Authored by Gavin Zhou, Biological Sciences ‘25
Art by Ishani Chopra, Biological Sciences and Biometry & Statistics '24
On August 4, 1997, Jeanne Calment died in the Mediterranean town of Arles, France, at the young age of 122 years old [1]. Since then, no one has surpassed her. In fact, no one has come close. With Kane Tanaka passing away at 119 in April of 2022, Calment remains the only person to live beyond 120 years of age [2].
Such supercentenarians are quite intriguing. They often defy what modern medical knowledge would suggest. Calment, for instance, smoked for all of her life [1]. The supercentenarian population is heterogeneous with differing habits, diets, personalities, and so-called secrets to longevity [1]. However, it is certain that modern medicine played an important role in helping the oldest humans reach their old age. Calment required hip surgery at age 115, while others survived stroke or heart failure [1]. Lucile Randon, who passed away in January 2023 at the age of 118, survived after a battle with COVID-19 [3].
Despite medicine and technology continuing to improve, the upper bound on age currently appears stagnant. While life expectancy rates continue to rise each year, this trend is mostly attributed to the decrease in childhood mortality [4]. Meanwhile, maximum lifespan has been shown to be rather fixed in a species [4].
Obtaining an extremely long lifespan is not the focus of selection and evolution. There is no apparent evolutionary advantage for being able to reach old age [5]. Conversely, lifespan is often inversely related to reproductive success earlier in life [6]. Evolution only selects for individuals who can survive long enough to reproduce, so when given the choice between reproduction and lifespan, natural forces generally choose reproduction [6]. Thus, any attempt to lengthen maximum human lifespan would have little help from the eons of natural processes.
With the plateau of humans' oldest age, many researchers have theorized that we are approaching the limit for human lifespan [4]. Some use the previously mentioned evolutionary argument to reason for this limit [4][5]. Others have used statistical methods, combined with data on markers in human blood to argue that human lifespan is capped at age 120-150 [7]. At that point, humans lose all physiological resilience, so this age represents the physical limit of the human body. It appears that even if we wanted to, we could not live past this age.
Research into human physiology has suggested a limit as the reason that Calment’s record still stands, but other experts have looked into alternative explanations. Some studies have indicated that extremely old people tend not to receive as high quality medical care [8]. The researchers mentioned several causative reasons. First, there is the societal belief that younger people should be prioritized for medical care. Similarly, many believe that it is more important to die peacefully than to undergo intensive and invasive medical treatment. Lastly, elderly individuals may be more likely to refuse medical care [8]. When Calment passed away, she had no close relatives and appeared to be perfectly comfortable with death [1]. Aging researchers who argue against a human lifespan limit believe that, just as modern medicine has artificially allowed many supercentenarians to live to their age, caring for the health of such extremely old people could continue the lengthening of life [8]. Many supercentenarians are said to be of relatively good health when they die, and their death is often said to be caused by old age, with no specific causes. Yet, in many of these cases there are, in fact, specific diseases that explain their passing [8]. If these can be identified and properly treated, the maximum human lifespan may not have a limit.
Since Calment’s death in 1997, the world has not seen anyone to surpass 120 years of age. This plateau led to many theorizing that we may have reached our lifespan limit, citing evolutionary and physiological data. Yet, others argue that the stagnation comes more from personal and societal attitudes toward old people, and that the lengthening of lifespan could be achieved with a shift in our view of medical treatment for old people. Even if human physiology has set a limit, many innovations in medicine would have been thought to be physically impossible previously. Then, if it is established that we can, the debate becomes whether we should.
Works Cited
Maier, H., Gampe, J., Jeune, B., Vaupel, J. W., & Robine, J. M. (Eds.). (2010). Supercentenarians. Springer Science & Business Media.
BBC News. (2022, April 25). Kane Tanaka: Japanese woman certified world's oldest person dies. https://www.bbc.com/news/world-asia-61218239
Porterfield, C. (2023, January 17). World’s oldest known person dies at age 118. Forbes. https://www.forbes.com/sites/carlieporterfield/2023/01/17/worlds-oldest-known-person-dies-at-age-118/?sh=6533fb4c72c7
Dong, X., Milholland, B. & Vijg, J. Evidence for a limit to human lifespan. Nature 538, 257–259 (2016). https://doi.org/10.1038/nature19793
Milholland, B., Vijg, J. Why Gilgamesh failed: the mechanistic basis of the limits to human lifespan. Nat Aging 2, 878–884 (2022). https://doi.org/10.1038/s43587-022-00291-z
Austad, S., Hoffman, J. Is antagonistic pleiotropy ubiquitous in aging biology? Evolution, Medicine, and Public Health 1, 287–294 (2018). https://doi.org/10.1093/emph/eoy033
Pyrkov, T.V., Avchaciov, K., Tarkhov, A.E. et al. Longitudinal analysis of blood markers reveals progressive loss of resilience and predicts human lifespan limit. Nat Commun 12, 2765 (2021). https://doi.org/10.1038/s41467-021-23014-1
Blagosklonny M. V. (2021). No limit to maximal lifespan in humans: how to beat a 122-year-old record. Oncoscience, 8, 110–119. https://doi.org/10.18632/oncoscience.547
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