Lifespan is described by The Oxford English dictionary as “The length of time for which a person or animal lives or a thing functions.” Pragmatically, lifespan is defined as the period that the longest living member of a species has lived. Sometimes lifespan—or Maximum Lifespan—is used to refer to the longest period of time that a member of a species can live to. Scientists have not yet determined what the maximum length of time a human can live up to. This is an active theoretical field, and is home to lively speculation among some gerontologists. When it comes to humans, the oldest person that has ever lived defines lifespan. Verified by the Guinness World Records and the Gerontology Research Group, Jeanne Louise Calment, a French woman from Arles, lived to 122 years and 164 days. This lifespan remains the definition of human lifespan since her death in 1997.
In this regard, lifespan is an outlier—an extreme case of longevity. It is different from longevity, mean life span, average life span, life expectancy, individual lifespan, average age of death, average life expectancy and median age of death.
After the second World War, Max Klieber, a Swiss agricultural chemist, predicted that mass determines metabolism, and metabolism determines longevity. Larger animals tend to live longer. This theory has been elaborated in 2000 when a study that looked at nearly 4,100 longevity records of the highest documented age for a variety of fish, reptile, amphibian, bird, and mammalian species that included humans. There were four primary findings. First, longevity is positively correlated with body size between orders (e.g. the smaller rodents are shorter lived than the larger cetaceans) though not necessarily within orders—a biological grouping. As an example, longevity is not correlated with body size among seals and walruses. Second, animals that fly (i.e. birds and bats), or armored (turtles; armadillos) or live underground (moles; mole rats) tend to live longer than is predicted from body size alone. Third, there is great variance within species, so that lifespans vary by a factor of over 50 in mammals, herps and fish; and by over 15-fold in birds. Body size, metabolic rate, brain size all positively correlated with life span. Fourth, primates are long-lived mammals, the great apes (i.e. gorillas; chimpanzees) are long lived primates, and humans are extraordinarily long-lived great apes; human longevity exceeds nearly all other species both relatively and absolutely.
There is something uniquely human about great longevity, although it is not an exclusive characteristic of humans.
There are still some species that we have not yet observed a lifespan for. There are other species for whom we have not been able to observe mortality and therefore we do not have a lifespan for. There is a small jellyfish called turritopsis nutricula, that seems to regenerate itself from an adult back to an adolescent. A constant process of metamorphosis. These are also species that exhibit minimal aging. Kleiber’s Law was complicated by the work of Caleb Finch from the University of Southern California who—while researching aging among animals—found insignificant aging among rougheye rockfish (who can live up to 205 years), sturgeon (150 years for females), giant tortoise (152 years), bivalves and possibly lobsters. These included no observable age-related increases in mortality rate or decreases in reproduction rate after maturity, and no observable age-related decline in physiological capacity or disease resistance. Finch coined the term "negligible senescence" to describe very slow aging.
There have been three primary approaches to the study of lifespan; Genetic, Biological, and demographic using life expectancy and age of death. However, a new twist to lifespan studies emerged in a 2012 study by Kyung-Jin Min from the Inha University, and his Korean colleagues. These authors reported that during Chosun Dynasty between 14th to early 20th centuries Korean eunuchs lived 14 to 19 years longer than other (intact) men. Researchers were able to identify 81 eunuchs, who were castrated as boys, and determined that they lived to an average age of 70, significantly longer than other men of similar social status. Three of the eunuchs lived to 100. This is a centenarian rate that's far higher than would be expected today (one in 25,000.) Historically, but as recent as the 19th century, eunuchs were common across the world. Castrati boys—castrated beforepuberty—were among the most prized singers especially in catholic churches in Italy—the Sistine Chapel retained the last of the castrati singers—and Opera houses in Vienna. Elsewhere eunuchs were hired staff in harems and imperial palaces in Africa, China, Korea, Japan, and the rest of Asia and the Middle East. As well as in Europe and Russia.
In the 18th century there was a Christian sect called the Skoptzy, also known as the White Doves, whose male members—in order to attain their ideal of sanctity—subjected themselves to castration. They believed that the Messiah would not come until the Skoptsy numbered 144,000 (Rev. 14:1,4). Further East, in China, eunuchs played a more central role in government. Although in this context, castration was mostly apunishment, some subjected themselves to the procedure in order to gain employment. At the same time, during the Ottoman period, especially from the 16th century on, black eunuchs from Ethiopia or Sudan were in charge of the harem in the Ottoman court. Many of these boys were castrated at a monastery in Upper Egypt by Coptic priests. The practice was pervasive and endemic.
But the first time that eunuchs featured in longevity debates was with the observation by Serge Abrahamovitch Voronoff in the early 1900s. And it was not a positive observation. Voronoff—a French surgeon of Russian descent—worked at a hospital in Cairo from 1896 to 1910 where he had the opportunity to observe eunuchs. He noted their obesity, lack of body hair, and broad pelvises, as well as their flaccid muscles, lethargic movements, memory problems, and lowered intelligence. He concluded that the absence of testicles was responsible for aging and that their presence should prompt bone, muscle, nerve, and psychological development. He saw aging as the result of the lack of substance from the testicles and ovaries. This is all before we knew abouthormones. Voronoff gained fame for his technique of grafting monkey testicle tissue on to the scrotum of men to increase the lifespan. Voronoff and his predecessor and mentor Charles-Édouard Brown-Séquard—although ridiculed at the time—developed the field of endocrinology, the study of hormones. Voronoff observations was that castration had retarding effects. In 1999 Jean Wilson and Claus Roehrborn investigated the long-term effects of castration and concluded enlargement of the pituitary gland and decreased bone mineral density. There were also some reported growth of breasts in the Ottoman court eunuchs, which is also evident in photographs of Skoptzy men and Chinese eunuchs. Shrinkage of the prostate was common among eunuchs. However the authors could not resolve whether lifespan differed in their study. Such a study was done earlier in 1969, by James Hamilton and Gordon Mestler from the Department of Anatomy, State University of New York College of Medicine. In the turn of the 1900 it was common practice to castrate cognitively challenged children, a practice encouraged by the strong eugenics movement at that time. The study looked at mortality of patients in a mental institution with a population of 735 intact White males, 883 intact White females, and 297 White eunuchs. They reported that survival was significantly better in eunuchs than in intact males and females. This survival advantage started at age 25 years and continued throughout their life. The life expectancy for eunuchs was 69.3 years compared to 55.7 years in intact males. Males castrated at 8-14 years of age—before sexual maturation—were longer lived than males castrated at 20-39 years of age—after sexual maturation. Castration reduced the age of death by 0.28 years for every year of castration from age 39 and younger.
There are many changes that happen as a result of castration. The world was very different 600 years or even 100 years ago. In most cases it was a very violent world where men suffered early mortality through wars, famine, and petty violence. Eunuchs, because of their demeanor might have escaped that onslaught of violence. They might also have had more nurturing qualities that extended to looking after themselves better. We will never know.
What we observe in science tells us a very different story. Pragmatically we know that sex, and the activity surrounding sex, increases longevity. Howard Friedman in the Longevity Project longitudinal study provided our first glimpse into female orgasms and longevity. The study which was begun in 1921 by Lewis Terman of Stanford University, California looked at 1548 children with high intelligence born around 1910. Now in their nineties, the study morphed into a gerontological study. One of the interesting and pertinent findings was that women who had a higher frequency of orgasm tended to live longer than their less fulfilled sisters. No data on men was collected from this study. But a separate study in in the town of Caerphilly in south Wales, England, provided evidence for males as well. George Davey Smith from Department of Social Medicine, University of Bristol,, England, and his colleagues interviewed nearly 1,000 men about their sexual frequency, then followed up on their death records ten years later. The results determined that men who had two or more orgasms a week had died at a rate half that of the men who had orgasms less than once a month. And importantly there was a dose effect, where the more times these men had orgasms the longer they lived. These observations have been replicated in Sweden and in the USA for both male and female.
The most conclusive evidence on what promotes lifespan however comes from the masters of longevity themselves—centenarians. In the Blue Zones the cluster of centenarians teach us about the pragmatisms of living longer and sexual activity is a significant part of their life.
© USA Copyrighted 2015 Mario D. Garrett
In this regard, lifespan is an outlier—an extreme case of longevity. It is different from longevity, mean life span, average life span, life expectancy, individual lifespan, average age of death, average life expectancy and median age of death.
After the second World War, Max Klieber, a Swiss agricultural chemist, predicted that mass determines metabolism, and metabolism determines longevity. Larger animals tend to live longer. This theory has been elaborated in 2000 when a study that looked at nearly 4,100 longevity records of the highest documented age for a variety of fish, reptile, amphibian, bird, and mammalian species that included humans. There were four primary findings. First, longevity is positively correlated with body size between orders (e.g. the smaller rodents are shorter lived than the larger cetaceans) though not necessarily within orders—a biological grouping. As an example, longevity is not correlated with body size among seals and walruses. Second, animals that fly (i.e. birds and bats), or armored (turtles; armadillos) or live underground (moles; mole rats) tend to live longer than is predicted from body size alone. Third, there is great variance within species, so that lifespans vary by a factor of over 50 in mammals, herps and fish; and by over 15-fold in birds. Body size, metabolic rate, brain size all positively correlated with life span. Fourth, primates are long-lived mammals, the great apes (i.e. gorillas; chimpanzees) are long lived primates, and humans are extraordinarily long-lived great apes; human longevity exceeds nearly all other species both relatively and absolutely.
There is something uniquely human about great longevity, although it is not an exclusive characteristic of humans.
There are still some species that we have not yet observed a lifespan for. There are other species for whom we have not been able to observe mortality and therefore we do not have a lifespan for. There is a small jellyfish called turritopsis nutricula, that seems to regenerate itself from an adult back to an adolescent. A constant process of metamorphosis. These are also species that exhibit minimal aging. Kleiber’s Law was complicated by the work of Caleb Finch from the University of Southern California who—while researching aging among animals—found insignificant aging among rougheye rockfish (who can live up to 205 years), sturgeon (150 years for females), giant tortoise (152 years), bivalves and possibly lobsters. These included no observable age-related increases in mortality rate or decreases in reproduction rate after maturity, and no observable age-related decline in physiological capacity or disease resistance. Finch coined the term "negligible senescence" to describe very slow aging.
There have been three primary approaches to the study of lifespan; Genetic, Biological, and demographic using life expectancy and age of death. However, a new twist to lifespan studies emerged in a 2012 study by Kyung-Jin Min from the Inha University, and his Korean colleagues. These authors reported that during Chosun Dynasty between 14th to early 20th centuries Korean eunuchs lived 14 to 19 years longer than other (intact) men. Researchers were able to identify 81 eunuchs, who were castrated as boys, and determined that they lived to an average age of 70, significantly longer than other men of similar social status. Three of the eunuchs lived to 100. This is a centenarian rate that's far higher than would be expected today (one in 25,000.) Historically, but as recent as the 19th century, eunuchs were common across the world. Castrati boys—castrated beforepuberty—were among the most prized singers especially in catholic churches in Italy—the Sistine Chapel retained the last of the castrati singers—and Opera houses in Vienna. Elsewhere eunuchs were hired staff in harems and imperial palaces in Africa, China, Korea, Japan, and the rest of Asia and the Middle East. As well as in Europe and Russia.
In the 18th century there was a Christian sect called the Skoptzy, also known as the White Doves, whose male members—in order to attain their ideal of sanctity—subjected themselves to castration. They believed that the Messiah would not come until the Skoptsy numbered 144,000 (Rev. 14:1,4). Further East, in China, eunuchs played a more central role in government. Although in this context, castration was mostly apunishment, some subjected themselves to the procedure in order to gain employment. At the same time, during the Ottoman period, especially from the 16th century on, black eunuchs from Ethiopia or Sudan were in charge of the harem in the Ottoman court. Many of these boys were castrated at a monastery in Upper Egypt by Coptic priests. The practice was pervasive and endemic.
But the first time that eunuchs featured in longevity debates was with the observation by Serge Abrahamovitch Voronoff in the early 1900s. And it was not a positive observation. Voronoff—a French surgeon of Russian descent—worked at a hospital in Cairo from 1896 to 1910 where he had the opportunity to observe eunuchs. He noted their obesity, lack of body hair, and broad pelvises, as well as their flaccid muscles, lethargic movements, memory problems, and lowered intelligence. He concluded that the absence of testicles was responsible for aging and that their presence should prompt bone, muscle, nerve, and psychological development. He saw aging as the result of the lack of substance from the testicles and ovaries. This is all before we knew abouthormones. Voronoff gained fame for his technique of grafting monkey testicle tissue on to the scrotum of men to increase the lifespan. Voronoff and his predecessor and mentor Charles-Édouard Brown-Séquard—although ridiculed at the time—developed the field of endocrinology, the study of hormones. Voronoff observations was that castration had retarding effects. In 1999 Jean Wilson and Claus Roehrborn investigated the long-term effects of castration and concluded enlargement of the pituitary gland and decreased bone mineral density. There were also some reported growth of breasts in the Ottoman court eunuchs, which is also evident in photographs of Skoptzy men and Chinese eunuchs. Shrinkage of the prostate was common among eunuchs. However the authors could not resolve whether lifespan differed in their study. Such a study was done earlier in 1969, by James Hamilton and Gordon Mestler from the Department of Anatomy, State University of New York College of Medicine. In the turn of the 1900 it was common practice to castrate cognitively challenged children, a practice encouraged by the strong eugenics movement at that time. The study looked at mortality of patients in a mental institution with a population of 735 intact White males, 883 intact White females, and 297 White eunuchs. They reported that survival was significantly better in eunuchs than in intact males and females. This survival advantage started at age 25 years and continued throughout their life. The life expectancy for eunuchs was 69.3 years compared to 55.7 years in intact males. Males castrated at 8-14 years of age—before sexual maturation—were longer lived than males castrated at 20-39 years of age—after sexual maturation. Castration reduced the age of death by 0.28 years for every year of castration from age 39 and younger.
There are many changes that happen as a result of castration. The world was very different 600 years or even 100 years ago. In most cases it was a very violent world where men suffered early mortality through wars, famine, and petty violence. Eunuchs, because of their demeanor might have escaped that onslaught of violence. They might also have had more nurturing qualities that extended to looking after themselves better. We will never know.
What we observe in science tells us a very different story. Pragmatically we know that sex, and the activity surrounding sex, increases longevity. Howard Friedman in the Longevity Project longitudinal study provided our first glimpse into female orgasms and longevity. The study which was begun in 1921 by Lewis Terman of Stanford University, California looked at 1548 children with high intelligence born around 1910. Now in their nineties, the study morphed into a gerontological study. One of the interesting and pertinent findings was that women who had a higher frequency of orgasm tended to live longer than their less fulfilled sisters. No data on men was collected from this study. But a separate study in in the town of Caerphilly in south Wales, England, provided evidence for males as well. George Davey Smith from Department of Social Medicine, University of Bristol,, England, and his colleagues interviewed nearly 1,000 men about their sexual frequency, then followed up on their death records ten years later. The results determined that men who had two or more orgasms a week had died at a rate half that of the men who had orgasms less than once a month. And importantly there was a dose effect, where the more times these men had orgasms the longer they lived. These observations have been replicated in Sweden and in the USA for both male and female.
The most conclusive evidence on what promotes lifespan however comes from the masters of longevity themselves—centenarians. In the Blue Zones the cluster of centenarians teach us about the pragmatisms of living longer and sexual activity is a significant part of their life.
© USA Copyrighted 2015 Mario D. Garrett
Further Readings
Buettner, Dan. "The island where people forget to die." The New York Times. (2012).
Carey, J., and D. Judge. "Longevity records: life spans of mammals, birds, amphibians, reptiles, and fish." On-line). Accessed September 14. (2002).
Cuperschmid, Ethel Mizrahy, and Tarcisio Passos Ribeiro de Campos. "Dr. Voronoff's curious glandular xeno-implants." História, Ciências, Saúde-Manguinhos 14, no. 3: 737-760. (2007).
Finch, Caleb E. "Variations in senescence and longevity include the possibility of negligible senescence." The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 53.4: B235-B239. (1998).
Finch, Caleb E., and Malcolm C. Pike. "Maximum life span predictions from the Gompertz mortality model." The Journals of Gerontology Series A: Biological Sciences and Medical Sciences 51.3: B183-B194. (1996).
Friedman, Howard. The Longevity Project: Surprising Discoveries for Health and Long Life from the Landmark Eight Decade Study. Hay House, Inc, (2011).
Hamilton, James B., and Gordon E. Mestler. "Mortality and survival: comparison of eunuchs with intact men and women in a mentally retarded population." Journal of Gerontology 24, no. 4 : 395-411. (1969).
Kleiber, Max. "Body size and metabolic rate." Physiol. Rev 27.4 (1947): 511-541.
Kyung-Jin Min, Lee, Cheol-Koo and Park Han-Nam. "The lifespan of Korean eunuchs." Current Biology 22, no. 18: R792-R793. (2012).
McWhirter N, McWhirter R, editors. The Guinness Book of Records. London, UK: Random House Publishing Group. (1986).
Piraino, Stefano, et al. "Reversing the life cycle: medusae transforming into polyps and cell transdifferentiation in Turritopsis nutricula (Cnidaria, Hydrozoa)." Biological Bulletin. 302-312. (1996).
Smith, George Davey, Stephen Frankel, and John Yarnell. "Sex and death: are they related? Findings from the Caerphilly cohort study." British Medical Journal 315, no. 7123 : 1641-1644. (1997).
Vaupel, James W, Baudisch, Annette, Dolling, Martin, Roach, Deborah A, Gampe, Jutta. “The case for negative senescence.” Theoretical population biology. 65(4) 339-51. (2004).
Vaupel, James W. Biodemography of human ageing. Nature 464. 7288: 536-42. (2010).
Wilson, Jean D., and Claus Roehrborn. "Long-term consequences of castration in men: lessons from the Skoptzy and the eunuchs of the Chinese and Ottoman courts." The Journal of Clinical Endocrinology & Metabolism 84, no. 12: 4324-4331.(1999).
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