The 9 Known Causes of Aging and How We Might Influence Them
Sample chapter of Healthspan Mastery: Why aging happens, what goes wrong beneath the surface, and what we might do to support our health and wellness
I also offer this post for my readers on Medium.
We all age. That is one certainty life guarantees. Although we cannot stop the clock, we can influence how gracefully we age through our lifestyle, where we live, and the tools we choose to support our health. In other words, healthy lifestyle choices, environmental changes, medical enhancements, and pharmaceutical interventions can help.
In the modern world, the “Four Horsemen of the Medical Apocalypse” cardiovascular disease, cancer, neurodegenerative disease, and metabolic disease continue to affect millions of lives each year, more prevalent among the aging population.
In this chapter of the Healthspan Mastery, I will explain nine well-established causes of aging, which scientists and clinicians refer to as “hallmarks of aging.” These are not abstract ideas or mystical processes. They are tangible and observable mechanisms in our cells, well-documented and replicated in the scientific literature.
Advanced researchers worldwide, particularly in fields such as molecular biology and biogerontology, have mapped them out in surprising detail, giving us valuable clues.
The most credible and comprehensive source has been a seminal paper published in Cell in 2013. However, over the last decade, we have gained more knowledge, and many excellent papers have been published, offering us new insights. I will cover them in my upcoming book, Healthspan Mastery, which is scheduled for release in 2026.
Despite many rigorous scientific studies, including those with Nobel-winning ideas, the mystery of aging remains far from solved. We still have a lot to discover, and I remain optimistic about finding them with the power of science and emerging technologies.
What we know so far provides valuable clues, not to reverse aging in a fantasy-like way, but to live better (healthspan) and possibly longer (lifespan) by understanding what happens beneath the surface of our skin. Anti-aging is not feasible based on our current knowledge.
The more I read about cellular processes in new studies, the more I notice how adaptable our cells, tissues, organs, and systems are. They respond to stress, heal from injuries, and correct many of their own errors when given a chance.
Aging, in this view, goes beyond focusing on decay. It also involves how well we respond to stressors, how well we manage damage, repair mistakes, and maintain balance over time. I want to summarize these nine hallmarks as windows into the intelligence of our cells to give you valuable perspectives.
1. Genomic Instability: When DNA Repair Falls Behind
Every day, each cell in your body faces small attacks from sunlight, pollution, chemicals in food, and even the act of breathing. These attacks can damage DNA.
Fortunately, our cells are equipped with repair tools. They identify a broken segment, clip it out, and patch it up.
However, like any system, this repair machinery can eventually wear out. When the damage accumulates faster than it can be repaired, errors persist. Over time, this instability can affect how genes work, how cells divide, and how tissues age.
In young organisms, this process is usually well-balanced. However, with age, the errors become more frequent, and their consequences become more visible, including mutations, faulty proteins, and cellular confusion.
This is not necessarily a straight line to disease, but it does create a more fragile environment.
Some researchers are exploring ways to support these repair systems. Specific nutrients, fasting routines, or reduced exposure to known toxins might help the body stay ahead in the repair game.
But nothing replaces the foundational idea: the less chronic stress our cells face, the better they seem to maintain their genetic blueprint. In a recent story, I explained the mechanism through a groundbreaking paper published in Nature in May 2025
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2. Telomere Attrition: The Countdown of Cell Division
Telomeres are the protective ends of chromosomes. You might think of them as the plastic tips on shoelaces. Without them, the ends unravel.
Each time a cell divides, the telomeres shorten. Eventually, they become too short to protect the DNA, and the cell can no longer divide safely.
This shortening is a natural part of the process. It is one reason why most cells do not live forever. In a way, telomeres help protect us from cancer by preventing aged or damaged cells from dividing. But at the same time, when too many cells reach this point, the tissues they make up begin to weaken.
Some studies suggest that our habits influence the rate of telomere loss. Chronic stress, for instance, appears to accelerate it.
On the other hand, restful sleep, social connection, and specific dietary patterns appear to support telomere health. There is no guaranteed solution, but understanding that our choices might slow the countdown is a compelling idea.
I wrote a specific article about telomeres last year, which might provide you with more nuanced guidance.
How to Look After Our Telomeres for a Healthier and Longer Life
According to scientific studies, longer telomeres might result in a healthier, happier, and extended life if we address…
3. Epigenetic Alterations: When the Instructions Get Rewritten
DNA is described as the blueprint of life, but blueprints are not helpful without instructions on how to read them.
That is where epigenetics comes in. It tells our cells which genes to activate and which to suppress, and when to do so. Over time, these instructions shift, not randomly, but not always helpfully either.
In aging, we see growing evidence of epigenetic drift. Genes that should remain inactive become active, while essential genes may lose their function. This misregulation can lead to loss of identity in cells and trigger inflammation, faulty repair, or even uncontrolled growth.
The exciting part is that epigenetic changes are influenced by behavior. They are not set in stone.
Some researchers believe that diet, physical activity, sleep, and psychological well-being leave epigenetic marks. For example, meditation, which alters the cortical thickness of the brain, can have epigenetic effects.
Here’s How Meditation Can Impact Our Genes and Neurotransmitters.
Epigenetic, neurological, and hormonal effects of mindfulness practices on cognitive health based on scientific studies.
Our daily rhythm matters more than we thought, not because it adds years (lifepan), but because it may preserve the internal harmony of how our genes are read (healthspan). I explained the difference between genetics and epigenetics before.
4. Loss of Proteostasis: The Trouble with Broken Proteins
Proteins do most of the work in cells. They carry signals, build structures, and catalyze reactions.
However, for a protein to function correctly, it must fold into the correct shape. Aging disrupts this process. Damaged or misfolded proteins accumulate, especially when cleanup systems, such as autophagy, mitophagy, or the proteasome, become impaired.
A proteasome is a protein complex that breaks down damaged or unneeded proteins, helping maintain cellular health by regulating and recycling proteins through proteolysis.
Imagine a factory where defective parts begin to accumulate on the floor. Eventually, the machines come to a standstill, and production halts. In cells, this can lead to dysfunction or even cell death. It is one of the reasons neurodegenerative diseases often appear later in life.
Scientists are investigating how autophagy, our internal waste-removal system, might be reactivated. Several fasting strategies, like intermittent and periodic fasting, heat and cold therapy, and nutritional biochemistry compounds, are currently under investigation. Again, the focus is not on reversing aging, but on helping cells clean house more effectively.
5. Deregulated Nutrient Sensing: The Body Forgets How to Listen
Cells constantly listen to their environment. They sense the availability of sugar, fat, or amino acids and adjust their metabolism accordingly.
This system, regulated by pathways such as insulin and mTOR/AMPK, maintains the body's balance. But aging tends to confuse the signals. Cells may act as if they are starving when nutrients are plenty, or the other way around.
This confusion can lead to insulin resistance, weight gain, and chronic inflammation. It also slows down the body’s ability to adapt to change, a crucial aspect of remaining resilient with age.
Some researchers believe that the timing and quality of food, not just the quantity, can restore more explicit signaling.
Time-restricted eating patterns and metabolic flexibility through different food groups are active areas of study. The idea is not to restrict, but to recalibrate so that cells can remember how to listen again.
For example, I recently wrote about a nutrient, Stearic Acid, and how mitochondria sense it more than other lipid-based nutrients.
Astonishing Effects of Stearic Acid on Mitochondrial Health
I offer a summary of a sample chapter from the upcoming book, Cellular Intelligence, to provide readers with insight…
6. Mitochondrial Dysfunction: Power Outages at the Cellular Level
Mitochondria are the energy centers of cells, and they also serve as signalling molecules for our metabolism.
Mitochondria convert food into usable energy, much like batteries. As we age, mitochondria become less efficient. They produce less energy, give wrong signals, and release more free radicals, reactive molecules that can damage cells.
This decline shows up as fatigue, brain fog, and slower recovery. But it is more than just a drop in energy. Damaged mitochondria can trigger signals that cause inflammation and even prompt cells to undergo early death.
There is growing interest in how to support mitochondrial renewal. Movement, which is exceptionally brief and intense, appears to stimulate the formation of new mitochondria.
Specific nutrients and temperature shifts (both hot and cold) may also provide mild stressors that encourage mitochondrial adaptability. Again, these are not fixes, but signals inviting the body to strengthen its systems.
I cover mitochondria in my upcoming book Cellular Intelligence, which I introduced recently in multiple stories:
How an Inventive Lucid Dream Inspired Me to Write a New Book About Mitochondria: Welcome to Cellular Intelligence, which will be a gift to society on 1 January 2026.
7. Cellular Senescence: Cells That Quit but Refuse to Leave
Sometimes cells stop dividing as a safety mechanism. This is called senescence. These cells are not dead, but they no longer function normally.
They release inflammatory molecules and disrupt the surrounding environment. It is like a retired worker who refuses to leave the office but continues to cause trouble.
In small numbers, senescent cells help prevent the formation of tumors. However, when they accumulate in tissues, they become harmful. Their secretions contribute to chronic inflammation and tissue breakdown.
Some experimental treatments aim to clear out these lingering cells. In the meantime, research suggests that lifestyle factors such as regular physical activity and stable blood sugar levels may influence the accumulation of these cells. Future therapies might target them directly, but our capabilities are limited.
8. Stem Cell Exhaustion: When the Repair Crews Slow Down
Stem cells are our body’s reserve force. They stay dormant until needed, then spring into action to repair tissues.
With age, these cells lose their capacity to divide and respond. As a result, recovery slows, regeneration weakens, and resilience declines.
This exhaustion is not sudden. It builds gradually. It not only involves injury repair but also everyday maintenance. Skin, blood, and immune cells rely on healthy stem cell pools to keep functioning smoothly.
Some evidence suggests that certain behaviors, such as adequate sleep, fasting, exposure to mild stressors (hormesis), and microtears in muscles, can protect or enhance stem cell function.
But we are still learning how these effects work in humans. What remains clear is that the body’s ability to rebuild is part of what keeps it young, and that preservation may matter more than replacement.
Stem cells are being pharmacologically used to treat certain health conditions, such as COVID-19.
9. Altered Intercellular Communication: Signals Crossed and Confused
Cells talk to each other using chemical signals. This conversation helps regulate the immune system, promote healing, and enhance overall coordination.
As we age, this communication becomes distorted. Inflammatory signals become louder, while repair messages grow faint.
This imbalance contributes to what some researchers refer to as “inflammaging,” a persistent, low-grade inflammation that affects nearly every system in the body. It weakens the immune system, disrupts sleep, and increases the risk of chronic illness.
While this field is still evolving, some possibilities are being studied, including gut health, vagus nerve tone, and even emotional well-being, which appear to influence how cells communicate.
It serves as a reminder that communication both within and outside the body is essential for maintaining coherence, responsiveness, and overall well-being.
Conclusions and Key Takeaways
The nine hallmarks of aging offer a map, not a verdict.
They help us understand what happens as time passes, but they also reveal how dynamic and responsive our cells can be.
Nothing in biology works in isolation. These hallmarks interact, reinforce, and sometimes counteract each other in fascinating ways.
What I find hopeful is that many of these mechanisms appear to be flexible. They may not be fully reversible at this stage, but they are not set in stone, either.
We cannot stop aging, but we can guide how we age gracefully by tuning in to the signals, reducing the metabolic and environmental noise, and supporting the quiet intelligence inside every cell.
Healthspan Mastery goes beyond hacks, supplements, anti-aging tricks, or rigid rules.
It is about sensible biohacking rooted in science and technology, refined through lived experience, and made accessible for real people in real lives, where human capabilities meet the edges of transhuman possibility, bringing us closer to realizing our full potential by evolving with intention and clarity.
After publishing Cortisol Clarity, Train Your Brain for a Healthier and Happier Life, and Cellular Intelligence, I received many heartfelt messages from loyal readers asking how to bring all these insights together and have a practical and holistic guide. I will include them in the Healthspan Mastery book and distill them for my subscribers in my new publication, Healthspan Mastery on Substack.
My goal is not to prescribe, dictate, or overwhelm. Instead, I want to offer you a clear and practical blueprint, a way to evaluate what works for your unique body, mind, and life phase. The Healthspan Mastery is not a sequel. It is a synthesis.
I aim to pass along what helped me reverse my own metabolic syndrome, reduce chronic inflammation, improve insulin sensitivity, enhance immune function, and restore mental clarity without relying on medications or surgery.
I also bring together what I have learned through anthropology, neurobiology, cognitive science, nutritional biochemistry, nutrigenomics, biotechnology, molecular biology, clinical research, and self-experimentation with neurobics to help you create your sustainable path to health, longevity, and happiness.
Thank you for reading my perspectives. I wish you a healthy and happy life.
This premium story was also published on my Health and Wellness Network, which is my community Substack publication curating content from healthcare professionals and researchers, which I also share with my readers on Medium.
Now I am working on an exciting project for health and wellness readers.
Introduction to Cellular Intelligence
Although I wrote this book for the general reader, I hope it inspires scientists and clinicians to refocus their attention on mitochondria as the foundation of healing.
We cannot continue to address surface symptoms without restoring cellular function. Lasting health begins deep inside the cell with the signal of mitochondria and genes.
You do not need a medical background to understand this book. If you are searching for mental clarity, emotional strength, or physical renewal, Cellular Intelligence will help you connect the dots.
My goal is to help you rediscover the power of your biology, beginning at the root, within the silent Intelligence of the trillions of cells that sustain your life, feeling, and being every single day.
If you are interested in being an alpha or beta reader, I will offer early access to this unique book at a 90% discount through my new discount shop. Please leave a comment on the story or contact me via this web form.
This small fee is not about profit but to ensure genuine commitment. In the past, many free readers downloaded my previous books but never shared any feedback.
That said, I remain deeply grateful to those who provided thoughtful input. It helped shape my writing, and I expect the same outcome in the early access of Cellular Intelligence, which will be a gift to society on 1st January 2026. I believe it will take me 7 months to refine it with SME input and beta reader reviews for public consumption.
Cellular Intelligence is a continuation of Cortisol Clarity and Train Your Brain for a Healthier and Happier Life, going into more granular details from energy to metabolic signalling.
Gaining cellular intelligence and understanding the role of mitochondria can also help you shed extra pounds and might help you live a healthier and happier life, making you feel younger as you get older, like me.
I wrote Cortisol Clarity to help readers learn about the complex nature of this hormone and provide valuable information to optimize it for a healthier and happier life. It is available in multiple bookstores and in my Health and Wellness Network newsletter as an educational source.
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