Most of us think that DNA is something that cannot be changed. It is a fixed blueprint inherited from our parents that will last forever. However, studies of epigenetics reveal that certain behaviors or environments can change how genes work without changing the DNA sequence. Stress is one of these factors that can change how your cells read your DNA, affecting everything from your immunity to your brain health.

You might be wondering what the difference is between genetics and epigenetics. Genetics is the fixed DNA of your body, which you inherit from your parents. On the other hand, epigenetics chooses which genes to read and which genes to “turn off” during gene expression.

The Hypothalamic-Pituitary-Adrenal (HPA) Axis is crucial for stress management, as it creates a feedback loop of hormones to regulate the body’s stress reaction. When you encounter stress, the brain activates the HPA Axis, which releases cortisol. Some individuals may feel this reaction physically. Myla Yen (9) recounts, “When I am stressed, my face starts to heat up and become red. My heart also starts to beat faster.”

Cortisol is known as the “stress hormone.” It is released when an individual experiences short-term stress, long-term stress, or traumatic stress. Some advantages of cortisol are decreasing inflammation and regulating glucose and blood pressure. However, long periods of stress can be a disadvantage. The longer an individual is stressed, the more cortisol is produced. This leads to the effect of DNA Methylation, where the “off switch” becomes incapable of turning off by itself.

In DNA Methylation, methyl groups attach to the gene. These methyl groups change the way the DNA sequence is read. Essentially, they are the “stop signs” in the DNA sequence, silencing certain cells and preventing them from being read. When you are in chronic stress, the genes that are silenced are usually the genes that are supposed to benefit you.

For example, when the NR3C1 gene is silenced, it stops producing the Glucocorticoid Receptors, which are in charge of controlling inflammation. When these receptors “catch” cortisol, it signals to the body to stop the inflammation. In the short term, stress is anti-inflammatory; however, when a person experiences chronic stress, it can cause inflammation because there are no Glucocorticoid Receptors to manage the rising cortisol levels.

The impact of stress does not just affect the inner body. It can have physical effects such as the inability to focus or brain fog. When you are stressed, another gene that gets targeted is the Brain-Derived Neurotrophic Factor or BDNF. BDNF synthesizes new neurons and nerve cells in the brain. An increased number of neurons is connected to better memory and cognitive functions. If the BDNF is silenced, your brain is unable to create new neurons; therefore, your memory would be negatively affected. Brain fog and the inability to focus may also occur.

It may feel like once your gene is silenced, it might not return to normal. However, epigenetics is not permanent. Unlike DNA, epigenetics is reversible and can be changed. Some ways of reversing epigenetics include dieting, sleeping, and relaxing. Irene Kim (12) shared, “When I’m stressed, I usually do things that help me clear my head. Exercising, like playing tennis, going on hikes, or simply taking short walks, gives me a physical outlet and helps me reset mentally. Spending time with friends also helps a lot, whether that’s grabbing food, driving around, or doing anything that takes my mind off of school. I also love having chill moments to myself at home when I’m stressed, and I keep myself occupied by doing peaceful solo activities like baking, puzzles, and watching movies on Netflix.” These positive behaviors trigger enzymes that can erase the “stop signs” created by DNA Methylation, allowing all genes to be read during gene expression. 

Ultimately, you cannot change the genes you are born with. However, you have the power to decide how your genetic story is told through your environment and habits.