How long can a person live? The oldest human ever, at least that’s been confirmed, was Jeanne Calment, who lived to see 122. So that is literally as long as a human can live right now until someone gets older.
The average human lifespan is about 70 years but there are many factors that play into that all around the world including numerous diseases, malnutrition, war, and so many other things. Some geneticists believe 115 years is about all we could ever hope to get even under ideal circumstances, though Ms. Calment obviously spit in the eye of that idea.
These numbers are very much related to “natural” lifespan. But humans have a knack for taking nature and making it better (or worse). So, if we applied our brains, our technology, our science, what could we do? How long could a human live if we gave ourselves an assist? Would we ever have to die? Let’s find out!
How Do You Get to Be the Oldest Human Ever?
In 2025, the oldest living person in the world is Tomiko Itooka, who is 116 years old. She has a ways to go to catch up with Jeanne Calment. But how does anyone live so long? According to friends of Calment, she wasn’t just the winner of the genetic lottery, but you can bet that played an important part. She also had some other things going for her.
We won’t bury the lede on this one – Calment was rich. Rich people have a lot of advantages. She didn’t really work, she just socialized. She had a cook so she never even needed to think about what meals to make, and people did her shopping for her. She lived a life of leisure, by all accounts. She travelled the world, she saw the Eiffel Tower as it was being built, and she attended social functions. That’s not very stressful. And she took care of herself, because she had the time and the means.
In Japan, Ms. Itooka didn’t have as luxurious a life as Calment, but it sounded like a memorable one. In her younger years she was very active and was fond of hiking and climbing. In her 80s she even completed the Saigoku Kannon Pilgrimage which covers 33 different temples.
So let’s say, based on a very rudimentary reading of the lives of these two women, that longevity may be related to living a healthy, stress-free life. So simple!
Change in Lifespan
Human lifespan has evolved considerably over the years. Everyone has heard the anecdotal idea that the average human lifespan was only 30 years a hundred years ago (or 200 years, or whatever fits that narrative). While that is not wholly inaccurate, life expectancy for someone born in the year 1900 was only 32 years, it also misrepresents the data.
Average lifespans in the past were so low due to high infant mortality. If you live to 80 and your sibling died at birth then, between the two of you, the average lifespan was only 40 years. But, in reality, if you did survive to adulthood, then you probably lived a life not entirely different than you would in the modern world, at least in terms of duration. Most people survived well past 50. No one was elderly in their 20s.
Prior to 1900, 18% of children died before the age of 5. This was mostly due to infectious diseases, the sort of stuff we can vaccinate against now like measles and diphtheria. The infant mortality rate was around 10% and, in some cities, as much as 30%. That means 100 to 300 deaths per 1,000. In 2022, that number was 5.6 per 1000.
As infant mortality improved, thanks to things like better neonatal health, vaccines, nutrition and sanitation, overall lifespan increases. Battling other conditions like heart disease has also improved the life expectancy in most countries.
Covid took a big swing at global life expectancy and reversed almost a decade’s worth of progress. Numbers will probably go up again, globally, as long as trends continue the way they had been before the pandemic.
That said, if the growing antivax trend gets too much bigger, progress could be delayed or reversed even more. Vaccination rates dropped below 93% for some vaccines in 2022-2023. For 2024-2025 it’s likely the number will increase.
Charts showing the stunning success of vaccines when it comes to saving lives paint a very clear picture. Over half a million people per year got the measles before a vaccine. After? 13. By March 2025, the CDC had confirmed 222 cases in the United States. All of this is going to lower the natural lifespan of Americans moving forward.
Theories on How Long You Could Last
So if 122 years is the absolute best we’ve ever done, and in the last few years we’ve actually started backsliding because of poor decisions and novel diseases, what’s next? Can we hope for better?
To start with, it’s worth remembering that this all has to be speculation. Because, again, 122 years is the best anyone has ever done. And she did it without any help from cybernetic body parts, nanotechnology, altered genetics, or alien DNA. That said, there are experts in the field out there who believe a human can potentially live for a thousand years. Just try to imagine how much you would hate that.
João Pedro de Magalhães, a professor of molecular biogerontology, thinks we could wipe out aging on a cellular level based on his study of long-lived animals. If we do that, we could crack 1000 years. Or even something absurd like 20,000 years. What’s the science behind it? He doesn’t know. But he does believe we could invent it. Fair enough!
Others look at aging and death as two separate things that we wrongly link. Aging doesn’t lead to death, at least in the eyes of some. It’s just that the longer you live the more likely you are to die of something. So, theoretically, with improvements in medicine and technology, our life expectancy could continue to dramatically increase the way it did from the 1900s to now.
Of course, not everyone believes we can live forever. Some pick 120 to 150 as the range as the most we can ever hope for because disease and other hallmarks of aging will drag you down at that point no matter what you try. Bayesian statistical analysis has led some researchers to narrow it down further. The next “oldest” person in the world will likely make it between 125 and 132 years.
Striving for Immortality
Improvements in healthcare, medications, quality of life in general, are technically scientific advancements. But, when we ask could science help you live forever, is that really what we mean? No. You’re hoping for something much more dramatic.
When you think about science letting you live forever you’re thinking about genetic engineering or robotic body parts or something like that. Gerontologist Aubrey de Grey famously declared that the first person who will live to see 1,000 has already been born. So let’s look into the world of speculative science and see what it has in store for us.
We know there are creatures in the world that are functionally immortal right now. Something like the hydra comes to mind. This little life form is made out of stem cells so that it can keep renewing itself pretty much indefinitely. You can put a hydra in a blender, mulch it into a liquid, and the cells will reform into a living creature again.
Humans, however, are more complex. We can’t be only stem cells. If our cells constantly renewed like a hydra, we could not be complex life forms. Imagine if your neurons kept replacing themselves. Everything in your mind, your personality, your memory, all of it, would never form in the first place and if you ever did form something, it would vanish again as the cells regenerated.
Our cells have a limited time to them before they become senescent, which is to say worn out. Your cells do replicate, but only for so long. In time they just stop. They end up dying. You sort of grind down.
Some believe the key to getting past 120 years is nanobots. If our cells can repair themselves like those of a hydra, then we give them a helping hand. Microscopic robots in our bloodstream programmed to destroy cancer cells as they form, or repair red blood cells so they don’t break down.
Nanobots could maintain hormone levels, keep our brain functioning at peak levels, ensure organs never suffer any slowing or disease. They would, again in theory, eliminate anything that normal slows or limits a human body as it occurs.
If you are never slowed or never limited, then what could possibly kill you other than something sudden and out of your control? There would be no such thing as a “natural” death again. Only accidents or homicides.
Of course, since the human body has about 37 trillion cells, this process is easier said than done. That’s a hell of a lot of maintenance to put on technology that doesn’t even exist yet.
Nanobots are not alone as being the potential bringers of immortality. Genetic engineering also offers some hope in terms of changing how we age. If we can alter the way our DNA ages, we can extend our lives. CRISPR technology could allow us to edit our genes and work around diseases and degenerative conditions.
Another potential kind of immortality comes with abandoning the flesh. If you believe who you truly are exists in your mind, then what if you could upload your mind into a computer? Either into the cloud, or maybe even a robot designed to look like you.
If your mind could be transferred, fully and completely, that could be considered a kind of immortality. From your perspective, you would still be there. And, theoretically, this process could be done indefinitely even as your new artificial body falls apart after hundreds or thousands of years. As long as there’s still materials to make new bodies, what would stop you from continuing forever?
This idea sounds far-fetched, but scientists have already accomplished something similar. Not on such a grand scale as a human, but the mind of a roundworm was put into a Lego robot and a Lego robot started acting like a roundworm. That’s going to be the most terrifying sentence you hear all day, or the most amazing one. That happened all the way back in 2014, incidentally.
Can We Live Forever?
It’s an interesting question, to be sure. Could a human live forever? Or could we live 500 years? 1,000 years? The number of people who have suggested there are potential ways to extend our lives almost indefinitely seems encouraging, at least in terms of answering the question. But it’s also worth remembering that all of these different methods that might lead us to long life spans are speculative.
In much the same way someone can tell you about all the ways you could become a millionaire, the practical application is quite a bit different from the reality. They’re not even necessarily telling you something that’s untrue, it’s just knowing how something could happen and making it happen are often two very different things. In the end, we’ll know it works if it ever works. Until then, all we can do is keep speculating.