Does Chronic Stress Drive Cellular Aging?

Unfortunately, increasingly research emerges that points to the answer being YES, chronic stress causes early cellular aging. That’s the bad news. The good news is that there is a lot you can do about it. So much of your health is in your hands, and starts with the basics. So take a deep breath, close your eyes for thirty seconds and center, then read on.

What is cellular aging?

Cellular aging is the process of cells losing their ability to divide and repair. While they do not make new cells, they do remain metabolically active and can affect processes including chronic inflammation (which further promotes cellular aging). Another term for cellular aging is cellular senescence, which was historically considered a safeguard against processes like cancer (precancerous and cancerous cells contain a genetic mechanism that puts them into cellular senescence to prevent tumor growth). Recent scientific studies have demonstrated that conditions such as chronic stress and hormonal imbalance can also shunt cells into cellular senescence, and promote early cellular aging.

Young Cells Vs. Old Cells: What’s the Difference?

When we take a close look at cells, we see some clear differences between young cells and old cells. Young cells have very healthy, fully functional organelles (the tiny organs inside of them that perform jobs required for life), and stable, complete proteins. When we look at the organelles we see that a young cell contains healthy, fully functional mitochondria (mitochondria are the organelles or parts of a cell that are responsible for making energy and setting our metabolic rate). Mitochondria are extremely sensitive to damage. Any proteins or organelles that have been damaged can be quickly fixed or destroyed, minimizing inflammatory processes inside the cell.

In contrast, an older cell will have accumulated more damaged organelles, and more damaged proteins. That’s because an older cell can’t clear the damage as quickly. As this happens the inflammation level increases inside the cell, causing further damage to proteins and organelles. Mitochondria are especially susceptible to damage from inflammation, which impairs our cellular metabolic rate.


This damage also affects the cell’s DNA. Specifically, an older cell is more likely to have damaged DNA, and shortened telomeres. Telomeres, as we’ll see below, are important markers of a cell’s age.

What are Telomeres and How Do They Relate to Cellular Aging?

Telomeres are sections of DNA at the end of our chromosomes: they do not have genetic data that is copied when we make new cells, but they are still very important. Telomeres are little DNA buffers that protect our fragile DNA during replication, when we are making new cells. Every time our cells reproduce, we lose a chunk of telomeres. When telomeres reach a critically shortened length, the cell dies.

Telomeres can actually be measured and can tell us the age of our cells. This is important because our cellular age does not always correspond to our biological age. For example, an extremely stressed, overweight, physically inactive person with multiple chronic health conditions may be 40 years old biologically, but the age of her cells can be closer to 55-60 years (especially if excessive drinking, drug use, smoking, and/or poor diet are also factors). Conversely, a 60 year old woman who eats a light plant-based diet, avoids excessive alcohol and unhealthy foods, manages stress well, and avoids excessive sun exposure may have cells that are closer in age to the 40 year old woman.

How we care for our bodies shows up on and in our bodies, from the center of our cells outward.

Stress Hormones and Cellular Aging

Another study demonstrated the effects of cortisol responsivity and telomere shortening (a common measure of cellular age). This study, which consisted of 411 men and women aged 54 to 76 years and followed over 3 years, showed that people who were more responsive to cortisol levels in their body had shorter telomeres and were more apt to lose telomere length than people who did not respond as much to cortisol. Basically, this means that this study demonstrated that people whose cortisol levels increased as a response to a stressor also had shorter telomeres across the three year time period: “The difference in telomere attrition between cortisol responders and nonresponders corresponded to 107 base pairs on follow-up, indicating a difference of approximately 2 years in aging” (29).

So over the course of 3 years, they aged an average of five years, vs. their counterparts who released less cortisol as a response to an acute stressor.

Another study demonstrated that exposure of cells to hydrocortisone at levels that match the physiological cortisol levels seen in response to stress shuts down the enzyme telomerase, which repairs telomeres and prevents their shortening (and thus prevents early cellular aging). This study looked in particular at the effect of hydrocortisone on telomerase in immune cells, and its findings indicated that exposure to this stress hormone can impair immune activity over time.

Increasingly the effects of chronic stress are studied, and scientists are taking closer looks at how chronically elevated levels of stress hormones affect health on a cellular level. The following quote highlights the effects of chronically elevated stress hormone levels on health:

High levels of chronic stress are associated with numerous diseases and deleterious conditions, including obesity and abdominal fat deposition, metabolic syndrome, respiratory infection, immune compromise, cardiovascular disease, systemic inflammation, respiratory impairment, tumor growth, and dendritic shortening in the hippocampus and prefrontal cortex. Mouse models have demonstrated that catecholamine stimulation (simulating the hormonal effects of chronic stress) causes systemic damage to chromosomes. (1)

While it highlights what has been known for a while, it is also an indication of the increasing attention people pay to effects of stress hormone on a cellular level. Specifically, scientists are measuring with increasing frequency the effects of stress on our DNA, and especially on telomere length as it has been found to be a good marker of cellular aging.

Other Causes of Reduced Telomere Length, and Implications of Shortened Telomeres

Several other factors have been linked to reduced telomere length, including:

• Clinical Depression

• Anxiety disorders

• Obesity

• Smoking

• Physical inactivity

• Low social support

• Hostility

This quote highlights the link between shortened telomeres and chronic health conditions:

Recent studies have explored the relationship between telomere length and health and found short telomeres to be a risk factor for many diseases of aging, including cancer, cardio-metabolic dysfunction, and diabetes. (1)

OMG, What Can I Do About This?

So here is the beautiful thing about Functional Medicine: it starts with the basics, and is so simple that ANYONE who’s ready to make a change can do it. To start to reverse early cellular aging, especially that driven by chronic stress, there are some simple steps that have profound results.

• Practice Stress Management: I know, I know. Easier said than done. But it’s also critical to begin to reverse some of the early aging that occurs due to long term chronic stress exposure. The nice thing about this is that you now have a doctor TELLING you to start making time for self care, and for the things you love. Some women use exercise for stress reduction. Others may cook, practice better time boundaries, spend time with loved ones, meditate, go for massages, or do a host of other things. The important thing is to stop seeing self care and stress reduction as “something I’ll get to later,” and to start seeing it as “what I can’t afford to go without.”

• Eat a Healthy, Plant-Based Diet: getting lots of vitamins and minerals in your daily diet is critical for supporting overall health of your cells, as well as your adrenal glands. Our adrenal glands actually rely on healthy amounts of minerals and vitamins to be present in our bodies, and when these dip low, our adrenal glands interpret that as stress and answer the call with increasing levels of stress hormones. Same thing with eating an inflammatory diet: eating foods like low quality meats, sugar, processed foods, gluten and dairy, skyrockets the inflammation levels in our bodies which sounds the alarm for our adrenals to step in. How do our adrenals respond to high levels of inflammation? By increasing the amount of cortisol released (cortisol is closely related to hydrocortisone, the same cream you put over allergic rashes—a form of inflammation that shows up on your skin).

• Drink Enough Water: dehydration is a stressor. The whole body must work harder to do its job: your brain, your heart, your adrenal glands, everything. Drink filtered, clean water. Make some of it mineral water. Your whole body will love you for it.

• Sleep Well: restorative sleep shuts off the inflammatory cascade and reduces the burden on the adrenal glands. It also gives your cells time to clean out toxins and cellular debris, so that they can function more efficiently and repair damage done by inflammatory processes. Get enough sleep every night. Your whole body will thank you.

References:

https://www-ncbi-nlm-nih-gov.proxy.heal-wa.org/pmc/articles/PMC5590630/

https://www-ncbi-nlm-nih-gov.proxy.heal-wa.org/pmc/articles/PMC5460695/

https://www-ncbi-nlm-nih-gov.proxy.heal-wa.org/pmc/articles/PMC2386249/

https://www-ncbi-nlm-nih-gov.proxy.heal-wa.org/pmc/articles/PMC6450740/

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4678010/