You are holding a book about aging and death written by someone who wishes not to age or die. I hope that you share this sentiment and that we have a common goal, but I know that reality isn’t always what we want it to be. Death is not easy to overcome, and odds are my reader is skeptical that lifespan can or should be extended indefinitely.

In a recent study published in the Journal of Aging Studies, only a third of survey subjects (American adults) were sure of a desire to take an immortality pill if one were created. Forty-two percent would not take the pill, and twenty-five percent were unsure. This is not surprising given that modern culture often portrays the desire for everlasting life as sinful or even villainous, and with regrettable consequences. In Oscar Wilde’s The Picture of Dorian Gray the pursuit of eternal youth drives the main character to cruelty and murder. A similar idea is portrayed in the TV series Altered Carbon, in which the wealthy and immortal “Meths” indulge in torture, rape, and the killing of women and children to satisfy their sexual perversions—a manifestation of the state of ultimate boredom they have reached after trying everything else. And in James Cameron’s Avatar: The Way of Water we are presented with evil members of the human species who hunt down magnificent sentient sea creatures to extract amrita (the word means immortality in Sanskrit)—a yellow liquid that is said to have anti-aging properties.

The immortality of Lord Voldemort comes from Horcruxes that can be created only by committing murder. The dark wizard is reminiscent of Koschei the Deathless, an archetypal evil sorcerer of Slavic folklore who also hid his immortality in a physical object—a needle within an egg. This incidentally foreshadowed the invention of cloning techniques, which are frequently featured in dystopian fiction revolving around organ harvesting for life extension; such fiction includes Kazuo Ishiguro’s novel Never Let Me Go and Michael Bay’s film The Island.

The moral issues with eternal life depicted in these stories are not in immortality itself, but in the desire and “unnatural” methods employed to achieve or maintain it. Benevolent long-living fictional characters, such as the Doctor (Doctor Who) and Gandalf (The Lord of the Rings), exist but they typically receive their life extension naturally, without actively wanting it or doing anything special in exchange for it. For some characters, such as Deadpool, immortality is even undesirable, a problem that they can do nothing to solve. The half-elven Arwen (The Lord of the Rings) chooses human mortality in order to be with her beloved Aragorn, while Nicolas Flamel (Harry Potter) voluntarily relinquishes his and his wife’s life source—the philosopher’s stone—in what is presented as a favorable turn of events. Dumbledore later explains to Harry Potter, “To one as young as you, I’m sure it seems incredible, but to Nicolas and Perenelle, it really is like going to bed after a very, very long day. After all, to the well-organized mind, death is but the next great adventure.”

I’m surprised by humanity’s capacity to find optimism about death given how much we have to lose: not just our own personal existence, but the lives and well-being of our loved ones. I can understand such optimism in a person who wholeheartedly believes in an afterlife, but even atheists sometimes display this attitude. Allow me to quote the evolutionary biologist Richard Dawkins, who has rated his atheism as a six out of seven: “We are going to die, and that makes us the lucky ones. Most people are never going to die because they are never going to be born. The potential people who could have been here in my place but who will in fact never see the light of day outnumber the sand grains of Arabia.”

The respected scientist is in good company, including such intellectuals as Mark Twain, who wrote, “I do not fear death. I had been dead for billions and billions of years before I was born, and had not suffered the slightest inconvenience from it,” and Michel de Montaigne: “To lament that we shall not be alive a hundred years hence is the same folly as to be sorry we were not alive a hundred years ago.” These are all variations of the argument made by the ancient Greek philosopher Epicurus: “Death is nothing to us. When we exist, death is not; and when death exists, we are not.”

I have never understood these intellectual gymnastics, poetic though they may be. My opinion is that they undervalue life and present multiple ethical and logical contradictions. Should we relate the decision to remain child-free, or to use contraception, to serial murder, as such a decision leads to the nonexistence of potential people? Is murder as big a deal as most human societies perceive it to be? Is overpopulation a good thing, and should we strive for it? Do we expect parents to grieve the nonexistence of all their theoretically possible children as much as the death of their actual child? If death truly doesn’t concern us and the fear of death is folly, should we give up on improving medical science? Do fearless optimists hold their spoken beliefs sincerely? That is to ask, are they truly indifferent to whether they live or die? If nonexistence doesn’t concern them, why do they struggle to live? And if religion proscribes leaving the world voluntarily, should one seek Biblical loopholes, such as reckless self-endangerment by balancing a unicycle on a rope over a pool of sharks to “speed run” to the afterlife?

It is as if humanity suffers from a Stockholm syndrome for the Grim Reaper, as even our best minds must try to cope as his hostages. We don’t want to view death as something horrible because negative attitudes make us feel uncomfortable, and we believe that we can’t solve the problem of death in any case. In a commencement speech at Stanford University Steve Jobs went as far as to conclude that “death is very likely the single best invention of life. It is life’s change agent. It clears out the old to make way for the new.” This compliment to death came right after the entrepreneur accepted death as unavoidable: “No one wants to die. Even people who want to go to heaven don’t want to die to get there. And yet death is the destination we all share. No one has ever escaped it.”

Here I would like to draw a parallel with the TV series From, in which a group of people are unable to leave a mystical town full of bloodthirsty monsters that come out at night. After an incident involving multiple deaths, several survivors decide to build a radio tower to attempt to contact the outside world. This angers one of the group’s leaders. Later she explains her feelings: “I am grieving the fact that you guys are so caught up in playing Mr. Fucking Wizard that you can’t see what this place is gonna become when you fail.” Perhaps some of us look down on those who work on radical life extension because we don’t expect them to succeed and we are scared of losing hope.

But aging is trickier than most make-believe monsters. It deteriorates us relatively slowly, relaxing us into a false sense of security—less like The Texas Chainsaw Massacre and more like The Horribly Slow Murderer with the Extremely Inefficient Weapon. As fiction writer Neil Geiman famously wrote: “I used to think [death] was a big, sudden thing, like a huge owl that would swoop down out of the night and carry you off. I don’t anymore. I think it’s a slow thing. Like a thief who comes to your house day after day, taking a little thing here and a little thing there, and one day you walk round your house and there’s nothing there to keep you, nothing to make you want to stay. And then you lie down and shut up forever. Lots of little deaths until the last big one.”

To break this illusion I suggest watching the scene in Indiana Jones and the Last Crusade in which Walter Donovan, the Nazi ally who drinks from a false Holy Grail in an attempt to achieve eternal life, ages and dies in a matter of seconds. The screams of his colleague Dr. Elsa Schneider seem to me like an appropriate reaction to the horror of aging and dying.

So instead of coming to terms with our demise and repeating This is fine as we watch the people we love turn into ashes, I suggest that we turn to science, a human enterprise with a history of achieving things once deemed impossible, such as curing previously intractable diseases, creating global webs of knowledge, and landing people on the moon. Let’s get informed about why we age and why we die and see if there is any hope that we can do something about it. Perhaps there is a solution to be found. After all, in humanity’s long history, we have overcome many disasters, plagues, harsh environments, and other deadly challenges. Aging is just another problem.

Let me inspire a modest amount of hope. Our lives have already been extended.

Thanks to recent advances in infrastructure, science and medicine, we now live, on average, twice as long as our ancestors of only two centuries ago. This is true not just in the wealthiest countries, but all around the globe. And there is no indication that this trend is likely to stop. Japan, Singapore, Australia, Iceland, Italy, Norway, Macao, Malta, Israel, South Korea, Ireland, New Zealand, and Switzerland—all of these countries have already achieved average life expectancies exceeding eighty years for both men and women, and many countries are catching up.

It is true that one important contributor to the doubling of the average human life expectancy since the nineteenth century is the decrease of child mortality. However, the rate of deaths related to older age has also diminished. In socio-economically developed countries, the average age of death in those who have lived at least sixty-five years increased by approximately three years every twenty-five years between 1960 and 2010. If this trend continues, adults can expect to live about six more years than their grandparents, but given that science is advancing at an ever-increasing pace, this number may be a severe underestimate. Meanwhile, the biological evolution of our species has also made significant contributions to our longevity over the last several million years. The maximum lifespan of our closest relatives (chimpanzees and gorillas) doesn’t exceed seventy years, while our species’ record is around 120. This implies that the rate of human aging is not fixed. We just need to figure out how to slow it down.

Today we know more about aging and age-related diseases than ever before: over forty thousand scientific articles related to this topic were published in 2023 alone, almost twice as many as ten years before. When I decided to study bioengineering and bioinformatics at my university I was deeply inspired by an experiment that doubled the lifespan of a roundworm called Caenorhabditis elegans with the help of gene editing. By the time of my graduation, researchers had already achieved a tenfold increase in the median and maximum adult lifespan for this worm species. As for mammals such as mice, lifespan increases of twenty, thirty, forty, fifty, and even sixty-five percent have been achieved with interventions targeting various elements of the aging process. As I will explain in detail in further chapters, we have reasons to expect that some combinations of these interventions might be even more beneficial.

Other good news includes the discovery of animals that age minimally, such as the hydra, the “immortal” jellyfish Turritopsis dohrnii, and naked mole-rats, with their remarkable resilience to cancer and other age-related disorders. Orville Wright said, “If birds can glide for long periods of time, then . . . why can't I?” Rephrasing this famous quote, a biologist could ask, “If a hydra can live without aging . . . why can’t I?” It appears that aging is not a necessary property of living organisms, and thus, fixing the problem of aging shouldn’t violate any laws of nature.

On this matter Richard Feynman, a Nobel laureate in Physics wrote: "It is one of the most remarkable things that in all of the biological sciences there is no clue as to the necessity of death. If you say we want to make perpetual motion, we have discovered enough laws as we studied physics to see that it is either absolutely impossible or else the laws are wrong. But there is nothing in biology yet found that indicates the inevitability of death. This suggests to me that it is not at all inevitable, and that it is only a matter of time before the biologists discover what it is that is causing us the trouble and that that terrible universal disease or temporariness of the human’s body will be cured.”

In fact, even humanity carries a hint of immortality. Although our bodies age, every one of us descends from an ancient line of cells, the immortal germ line that has undergone countless divisions for billions of years. In 2012 Shinya Yamanaka was awarded a Nobel Prize in Physiology or Medicine for finding a set of genetic factors that are capable of returning the aged specialized cells of our body to immaturity, restoring their potential to multiply and develop into any type of cell. This technology is one of many harbingers of future developments in cell, tissue, and organ rejuvenation. Or think of it this way: if some axolotl can regenerate lost limbs and even parts of the brain . . . why can’t I?

Promising therapies targeting the diverse mechanisms of aging have been invented, and tested on animal models. We can remove old and damaged cells, induce the processing of damaged cellular components, and reduce DNA damage to promote longevity. Never in history have we had such an impressive arsenal of anti-aging instruments, with gene therapy at its pinnacle. Not only can we insert beneficial genes into our cells’ DNA or edit existing genes, but we can select which cell types to affect, and even program the conditions under which inserted genes should work, with adjustable on and off switches regulated by pharmaceuticals, temperature or even light. Dozens of genes linked to lifespan are known, and one strategy for radical life extension could involve changing their activity in the right cells at the right time.

As we search for solutions, it is important not to get ahead of ourselves. Unfortunately, “false Holy Grails” are very real, and the topic of life extension is accompanied by “fake news” and speculation. Such false Grails include promises of human immortality looming in the next decade and of miraculous cures around the corner. While no proven treatment for human aging exists, “biohacking” approaches based on weak or absent evidence are becoming an easy but misleading sell. These range from things vaguely resembling science to such obvious pseudoscience as fancy magnets and crystals for one’s chakras. It’s in our best interest to discern between well-established science of aging, plausible hypotheses that require investigation, and nonsense. To succeed in our endeavor we should strive towards an objective scientific understanding of aging. Our very lives depend on getting the science right.

Proper research takes time, and unfortunately we are spending this valuable resource unwisely, as society is hardly doing enough. It feels that many people still need to be convinced that death is an enemy worth fighting. Existing negative attitudes toward lifespan extension are at least partially a consequence of an erroneous cultural association between long lifespan and long-term frailty. Many fear the unpleasant thought of living forever in a nonfunctional body that requires constant maintenance. However, when mental and physical health is guaranteed, about eighty percent of poll respondents wish to live to be 120 years old or older, and fifty-three percent desire an infinite lifespan—much more than in scenarios where only mental or only physical youth is guaranteed.

Thus, it is important to explain that deathless frailty is a self-contradiction, due to the relationship between aging and dying. Currently, as we age, the probability of our death doubles about every eight years. The older you are, the more likely you are to be diagnosed with cancer or cardiovascular disease, or to die from an infection or because of an accident. Some demographic research suggests that mortality reaches a plateau after about 105 years, but this is likely a result of selection bias: average people have already died, while the very few genetically healthiest people with lower baseline mortality rates are still alive, distorting the trend.

The deadly impact of aging is best demonstrated by a simple thought experiment first presented to me by my friend and colleague Alexander Tyshkovskiy, who studies gerontology—the science of aging—at Harvard Medical School. Imagine that one could stop aging at thirty. How long would a thirty-year-old person live under current normal conditions? Make an intuitive guess before reading further; perhaps the answer will surprise you.

In developed countries the average mortality rate for people in this age group is currently around one death per one thousand people per year, which equates to a 99.9 percent probability of surviving a given year. On average, a non-aging thirty-year-old would live one thousand years before dying of non-age-related causes. The math becomes even more intriguing if we account for the sex difference in mortality rates. In our thought experiment, men would live, on average, 650 years, compared to 1650 years for women. Imagine the social implications.

Since aging is the most significant underlying cause of human death, any hypothetical radical life-extension treatment has to prolong youthfulness. And that is exactly what we see in animal models, where most anti-aging approaches not only extend lifespan, but delay physical and cognitive decline. The same can be said about humans: existing supercentenarians (people who are more than 110 years old) experience a delayed onset of cancer, cardiovascular diseases, dementia, and other age-related disorders. Conversely, if somehow we invented ways to increase our healthspan, most likely our life expectancy would also increase.

Some fear that dramatically extended lifespan would lead to problems such as overcrowding and increased social inequality. While the details of a technologically advanced future are difficult to predict, increased lifespan would not necessarily lead to population growth. Moreover, countries with higher life expectancies tend to have lower birth rates. There are several potential explanations for this. When mortality rates are especially high, having more children becomes a necessity to ensure that at least some of them survive. People also adjust their reproduction timing based on their own longevity and quality-of-life expectations. Why have kids now, when you have time and resources to get an education, form a career, and travel first?

But there is an even better counterargument to assumptions about overpopulation. The intuitive idea that a population of reproducing immortal beings will grow indefinitely until complete ecological collapse contradicts simple mathematics. As long as parents produce fewer than two children on average, each next generation will be smaller than the previous one, and a final limit to population size will be reached. This limit is equal to N / (1-r), where N is the current population size and r is the ratio between subsequent and previous generation sizes, with a value between 0 and 1. In a situation where every pair of parents has one child on average, r would equal 0.5. Thus, no matter how much time passes, no more than double the initial population size will occur, because the mathematical limit of the series 1N + 1/2N + 1/4N + 1/8N + 1/16N . . . is 2N. This is under the extremely unrealistic scenario of humanity not only defeating aging but somehow removing all causes of death and every single living person deciding to live forever. Even in such a scenario as this, an immortal society can preserve the joy of parenting without unsustainable population growth.

Another observation is that, while the fear of overpopulation is a common theme in discussions about radical life extension, support for campaigns to limit human reproduction is usually low. Perhaps the overpopulation argument comes up not because we truly fear outgrowing our ecosystem, but because we want an excuse for inaction. If immortality is framed as something bad, then we are doing a good thing by doing nothing.

If radical lifespan extension is achieved, I believe we must do whatever is necessary to ensure that it becomes available for all who desire it. From a technological standpoint there is nothing preventing this possibility. Even the most advanced technologies have a history of becoming quickly available to the majority of people. This happened with cell phones, as it happened with modern vaccines created with the use of sophisticated genetic engineering. Given that gene therapies are among the most promising candidates for anti-aging interventions, and that their manufacturing costs can be reduced to those of vaccines, it’s not difficult to imagine a future where almost everyone has the opportunity to prolong their lifespan, regardless of their income. Everyone should have the choice to prolong their life, and the option to resume aging if they ever change their mind.

Fears of immortal dictators or wealthy elites prolonging their reigns should encourage us to better organize our societies and fight inequality, not prevent progress from benefiting all humankind. After all, tyranny can outlive the tyrant, and the prevention of scientific advancement is not a solution to this problem. Moreover, it is possible that tyrants will be overthrown faster if we stop waiting for natural concessions of power.

But in my opinion one of the best arguments against most objections to radical life extension was presented in Andrew Steele’s book, Ageless: The New Science of Getting Older Without Getting Old. Imagine that humanity has become immortal and is facing some social or ecological problem. Would reintroducing aging be a proper and ethical solution? As Andrew Steele writes, “Would creating aging and condemning billions to suffering and death be a viable answer to climate change, or global overuse of resources? Surely we’d find other ways to reduce our collective footprint on the planet before resorting to such barbarism. Similarly, invoking aging to limit the reign of even a particularly despotic ruler is a plan which goes far beyond the craziest CIA assassination plots. Looking at this this way around, the answer is clear: aging isn’t a morally acceptable solution to any serious problem.” I agree that the idea of reintroducing aging, a process that would kill everyone in existence, does feel more sinister than the grand scheme of the antihero Thanos, who wanted to kill only half of all sentient beings. So shouldn’t the removal of aging be considered an act of good?

Although it is important to discuss the potential social and moral issues of radical life extension, we should not forget that if we die, there will be no social issues for us to concern ourselves with. Some people say that life without death is meaningless. But on this subject I would rather agree with Jean-Paul Sartre: “death is never that which gives life its meanings; it is, on the contrary, that which on principle removes all meaning from life. If we must die, then our life has no meaning because its problems receive no solution and because the very meaning of the problems remains undetermined.”

Not war, not plague, not famine, but aging is the main cause of human death. That is why the main focus of this book lies in biological explanations of aging and the tools we need to work against it. This is not a simple task, but as Eren Yeager (Attack on Titan) once proclaimed: “If you win, you live. If you lose, you die. If you don’t fight, you can’t win.”

While this popular-science book is for readers of any background, I must warn you that a number of rather difficult concepts from the field of molecular biology will be introduced and explained to the best of my ability. I have found that discussions of aging provide remarkable opportunities to appreciate the brilliance and diversity of life, with all the sophisticated molecular machinery and complex pathways that allow living organisms to thrive on our planet. Also the book is illustrated by a talented artist Olga Posuh. Some drawings are informative and inspired by modern biological research, while others are metaphorical visual summaries of the included chapters. Together they form a story about life prevailing over death for your esthetical enjoyment.

Speaking of art, I usually end my popular-science lectures on the topic of aging by presenting a 1562 painting by Pieter Bruegel the Elder called The Triumph of Death. For me, the depicted scene of suffering is a ghastly reminder that humanity has been squandering its precious time and resources on wars and struggles for power. What we should have been doing all along is cooperating, and dealing with the greatest and most imminent danger. Perhaps together we can finally put an end to the Triumph of Death.