Eternal youth is the concept of human physical immortality free of aging . The youth referred to is usually intended to be in contrast to the depredations of aging, rather than a specific age of the human lifespan. Achieving eternal youth so far remains beyond the capabilities of scientific technology. However, much research is being conducted in the sciences of genetics which may allow manipulation of the aging process in the future. [ citation needed ] Eternal youth is common in mythology, and is a popular theme in fiction .
Religion and mythology
Eternal youth is a characteristic of the inhabitants of Paradise in Abrahamic religions .
The Hindus believe that the Vedic and the post-Vedic rishis have attained immortality, which implies the ability to change one’s body’s age or even shape at will. These are some of the siddhas in Yoga . Markandeya is said to always stay at the age of 16.
The difference between eternal life and the more specific eternal youth is a recurring theme in Greek and Roman mythology . The mytheme of requesting the boon of immortality from a god, but forgetting to ask for eternal youth appears in the story of Tithonus . A similar theme is found in Ovid regarding the Cumaean Sibyl .
In Norse mythology , Idun is providing good Described as the gods apples That grant eternal youthfulness em in the 13th century Prose Edda .
An individual’s DNA plays a role in the aging process. Aging begins even before birth, as soon as possible. On the ends of each chromosome are repetitive sequences of DNA, telomeres , which protect the chromosome from joining with other chromosomes, and have several key roles. One of these roles is to regulate the division of each division to a small amount of genetic code. The amount removed by the cell type being replicated. The gradual degradation of the telomeres restricts cell division to 40-60 times, also known as the Hayflick limit. This time has been reached, more cells can be replaced in the same time span. Thus, soon after this limit is reached the organism dies. The importance of telomeres is now clearly visible: lengthen the telomeres, lengthen the life. 
However, a study of the comparative biology of mammalian telometers indicated that telomere length correlates inversely, rather than directly, with lifespan, and concluded that the contribution of telomere length to lifespan remains controversial.  Also, telomere shortening does not occur with a certain postmitotic tissue, such as in the rat brain.  In humans, skeletal muscle telomere lengths remain stable from ages 23-74.  In baboon skeletal muscle, which consists of fully differentiated post-mitotic cells, less than 3% of myonuclei contain damaged telometers and this percentage does not increase with age.  Thus telomere shortening does not appear to be a major factor in the aging of the differentiated cells of brain or skeletal muscle.
Studies have shown that 90 percent of cancer cells contain large amounts of an enzyme called telomerase .  Telomerase is an enzyme that replenishes the telometers by adding bases to the ends and thus renewing the telomere. A cancer cell has in essence turned on the telomerase gene, and this allows them to have an unlimited amount of divisions without the telomeres wearing away. Other kinds of cells That can surpass the Hayflick limit are stem cells , hair follicles , and germ cells .  This is because they contain elevated amounts of telomerase.
The idea que le human body can be repaired in old age to a more youthful state HAS Gathered significant trade interest over the past FEW years, Including Such As companies by Human Longevity Inc. , Google Calico , and Elysium Health . [ citation needed ] In addition to these large companies, many startups are currently developing therapeutics to tackle the ‘aging problem’ using therapy.   In 2015 new class of drugs senolytics Was annoncé (currently in pre-clinical development) designed SPECIFICALLY to fight the Underlying biological causes of frailty. 
The “loss of youth” or aging process is responsible for increasing the risk of cancer , Parkinson’s , Alzheimer’s , and others. As a result, in recent years, many high net worth individuals have donated large amounts of money towards their initiatives towards scientific research into the aging process.  These people include Peter Thiel ,  Aubrey de Gray ,  Larry Ellison , Sergey Brin , Dmitry Itskov , Paul Glenn ,  andMark Zuckerberg .  This would allow humans to extend or maintain their youth indefinitely.
- DNA damage theory of aging
- Dorian Gray
- Elixir of life
- Fountain of Youth
- Indiafinite lifespan
- Peter Pan
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- Jump up^ “Esthechoc: Scientists invent ‘anti-aging’ chocolate .
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- Jump up^ Wallace, Benjamin (August 23, 2016). “An MIT Scientist Claims That This Pill Is the Fountain of Youth” . New York Magazine .
- Jump up^ “Billionaire Peter Thiel embarks on anti-aging crusade” .
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- Jump up^ “These Tech Billionaires Are Determined to Buy Their Way Out of Death”.
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