Extending Human Lifespan
Extending human lifespan has become a buzzword in Silicon Valley, as billionaires
and biotech companies compete to create age-defying drugs vnreporter. In addition to the Palo
Alto Longevity Prize launched by hedge fund manager Joon Yun, there are a number
of organisations dedicated to this mission.
The dream of living forever stretches across human culture, from the Greek myths
and alchemical notebooks to modern movies and science-fiction books. Yet, as
geroscience progresses, it has become increasingly clear that a maximum lifespan
for Homo sapiens is unlikely to be exceeded.
Moreover, the vast majority of people living in developed countries now enjoy fairly
healthy lives, with most dying of old age at an earlier and shorter stage than a
century ago. This is a result of the enormous advances made in the 19th century,
when vaccines and sanitation helped to dramatically reduce infant and child
mortality.
Many other factors contribute to a lower life expectancy, including infectious
diseases, poor nutrition, accidents and age-related chronic disease. In addition,
some individuals have genetic variations that increase their risk of death.
However, some genetic variants also help to extend human life span by reducing the
risk of certain diseases, including cancer and diabetes. Ecuadorians with a rare
mutation in a protein that regulates growth signaling have been found to have much
lower rates of these illnesses than other people.
These findings, combined with evidence that a nematode worm’s lifespan can be
greatly increased by a single mutation in its genetic code, have led to the idea that
it is possible to extend the human lifespan by modifying a biological process. The
mechanism behind this is still unknown, but some ideas suggest that a calorie
restriction (CR) strategy may be involved.
As a rule, the lifespan of mammals is determined by several different factors,
including environmental conditions and genetics. For instance, the tortoise and
bowhead whale can live more than twice as long as humans; a Greenland shark has
been known to live over 100 years; and rockfish have been recorded to live for up to
600 years.
This is not the case for all species, and a wide variety of strategies have been
adopted by other creatures to reduce their risk of death, either directly or by
avoiding specific environmental hazards. These include avoiding parasites and
infections, improving nutrition, ensuring adequate levels of oxygen in the blood and
limiting exposure to toxicants, such as lead and other heavy metals.
Nevertheless, it is a fact that the average lifespan of most species has declined over
time. In some cases, this is a direct result of extinction events or predators. In other
cases, it is the result of the emergence of certain diseases that increase the risk of
death, such as typhus and cholera.