cupcake and gain 5 pounds. (Lucky me, I’m the latter.) We all have some mix of the dozens of genes that promote both leanness and fat, which is one of the reasons we don’t all lose and gain weight in the same way. It’s also why some ways of eating help some people get to their ideal body composition while other people that follow the same plan will both feel worse and gain excess fat. Pigeyre et al. presented a 34-page report in 2016 in which they investigated a number of factors in an attempt to turn on the epigenetic switches for leanness genes while turning them off for obesity genes.
What the researchers on this paper found is that there are 52 obesity-related genes (that we know of, and that probably play a role in other bodily functions), and 107 areas in which changes in the methylation pattern may influence gene transcription. They found that adipose (fat) cells show the most prominent epigenetic alterations, where other cell types were less affected. This points to adipose tissue being metabolically active, which means it can be impacted by the decisions we make, down to an epigenetic level.
According to a 2014 article by Alfredo, et al., insulin-like growth factor 2 (IGF2) is a key gene that can contribute to obesity. Excessive calorie consumption can alter the expression of this growth factor, which is important for both age-dependent development and muscle-building throughout your life. Furthermore, in 2019, de Toro-Martin, et al. found that obesity-related epigenetic alterations accelerated aging in all organs, not just adipose tissue.
When it comes to epigenetics, things can get complicated quickly, and we still have a lot to learn. The take-home message is that we have the potential to modify our epigenome to favor health rather than disease by our own decisions…and the changes begin immediately. You can begin to heal even if you’ve had only unhealthy choices for your whole life, even in the womb.
You can reprogram your epigenome.
Let me repeat: even if you’ve only made poor health decisions for your entire life, and even if your mother and your grandmother made poor health choices, and even if you and your ancestors suffered adverse events that led to adverse epigenetic changes, you can improve your condition. Epigenetic reprogramming is a real and measurable thing that you can use right now.
The best way to know what’s moving the needle in shifting to a health-promoting epigenetic profile is to work with a qualified professional who can understand the moving pieces of your genetic markers, epigenetic clock, blood tests, and other biomarkers to fast-track you to a long life of vibrant health.
The second best way is to get some key biomarker tests on your own and test what works for you and what doesn’t. There are some basics everyone can apply, and I encourage you to look at all of the Foundations posts on this site for guidance. Expect to include nutrient-dense whole foods, an active lifestyle, deep restorative sleep, and a mindset practice to decrease stress and keep you looking forward in your life.
References:
de Toro-Martín, J., Guénard, F., Tchernof, A., Hould, F.-S., Lebel, S., Julien, F., Marceau, S., & Vohl, M.-C. (2019). Body mass index is associated with epigenetic age acceleration in the visceral adipose tissue of subjects with severe obesity. Clinical Epigenetics, 11(1), 172. https://doi.org/10.1186/s13148-019-0754-6
Martínez, J. A., Milagro, F. I., Claycombe, K. J., & Schalinske, K. L. (2014). Epigenetics in adipose tissue, obesity, weight loss, and diabetes. Advances in Nutrition, 5(1), 71–81. https://doi.org/10.3945/an.113.004705
Pigeyre, M., Yazdi, F. T., Kaur, Y., & Meyre, D. (2016). Recent progress in genetics, epigenetics and metagenomics unveils the pathophysiology of human obesity. Clinical Science, 130(12), 943–986. https://doi.org/10.1042/CS20160136