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:''(Life Extension (LE) is also a [[fictional company]] appearing in the motion picture [[Abre los ojos]] (1997) and its remake [[Vanilla Sky]] (2001).)''
:''(Life Extension (LE) is also a [[fictional company]] appearing in the motion picture [[Abre los ojos]] (1997) and its remake [[Vanilla Sky]] (2001).)''


'''Life extension''' in an increase in the maximum [[life expectancy|lifespan]] beyond the current maximum lifespan, especially for humans. For those who regard [[aging]] as a [[disease]], [[Wiktionary:therapy|therapeutic]] methods to achieve maximum lifespan are anti-[[aging]] [[medicine]]. Whether human lifespan can or should be extended is the subject of much controversy.
'''Life extension''' consist of attempts to extend human life beyond the current maximum lifespan.


==Strategies for life extension==
==History of Life Extension==


In 1970, the American Aging Association was formed under the impetus of Denham Harman, MD, PhD, originator of the [[free radical theory]] of [[aging]]. Dr. Harmon wanted an organization of [[gerontology|biogerontologists]] that was devoted to research and to the sharing of information
Several strategies are promoted:
among scientists interested in extending human lifespan.


Although humans have been seeking to extend their lives from the time of the ancient [[Sumer|Sumerian]] king [[Gilgamesh]], the 1982 bestselling book ''Life Extension'' by Durk Pearson and Sandy Shaw popularized the phrase. The book deals largely with [[antioxidant]]
** [[Calorie restriction]] (CR) has consistently extended the maximum life-spans of laboratory animals. Indeed, it is the only anti-aging regimen currently available (aside from those with a few, not yet repeated studies backing them) that consistently works in higher organisms. It works on every animal in which tests have been completed, from rotifers up to guinea pigs, and preliminary results on [[Rhesus monkey]]s are promising. It was first popularized by Dr. [[Roy Walford]]. Unfortunately, most humans would probably find an extreme version of CR difficult, but no studies of adaptability to the diet have been completed. Also, the program must be started in young [[adulthood]] for maximum benefit, however, there is considerable evidence that CR will have significant benefits when started in adulthood, provided it isn't initiated all at once, which may even be risky. The [http://www.calorierestriction.org CR Society] is an advocacy group for people interested in implementing CR, and actively seeks to find ways to make CR "liveable." Calorie restriction can be implemented either as reduced regular feeding, or as days of [[fasting]] alternating with days of free-feeding. Calorie restriction works, according to one theory, because blood [[glucose]] levels remain lower than when [[food energy]] is unrestricted. But much new research is underway exploring genetic changes that take place during CR. Many researches now think that a perspective based on a theory of [[hormesis]] probably best explains the effects of CR.
[[Dietary supplement|supplements]], and is dedicated foremost to Dr. Denham Harman. The 1980 book ''The Life Extension Revolution'' by Saul Kent did not sell so well. But Mr. Kent appeared on the ''Merv Griffith Show'' with Pearson and Shaw, and was able to use the flood of letters to create a mail order company for [[nutraceutical]]s called the Life Extension
**Research on drugs to mimic calorie restriction continues. A number of possible [[CR-mimetics]] are under study. The most available may be [[Resveratrol]], which is available over the counter as a supplement. In [[2003]], the [http://www.lef.org Life Extension Foundation] funded [[DNA microarray|gene-chip]] research comparing [[gene expression]] in calorically-restricted mice with the gene expressions of mice on various prescription drugs, including especially diabetic drugs. The researchers found that the diabetic drug [[Metformin]] (trade-marked Glucophage) had identical gene expression in mice, within the limits of measurement. It is also said to have extended the life span of mice.
Foundation.
** [[Stem cell therapy]] would be used to replace damaged or diseased cells in living tissue.


Money generated from the Life Extension Foundation allowed Saul Kent to finance the [[Alcor Life Extension Foundation]], the largest [[cryonics]] organization. [[Alcor Life Extension Foundation|Alcor]] gained national prominence when the baseball star [[Ted Williams]] was cryonically preserved by Alcor in 2002 and a family dispute arose as to whether Ted had
* [[Gene therapy]] to repair damaged or diseased cells (including [[cancer]]). This would include extension of teleomeres to reduce cellular aging and induced failures of telomerase to prevent growth of cancers. [[Aubrey de Grey]]'s "[[engineered negligible senescence]]" proposes to substantially extend human lifespan with a short series of particular cellular therapies.
really wanted to be [[cryopreservation|cryopreserved]].
** Breaker medication to remove glycosylated (sugar-damaged) [[protein]]s and to restore elasticity to the organs, especially the heart. The most famous is [[Acetyl-L-carnitine]], an amino salt available in [[health-food store]]s in the U.S. There is, however, no clinical evidence that Acetyl-L-carnitine affects aging.
** Supplementation of [[chromium]] to increase insulin efficiencies and reduce blood sugar loads. There is as of yet no clinical evidence that chromium affects aging in humans, but some studies in lab animals are suggestive.
** [[Antioxidants]] to reduce oxidative damage to the body. This does not extend maximum life span, but does increase average life-spans in a population of mice, indicating that it might does reduce metabolic damage. Popular ones include vitamins E, and C. Certain natural antioxidant enzymes, superoxide dismutase is the most common, require adjuvant minerals on their active sites. The most common form of superoxide dismutase requires an atom of [[selenium]]. Another common dismutase requires an atom of [[copper]], another [[zinc]].
**Mild [[exercise]] can provide some protection against system failures, and has other small effects. In particular, exercised elderly people are generally less frail, and less prone to break bones, or have other catastrophic incidents. Mild strength, [[aerobic]] and flexibility training were all helpful against fragility, with strength training having the largest effect per unit of time spent by subjects. In mice, mild exercise (on wheels) lengthens average lifespan, and has a nearly unmeasurable (<2%) lengthening effect on maximum life spans. Heavy exercise shortens mices' maximum lifespans by 5%, but lengthens average life spans. These small effects might be explained by recent research that shows that stem cells are attracted by the cytokines released from mild damage, exactly the sort of damage that might be produced by mild exercise.
** A widely-known therapy against lipofuscin (waste build-up in the cell) is large doses of an enzymic cofactor called [[ubiquinone]], or CoQ10. CoQ10 forms chains attached to proteins. A chain of three CoQ10 molecules marks a protein as "old" and allows cellular digestive enzymes to attach to it and cleave it. Heavy chronic doses of CoQ10 can gradually reduce senile confusion, lower blood pressure, and cause age-spots to fade. CoQ10 is available as a supplement in most U.S. health food stores. However, studies of CoQ10 in animals have shown no effect on life span, and it may even be harmful.
** [[Hormone therapy|Hormone therapies]] partially reverse some of the effects of aging. Growth hormone supplementation reverses many of the hormonal effects of aging, including sexual hormones, and losses of muscle and immune function. In mice, it reduces maximum life-span slightly, while slightly increasing average life-span. Hormone therapies with sex hormones (i.e. [[estrogen]], [[progesterone]] or [[testosterone]]) or their precursors ([[DHEA]]) are more controversial. Although sexual functions increase, side effects to other body systems are substantial.
** Some people interested in life extension are interested in [[cryonics]], as an alternative to certain death from age-related damage. The cost ranges from thirty thousand ([[Cryonics Institute]]) to a hundred and twenty thousand dollars ([[Alcor Life Extension Foundation]]). It is usually funded by life insurance.
** The advent of [[medical nanorobotics]] in the next few decades could allow significant increases in the human healthspan [http://www.rfreitas.com/Nano/DeathIsAnOutrage.htm].


In 1983, Dr. [[Roy Walford]], a life-extensionist [[gerontology|gerontologist]] published a popular book called ''Maximum Lifespan''. Later, Dr.&nbsp;Walford and his student Dr.&nbsp;Richard Weindruch, summarized years of their research into the ability of [[calorie restriction]] to extend the lifespan of [[rat]]s in their 1988 scholarly work ''The Retardation of Aging and Dietary Restriction''. It had been known since the work of Clive McCay in the
==Related articles==
1930s that calorie restriction can extend the maximum lifespan of rodents. But it was the work of Walford and Weindrich that gave detailed scientific grounding to that knowledge. Walford's personal interest in life extension motivated his scientific work and he practiced calorie restriction himself.
* [[Afterlife]]

* [[Biogerontology]]
In 1993 the American Academy of Anti-Aging Medicine (A4M) was formed to create an anti-aging medical specialty distinct from [[geriatrics]], and to hold conferences for physicians interested in this field.

The most recent development in life extension has been the work of [[gerontology|biogerontologist]] [[Aubrey de Grey]] of [[Cambridge University]]. Dr.&nbsp;de Grey proposes that damage to [[macromolecule]]s, [[cell (biology)|cell]]s, [[biological tissue|tissue]]s and [[organ (anatomy)|organ]]s can be repaired by advanced [[biotechnology]].

==Strategies of Life Extension==

===Anti-Aging Medicine===

Much of anti-aging medicine has been concerned with the use of nutritional supplements to extend lifespan. Because of the [[free radical theory]] of [[aging]] it has been believed that [[antioxidant]] [[Dietary supplement|supplements]] like [[tocopherol|Vitamin&nbsp;E]], [[lipoic acid]] and [[acetylcysteine|N-acetylcysteine]] might extend human life. Because [[diabetes]] resembles [[aging]] and is associated with cross-linking of [[protein]]s seen with aging, it has been believed that anti-[[glycation|glycating]] supplements like [[carnosine]]
and [[lysine]] might reduce aging. Because natural hormones decline with age, it has been believed that restoring [[growth hormone]], [[melatonin]] or [[dehydroepiandrosterone|dhea]] to youthful levels might be a means of restoring youth.

===Calorie Restriction===

[[Calorie restriction]] (CR) with adequate nutrition has been shown to extend the lifespans of almost every species on which it has been tested, including not only rats, but yeast, fruit flies and nematodes. Experiments are in progress with primates to show that calorie restriction can extend the lifespan of long-lived species. A mutual support group called the Calorie Restriction Society was formed with the help of [[Roy Walford]] in the mid-1990s. These people
have the willpower and determination to restrict their caloric intake in the hope of extending their lives, but they are very few in number. They communicate by e-mail and have been flown to [[Washington University]] in St.&nbsp;Louis to be studied by Dr.&nbsp;John Holloszy.

===SENS (Strategies for Engineered Negligible Senescence)===

Dr.&nbsp;[[Aubrey de Grey]] believes that it will someday be possible for humans to live thousands of years in a youthful condition. He calls his project to reverse the damage we call '''''aging''''' '''[[Engineered negligible senescence|SENS]]''' ('''[[Engineered negligible senescence|Strategies for Engineered Negligible Senescence]]'''). He has seven
strategies for the &quot;seven deadly sins&quot;:

# Cell loss can be repaired (reversed) just by suitable exercise in the case of muscle, but for other tissues it needs various growth factors to stimulate cell division, or in some cases it needs stem cells.
# Senescent cells can be removed by activating the immune system against them. Or they can be destroyed by gene therapy to introduce &quot;suicide genes&quot; that only kill senescent cells.
# Protein cross-linking can largely be reversed by drugs that break the links. But for some of the links we may need to develop enzymatic methods.
# Extracellular garbage can be eliminated by vaccination that gets immune cells to &quot;eat&quot; the garbage.
# For intracellular junk we need to introduce new enzymes, possibly enzymes from soil bacteria, that can degrade the junk that our own natural enzymes cannot degrade.
# For mitochondrial mutations the plan is not to repair them but to prevent harm from the mutations by putting suitably modified copies of the mitochondrial genes into the nucleus by gene therapy. The mitochondrial DNA experiences so much mutation damage because most free radicals are generated in the mitochondria. If mitochondrial DNA can be moved into the nucleus it will be better protected from free radicals, and there will be better DNA repair when damage occurs. All mitochondrial proteins would then be imported into the mitochondria.
# For cancer (the most lethal consequence of mutations) the strategy is to use gene therapy to delete the genes for telomerase and to eliminate telomerase-independent mechanisms of turning normal cells into &quot;immortal&quot; cancer cells. To compensate for the loss of telomerase in stem cells we would introduce new stem cells every decade or so.

Dr. de Grey has created a [[Methuselah Mouse Prize]] which awards money to researchers who can extend the lifespan of [[mouse|mice]] or [[rejuvenation (aging)|rejuvenate]] mice.

===Cryonics===

[[Cryonics]] is inspired by the fact that life extension technologies may eventually allow people to live thousands of years of youthful life. But these technologies may not be available to for another 50 years. There is a danger that anyone, including young people, may die before the new medicine becomes available. Cryopreservation shortly after legal death may provide an
&quot;ambulence&quot; into the future. The assumption of cryonics is that at [[cryogenic]] temperatures there will be no alteration in biological tissue for thousands of years, which allows plenty of time for future medicine to achieve the required capabilities.

For those in cryonics, future medicine will not only be able to cure all disease and rejuvenate everyone to a youthful condition, but it will be able to repair any damage that is caused by the cryopreservation process. Molecular repair technology ([[nanotechnology]] and [[nanomedicine]]) is expected to be able to achieve these results. But to be safe, and to
minimize damage, efforts are being made to eliminate all freezing damage through [[vitrification]] and to minimize [[ischemia|ischemic]] damage through rapid cooling and [[cardio]]-[[lung|pulmonary]] support immediately following pronouncement of death.

==Scientific Controversy about Life Extension==

===Anti-Aging Medicine===

Although [[Alex Comfort]] was an anti-aging [[gerontology|gerontologist]] ahead of his time, other &quot;old guard&quot; [[gerontology|biogerontologists]] vehemently deny that aging is a disease. Possibly the most prominent biogerontologist making this denial is [[Leonard Hayflick]], who determined that fibroblasts are limited to around 50&nbsp;cell divisions. Hayflick reasons that aging is an unavoidable consequence of [[entropy]].

Dr. Denham Harman spent years experimenting with [[antioxidant]]s, and was only able to establish that they can extend mean lifespan, but was not able to demonstrate an effect on maximum lifespan. In response to what they saw as unscrupulous profiteering by those
engaged in the selling of [[Dietary supplement|supplements]] and the practice of anti-aging medicine, a group of prominent [[gerontology|biogerontologists]] began a &quot;war&quot; on
anti-aging medicine in general and the A4M in particular. Jay Olshansky,[[Leonard Hayflick]], and Bruce Carnes wrote an position paper against anti-aging medicine that was published
in ''Science'' magazine.

===Calorie Restriction===

Despite the results on [[yeast]], [[Drosophila melanogaster|fruit flies]] and [[Caenorhabditis elegans|nematodes]], criticisms have been raised that the results of calorie restriction experiments on laboratory rats are invalid because years of inbreeding have made these animals different from those found in the wild. Even when it is conceded that the rat work may be valid, some argue that the results are only applicable to short-lived species because such species have evolved to respond to feast and famine with alterations in longevity. Proving that the results are valid is difficult, because experiments with long-lived species necessarily take a very long time to perform.

Despite thousands of scientific papers demonstrating the efficacy of calorie restriction on a wide range of animals, the subject is virtually never mentioned in nutrition textbooks.

===SENS (Strategies for Engineered Negligible Senescence)===

The SENS project is criticized as a pipedream based on pure speculation, rather than any proven science. [[Aubrey de Grey]] has been criticized on the grounds that he is a theoretician who does no empirical work himself. Yet Dr.&nbsp;de Grey has a phenomenal capacity to organize working scientists, to conduct scientific conferences, and to be editor-in-chief of the peer-reviewed journal ''Rejuvenation Research''.

===Cryonics===

[[Cryonics]] is not current science, it is based on anticipations of the capabilities of future science. No mammal has been cryopreserved and brought back to life. Nonetheless, [[vitrification]] has made remarkable strides in eliminating freezing damage and maintaining viability of cryopreserved tissues. One is reminded of all the scientists who said cloning would be impossible not so long ago. Routinely journalists interview scientists who know
nothing about cryonics and are told that it can never work because of freezing damage (being totally unaware that cryonics organizations use [[cryoprotectant]]s). As often as not they
display their ignorance by referring to [[cryonics]] as &quot;[[cryogenics]]&quot;. The most often quoted phrase is that &quot;believing cryonics could reanimate somebody who has been frozen is like believing you can turn hamburger back into a cow.&quot;

==Ethics and Politics of Life Extension==

===Anti-Aging Medicine===

Life extensionists commonly hear the accusation that they would destroy the planet with overpopulation. The conservative so-called [[ethicist]] Leon Kass has exemplified the anti-life
extension view with this statement that:

:&quot;simply to covet a prolonged life span for ourselves is both a sign and a cause of our failure to open ourselves to procreation and to any higher purpose. … [The] desire to prolong youthfulness is not only a childish desire to eat one’s life and keep it; it is also an expression of a childish and narcissistic wish incompatible with devotion to posterity.&quot;

To a life extensionist the words of the anti-life extensionist as nothing less than the death-threats of fascists who have no conception of &quot;live and let live&quot; or of individual
choices. Kass would use government power to ensure that no one's life is extended, whatever they may wish:

:&quot;the finitude of human life is a blessing for every individual, whether he knows it or not.&quot;

For years the [[Food and Drug Administration|FDA]] tried to destroy the Life Extension Foundation, through attacks by armed government agents, through seizure of merchandise and through court action. The FDA refused to regard aging as a disease or life extension as a valid treatment category. In 1991 Saul Kent and Bill Faloon, the principals of the foundation were thrown in jail and told by the FDA that would become the target of criminal indictments that would &quot;destroy their lives forever&quot; and were told to plead guilty of crimes against the state. Against the advice of all their lawyers, Kent and Faloon fought the FDA in court and filed countercharges concerning their mistreatment. In 1995 the FDA told Kent and Faloon that in exchange for a guilty plea they would not have to go to prison and could continue doing business on a more limited basis. Instead of pleading guilty, Kent and Faloon filed a new battery of legal motions, escalated their counterattack against the FDA and began extensive preparations for their trial. In November 1995, the FDA dropped all charges except the charge of &quot;obstruction of justice&quot; against Saul Kent. In February, 1996 even this charge was dropped.

===SENS (Strategies for Engineered Negligible Senescence)===

''Technology Review'', which is owned by the [[Massachusetts Institute of Technology]], published an article in February 2005 that painted an unfavorable portrait of [[Aubrey de Grey]], the man, supplemented with an attack on his science. The interviewer concluded that
Dr.&nbsp;de Grey &quot;would surely destroy us in attempting to preserve us&quot; because living for such long periods would undermine what it means to be human. In an effort to
destroy SENS, Jason Pontin (the magazine's editor) offered $10,000 to any gerontologist who could prove to an independent review panel that de Grey's ideas about radical life-extension
had no merit. Dr.&nbsp;de Grey retaliated by matching the $10,000 and making the prize for debunking him a generous $20,000. So far there have been no takers.

===Cryonics===

As a life extension practice, [[cryonics]] has been under attack for many of the same reasons as the other life extension practices. Additionally, however, people are aesthetically revolted by the practice of [[cryopreservation|cryopreserving]] &quot;dead bodies&quot; and especially of cryopreserving heads (&quot;neuropreservation&quot;).

Almost from the beginning the Society for [[Cryobiology]] has attacked cryonics as being &quot;fraud&quot; and &quot;quackery&quot; and has banned cryonicists from being members of the Society. There are cryonicists who are members, but they are necessarily discreet about their affiliations. Most of the members of the Society have also made it clear that they have non-scientific grounds for their hostility, including the usual anti-life extension arguments as well as aesthetic arguments. Additionally, like many scientists, many of the Society members are simply conformists, who try to espouse beliefs that they believe are acceptable to their peers.

As a result of the [[Ted Williams]] media circus surrounding cryonics, a bill was passed in 2004 by the Arizona House of Representatives to place cryonics and cryonics procedures under
the regulation of the state funeral board. In its original form the law would have prevented [[Alcor Life Extension Foundation|Alcor]]'s use of the UAGA. The bill was withdrawn.
Although it was not responsible for Ted Williams, the media circus resulted in the [[Cryonics Institute]] (CI) being placed under a "Cease and Desist" order by the State of [[Michigan]] for six months. Finally the Michigan government decided to regulate CI as a [[cemetery]].

There are many people who hate cryonics and who hate cryonicists. The [[Ted Williams]] affair has become a focus of such people. A novel was recently written that portrayed a baseball star cryopreserved by a cryonics organization. The novel had the &quot;happy ending&quot; of a determined suicidal cryonics-hater flying an airplane into a cryonics
facility -- destroying himself and everyone within the building.

==See Also==

* [[Gerontology|Biogerontology]]
* [[Biological immortality]]
* [[Biological immortality]]
* [[Cryonics]]
* [[Cryonics]]
* [[Immortality]]
* [[Immortality]]
* [[Longevity]]
* [[Longevity]]
* [[Senescence]]
* [[The Methuselah Mouse Prize]]
* [[The Methuselah Mouse Prize]]


==External links==
==External Links==
* [http://www.gen.cam.ac.uk/sens/ Strategies for Engineered Negligible Senescence (SENS)]
* [http://www.benbest.com/lifeext/aging.html Mechanisms of Aging]
* [http://www.lef.org/ Life Extension Foundation]
* [http://www.senescence.info senescence.info]
* [http://www.alcor.org/ The Alcor Life Extension Foundation]
* [http://www.alcor.org/ The Alcor Life Extension Foundation]
* [http://www.cryonics.org/ The Cryonics Institute]
* [http://www.cryonics.org/ The Cryonics Institute]
* [http://www.calorierestriction.org/ The Calorie Restriction Society]
* [http://www.calorierestriction.org/ The Calorie Restriction Society]
* [http://www.lef.org/ Life Extension Foundation]
* [http://www.medspa.squarespace.com/anti-aging-medicine/ Articles On Aging]
* [http://www.benbest.com/lifeext/whylife.html Why Life Extension or Why Live at All?]
* [http://www.senescence.info senescence.info]
* [http://www.gen.cam.ac.uk/sens/ Strategies for Engineered Negligible Senescence (SENS)]
* [http://www.worldhealth.net/ American Academy of Anti-Aging Medicine (A4M)]
*[http://www.benbest.com/lifeext/aging.html Mechanisms of Aging]
* [http://anti-ageing.us/blogger.html Anti-Aging Medicine & Science Blog]
* [http://www.xenophilia.org/nano_life_extension.html Nanotechnology and Life Extension]
*[http://www.medspa.squarespace.com/anti-aging-medicine/ Articles On Aging]
*[http://www.benbest.com/lifeext/whylife.html Why Life Extension or Why Live at All?]
*[http://www.worldhealth.net/ American Academy of Anti-Aging Medicine (A4M)]
*[http://anti-ageing.us/blogger.html Anti-Aging Medicine & Science Blog]
*[http://www.xenophilia.org/nano_life_extension.html Nanotechnology and Life Extension]



[[category:Protoscience]]
[[category:Transhumanism]]
[[category:Transhumanism]]

Revision as of 03:18, 30 October 2005

(Life Extension (LE) is also a fictional company appearing in the motion picture Abre los ojos (1997) and its remake Vanilla Sky (2001).)

Life extension in an increase in the maximum lifespan beyond the current maximum lifespan, especially for humans. For those who regard aging as a disease, therapeutic methods to achieve maximum lifespan are anti-aging medicine. Whether human lifespan can or should be extended is the subject of much controversy.

History of Life Extension

In 1970, the American Aging Association was formed under the impetus of Denham Harman, MD, PhD, originator of the free radical theory of aging. Dr. Harmon wanted an organization of biogerontologists that was devoted to research and to the sharing of information among scientists interested in extending human lifespan.

Although humans have been seeking to extend their lives from the time of the ancient Sumerian king Gilgamesh, the 1982 bestselling book Life Extension by Durk Pearson and Sandy Shaw popularized the phrase. The book deals largely with antioxidant supplements, and is dedicated foremost to Dr. Denham Harman. The 1980 book The Life Extension Revolution by Saul Kent did not sell so well. But Mr. Kent appeared on the Merv Griffith Show with Pearson and Shaw, and was able to use the flood of letters to create a mail order company for nutraceuticals called the Life Extension Foundation.

Money generated from the Life Extension Foundation allowed Saul Kent to finance the Alcor Life Extension Foundation, the largest cryonics organization. Alcor gained national prominence when the baseball star Ted Williams was cryonically preserved by Alcor in 2002 and a family dispute arose as to whether Ted had really wanted to be cryopreserved.

In 1983, Dr. Roy Walford, a life-extensionist gerontologist published a popular book called Maximum Lifespan. Later, Dr. Walford and his student Dr. Richard Weindruch, summarized years of their research into the ability of calorie restriction to extend the lifespan of rats in their 1988 scholarly work The Retardation of Aging and Dietary Restriction. It had been known since the work of Clive McCay in the 1930s that calorie restriction can extend the maximum lifespan of rodents. But it was the work of Walford and Weindrich that gave detailed scientific grounding to that knowledge. Walford's personal interest in life extension motivated his scientific work and he practiced calorie restriction himself.

In 1993 the American Academy of Anti-Aging Medicine (A4M) was formed to create an anti-aging medical specialty distinct from geriatrics, and to hold conferences for physicians interested in this field.

The most recent development in life extension has been the work of biogerontologist Aubrey de Grey of Cambridge University. Dr. de Grey proposes that damage to macromolecules, cells, tissues and organs can be repaired by advanced biotechnology.

Strategies of Life Extension

Anti-Aging Medicine

Much of anti-aging medicine has been concerned with the use of nutritional supplements to extend lifespan. Because of the free radical theory of aging it has been believed that antioxidant supplements like Vitamin E, lipoic acid and N-acetylcysteine might extend human life. Because diabetes resembles aging and is associated with cross-linking of proteins seen with aging, it has been believed that anti-glycating supplements like carnosine and lysine might reduce aging. Because natural hormones decline with age, it has been believed that restoring growth hormone, melatonin or dhea to youthful levels might be a means of restoring youth.

Calorie Restriction

Calorie restriction (CR) with adequate nutrition has been shown to extend the lifespans of almost every species on which it has been tested, including not only rats, but yeast, fruit flies and nematodes. Experiments are in progress with primates to show that calorie restriction can extend the lifespan of long-lived species. A mutual support group called the Calorie Restriction Society was formed with the help of Roy Walford in the mid-1990s. These people have the willpower and determination to restrict their caloric intake in the hope of extending their lives, but they are very few in number. They communicate by e-mail and have been flown to Washington University in St. Louis to be studied by Dr. John Holloszy.

SENS (Strategies for Engineered Negligible Senescence)

Dr. Aubrey de Grey believes that it will someday be possible for humans to live thousands of years in a youthful condition. He calls his project to reverse the damage we call aging SENS (Strategies for Engineered Negligible Senescence). He has seven strategies for the "seven deadly sins":

  1. Cell loss can be repaired (reversed) just by suitable exercise in the case of muscle, but for other tissues it needs various growth factors to stimulate cell division, or in some cases it needs stem cells.
  2. Senescent cells can be removed by activating the immune system against them. Or they can be destroyed by gene therapy to introduce "suicide genes" that only kill senescent cells.
  3. Protein cross-linking can largely be reversed by drugs that break the links. But for some of the links we may need to develop enzymatic methods.
  4. Extracellular garbage can be eliminated by vaccination that gets immune cells to "eat" the garbage.
  5. For intracellular junk we need to introduce new enzymes, possibly enzymes from soil bacteria, that can degrade the junk that our own natural enzymes cannot degrade.
  6. For mitochondrial mutations the plan is not to repair them but to prevent harm from the mutations by putting suitably modified copies of the mitochondrial genes into the nucleus by gene therapy. The mitochondrial DNA experiences so much mutation damage because most free radicals are generated in the mitochondria. If mitochondrial DNA can be moved into the nucleus it will be better protected from free radicals, and there will be better DNA repair when damage occurs. All mitochondrial proteins would then be imported into the mitochondria.
  7. For cancer (the most lethal consequence of mutations) the strategy is to use gene therapy to delete the genes for telomerase and to eliminate telomerase-independent mechanisms of turning normal cells into "immortal" cancer cells. To compensate for the loss of telomerase in stem cells we would introduce new stem cells every decade or so.

Dr. de Grey has created a Methuselah Mouse Prize which awards money to researchers who can extend the lifespan of mice or rejuvenate mice.

Cryonics

Cryonics is inspired by the fact that life extension technologies may eventually allow people to live thousands of years of youthful life. But these technologies may not be available to for another 50 years. There is a danger that anyone, including young people, may die before the new medicine becomes available. Cryopreservation shortly after legal death may provide an "ambulence" into the future. The assumption of cryonics is that at cryogenic temperatures there will be no alteration in biological tissue for thousands of years, which allows plenty of time for future medicine to achieve the required capabilities.

For those in cryonics, future medicine will not only be able to cure all disease and rejuvenate everyone to a youthful condition, but it will be able to repair any damage that is caused by the cryopreservation process. Molecular repair technology (nanotechnology and nanomedicine) is expected to be able to achieve these results. But to be safe, and to minimize damage, efforts are being made to eliminate all freezing damage through vitrification and to minimize ischemic damage through rapid cooling and cardio-pulmonary support immediately following pronouncement of death.

Scientific Controversy about Life Extension

Anti-Aging Medicine

Although Alex Comfort was an anti-aging gerontologist ahead of his time, other "old guard" biogerontologists vehemently deny that aging is a disease. Possibly the most prominent biogerontologist making this denial is Leonard Hayflick, who determined that fibroblasts are limited to around 50 cell divisions. Hayflick reasons that aging is an unavoidable consequence of entropy.

Dr. Denham Harman spent years experimenting with antioxidants, and was only able to establish that they can extend mean lifespan, but was not able to demonstrate an effect on maximum lifespan. In response to what they saw as unscrupulous profiteering by those engaged in the selling of supplements and the practice of anti-aging medicine, a group of prominent biogerontologists began a "war" on anti-aging medicine in general and the A4M in particular. Jay Olshansky,Leonard Hayflick, and Bruce Carnes wrote an position paper against anti-aging medicine that was published in Science magazine.

Calorie Restriction

Despite the results on yeast, fruit flies and nematodes, criticisms have been raised that the results of calorie restriction experiments on laboratory rats are invalid because years of inbreeding have made these animals different from those found in the wild. Even when it is conceded that the rat work may be valid, some argue that the results are only applicable to short-lived species because such species have evolved to respond to feast and famine with alterations in longevity. Proving that the results are valid is difficult, because experiments with long-lived species necessarily take a very long time to perform.

Despite thousands of scientific papers demonstrating the efficacy of calorie restriction on a wide range of animals, the subject is virtually never mentioned in nutrition textbooks.

SENS (Strategies for Engineered Negligible Senescence)

The SENS project is criticized as a pipedream based on pure speculation, rather than any proven science. Aubrey de Grey has been criticized on the grounds that he is a theoretician who does no empirical work himself. Yet Dr. de Grey has a phenomenal capacity to organize working scientists, to conduct scientific conferences, and to be editor-in-chief of the peer-reviewed journal Rejuvenation Research.

Cryonics

Cryonics is not current science, it is based on anticipations of the capabilities of future science. No mammal has been cryopreserved and brought back to life. Nonetheless, vitrification has made remarkable strides in eliminating freezing damage and maintaining viability of cryopreserved tissues. One is reminded of all the scientists who said cloning would be impossible not so long ago. Routinely journalists interview scientists who know nothing about cryonics and are told that it can never work because of freezing damage (being totally unaware that cryonics organizations use cryoprotectants). As often as not they display their ignorance by referring to cryonics as "cryogenics". The most often quoted phrase is that "believing cryonics could reanimate somebody who has been frozen is like believing you can turn hamburger back into a cow."

Ethics and Politics of Life Extension

Anti-Aging Medicine

Life extensionists commonly hear the accusation that they would destroy the planet with overpopulation. The conservative so-called ethicist Leon Kass has exemplified the anti-life extension view with this statement that:

"simply to covet a prolonged life span for ourselves is both a sign and a cause of our failure to open ourselves to procreation and to any higher purpose. … [The] desire to prolong youthfulness is not only a childish desire to eat one’s life and keep it; it is also an expression of a childish and narcissistic wish incompatible with devotion to posterity."

To a life extensionist the words of the anti-life extensionist as nothing less than the death-threats of fascists who have no conception of "live and let live" or of individual choices. Kass would use government power to ensure that no one's life is extended, whatever they may wish:

"the finitude of human life is a blessing for every individual, whether he knows it or not."

For years the FDA tried to destroy the Life Extension Foundation, through attacks by armed government agents, through seizure of merchandise and through court action. The FDA refused to regard aging as a disease or life extension as a valid treatment category. In 1991 Saul Kent and Bill Faloon, the principals of the foundation were thrown in jail and told by the FDA that would become the target of criminal indictments that would "destroy their lives forever" and were told to plead guilty of crimes against the state. Against the advice of all their lawyers, Kent and Faloon fought the FDA in court and filed countercharges concerning their mistreatment. In 1995 the FDA told Kent and Faloon that in exchange for a guilty plea they would not have to go to prison and could continue doing business on a more limited basis. Instead of pleading guilty, Kent and Faloon filed a new battery of legal motions, escalated their counterattack against the FDA and began extensive preparations for their trial. In November 1995, the FDA dropped all charges except the charge of "obstruction of justice" against Saul Kent. In February, 1996 even this charge was dropped.

SENS (Strategies for Engineered Negligible Senescence)

Technology Review, which is owned by the Massachusetts Institute of Technology, published an article in February 2005 that painted an unfavorable portrait of Aubrey de Grey, the man, supplemented with an attack on his science. The interviewer concluded that Dr. de Grey "would surely destroy us in attempting to preserve us" because living for such long periods would undermine what it means to be human. In an effort to destroy SENS, Jason Pontin (the magazine's editor) offered $10,000 to any gerontologist who could prove to an independent review panel that de Grey's ideas about radical life-extension had no merit. Dr. de Grey retaliated by matching the $10,000 and making the prize for debunking him a generous $20,000. So far there have been no takers.

Cryonics

As a life extension practice, cryonics has been under attack for many of the same reasons as the other life extension practices. Additionally, however, people are aesthetically revolted by the practice of cryopreserving "dead bodies" and especially of cryopreserving heads ("neuropreservation").

Almost from the beginning the Society for Cryobiology has attacked cryonics as being "fraud" and "quackery" and has banned cryonicists from being members of the Society. There are cryonicists who are members, but they are necessarily discreet about their affiliations. Most of the members of the Society have also made it clear that they have non-scientific grounds for their hostility, including the usual anti-life extension arguments as well as aesthetic arguments. Additionally, like many scientists, many of the Society members are simply conformists, who try to espouse beliefs that they believe are acceptable to their peers.

As a result of the Ted Williams media circus surrounding cryonics, a bill was passed in 2004 by the Arizona House of Representatives to place cryonics and cryonics procedures under the regulation of the state funeral board. In its original form the law would have prevented Alcor's use of the UAGA. The bill was withdrawn. Although it was not responsible for Ted Williams, the media circus resulted in the Cryonics Institute (CI) being placed under a "Cease and Desist" order by the State of Michigan for six months. Finally the Michigan government decided to regulate CI as a cemetery.

There are many people who hate cryonics and who hate cryonicists. The Ted Williams affair has become a focus of such people. A novel was recently written that portrayed a baseball star cryopreserved by a cryonics organization. The novel had the "happy ending" of a determined suicidal cryonics-hater flying an airplane into a cryonics facility -- destroying himself and everyone within the building.

See Also

External Links

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