By Mukaila Kareem
In the ever-renewing rhythm of biological life, immortality is a myth known only to dreamers and vitamin salesmen. From the simplest bacteria to the most complex human beings, one truth remains etched in every strand of DNA: all living things are terminal. If you want to understand why the “don’t die” movement is fundamentally flawed, just ask a cell.
From the earliest and still most prolific life forms on Earth, unicellular organisms don’t fear death. They divide rapidly to reproduce by creating clones of themselves. However, when their environment shifts against them, they mutate just enough to pass on survival advantages to the next generations. Their strategy isn’t to live forever but to propagate strategically within their short lifespans. Therefore, to a bacterium and other unicellular organisms, the game is not longevity but continuity.
In sharp contrast are the cells in multicellular organisms like humans. These cells also divide, but not to become independent organisms. Instead, they divide for growth, repair, and maintenance. These are processes needed to replace injured cells, replenish tissues, and support the overall survival of the organism. Therefore, every second, millions of cells are dividing, not to make new humans but to uphold the integrity of tissues, organs and physiological systems.
If cells operated on an eternal biological clock, this machinery of renewal would be redundant. But they are not. Human cells have a distinct, genetically programmed lifespan ceiling. For example, red blood cells last about 120 days, and the skin cells may last a couple of weeks. Neurons, the cells that make up our nervous system, can live for decades but they are not immortal too. There is no master cell in the body that escapes this biological clock. Therefore, no tech, no tonic, and no testosterone booster that can change this mortality reality.
The truth is that our bodies undergo cellular cloning nonstop, simply to stay alive. Cloning is not optional but essential. Without it, healing and growth would never happen. If cells were eternal biological clock, this machinery of constant renewal would be redundant. But even a red blood cell “born” today knows it’s on borrowed time and on a three-month countdown to death.
This is no longer an abstract theory for me. In just under a year, I’ve been reminded twice—painfully and personally—that Late Nnamdi Azikiwe’s words still ring true: “No condition is permanent.” Eleven months ago, I lost my cousin who was my twin in many ways. We were raised together by our uncle and were just three months apart in age. We shared a childhood, attended the same high school, and even went to the same university. From our preteen years to young adulthood, our continuous bond only deepened. Even into middle age, that connection remained stronger than ever, and his passing left a crater I am still navigating.
Yesterday, July 26th, 2025, the mortality struck again. Exactly nine minutes before finishing my usual 60-minute brisk walk in the gym, I received a message that my half-brother had just passed less than three minutes earlier. I was stunned. Though we never lived together for more than a year at a stretch, he was someone I deeply respected. Having been raised in a traditional home, I would say he was at least six years older and one of those older relatives I looked up to. Kind, wise, warm-hearted and always with a big smile. A Yoruba proverb says, “The good trees don’t last long in the forest.” How devastatingly true.
And yet, despite these raw reminders of impermanence, we live in a time when humans are being sold the illusion of control over mortality. The so-called “longevity experts,” many of whom are just rebranded diet warriors from decades past, are offering fasting hacks, supplements, and IV drips as if they can override the code of life. But here is the obvious and a challenge: if you can’t extend the average height of a human being by seven inches, you’re not going to extend the human lifespan by seventy years.
Why the challenge? Because average adult height is a biological outcome of nutrition, hormones, cell proliferation, and the so-called tissue remodeling that are limited by genetic ceilings. If we can’t hack height despite generations of access to food, health care, and data tracking, then perhaps our lifespan is similarly bound by evolutionary and biochemical realities.
For context, the longest-lived person on record remains Jeanne Calment of France, who died in 1997 at the age of 122. That record has stood longer than any of the supplements promising to beat it. Not one medical breakthrough in the form of organ transplants, stem cell therapies, CRISPR editing, or AI-driven diagnostics has extended that bar. And whales are doing just fine without annual veterinary checkups living over 200 years in the deep sea based on their genetic ceiling.
Ironically, humans fear death in the exact same way our cells don’t. Every cell prefers to live but also “knows” when to die. Programmed cell death, or apoptosis, sometimes called self-suicide, is a built-in feature of survival. Without it, we wouldn’t hollow out the abdominal or thoracic space or grow fingers in the womb or avoid cancer in adulthood. Cells don’t fear mortality, but they manage it. This biological wisdom has been hijacked by marketing: enter the vitamin pushers, peptide promoters, and cold-plunge crusaders. Their message isn’t new but just rewrapped in fear. They target the same primal vulnerability that made ancient humans seek the fountain of youth—the desire to not die.
The truth is this: we can reduce suffering, and we can improve healthspan. However, what we cannot do and what we should not pretend to be doing is to promise mortality escape. The cells already know this and so do the good trees in the forest. It’s time we caught up!
Everyday we are all on countdown to the mortality date. Adieu my dear cousin, Amos Kehinde. Adieu my brother, Isiaka Kareem.
Mukaila Kareem, a doctor of physiotherapy and physical therapy advocate, writes from the USA and can be reached via makkareem5@gmail.com
