topics: |  health | aging

In his book Advice to a Young Scientist, Peter Medawar suggests, "Study what
interests people." (on why he's looking at aging; preface)

1 The Paradox of Aging

Depth of human gullibility on claims of longevity

In Westminster Abbey, where England buries with solemn honor its greatest
poets, painters, scientists, and statesmen, lie the bones of one rather
ordinary man - Thomas Parr. A farmer's servant from Shropshire, Thomas Parr's
only claim to distinction is that he managed to convince a gullible
seventeenth-century public that he had been alive for more than 150 years.

Although Parr did manage to have himself interred among the
anointed paragons of English history, had he not made his claim to great
longevity, he probably would not have been dragged in from the provinces to
be exhibited before the king like an exotic plant from the New World. And if
he hadn't been so exhibited, he might not have caught the illness that, a
short time later, finished his mendacious history at the declared age of 152,
sending him straightaway to rest at Westminster.

[gullibility is not only part of the unsophisticated
gentry of the seventeenth century]

1966: Life magazine, for instance, published an article in 1966 on an area
in the Georgian Caucasus where people commonly claim to live for more than
100 years. focused on Shirali Muslimov, 161 years old at the time. He had
married his current wife when he was supposedly 110, and still seemed
hearty and energetic...  When he died seven years after the Life article
appeared, the news was reported around the world.

 October 1979: American newspapers reported that Charlie Smith, who claimed
a boyhood memory of being brought to the United States as a slave in 1854,
had died at the age of 137. Smith had a brief run in the Guinness Book of
World Records as the longest-lived human... television show...  But Smith's
claim was disproved shortly before his death when a marriage certificate
surfaced that he filled out when he was 35 years old in 1910. In truth,
Smith died at the respectable, though not unheard of, age of 104. 

Paradox of Aging: why growing older causes us to become fragile

It's apparent to anyone who cares to notice that the elderly live in a state
of relatively fragile health. And generally speaking, the more elderly they
grew, the more fragile they became.

In thinking that aging is as inevitable as, say, the passage of time, we are
committing what might be called the fallacy of the machine. That is, we
tacitly assume that our bodies are like machines that must inevitably wear
out. The flesh is assumed quite literally to be weak and doomed to eventual
failure.  However, living organisms are very different from machines. The
most fundamental defining character of living organisms, in fact, may be
their ability to repair themselves. We don't usually die of cuts, bruises, or
even broken bones. These injuries mend, and life goes on. Some animals
perform remarkable feats of self-repair. Tear a starfish in half, for
instance, and each half will regrow its missing half, so that you eventually
end up with two healthy starfish.

[Also, animals don't start out aging]
For the first part of our lives, for instance, we actually improve in
virtually every bodily function... p.4

Cancer cells can be immortal

Some cells in our bodies can achieve immortality, but only by turning
cancerous. 
For instance, in 1951 a few such cells were removed from Henrietta
Lacks, a terminally ill young woman from Baltimore. They have been
irrepressibly growing and dividing in laboratory culture dishes ever
since. Known as HeLa cells, they are now so numerous that they are used to
study the biology of cells in hundreds of laboratories around the world. But
normal cells, as opposed to cancerous cells, do not grow and divide
forever. In a similar laboratory dish, normal cells from, say, skin or lungs
will grow and divide for a time, then stop. So why can't "normal" cells have
the immortal properties of "abnormal" cancer cells? p.4

Differences in longevity:
dogs - speed through life in 15 years instead of the human 70. 

Measuring aging

As Lord Kelvin once rather pompously declared, "Until you have measured
something, you don't know what you are talking about." Of course, Lord Kelvin
is now famous for having deduced from the temperature of the earth that it
could be no more than a few hundred thousand years old, thus demonstrating
that even if you have measured it, you still may not know what you are
talking about. (present estimates: earth is 4.5 billion years old).

[Medawar's experiment on the life of test tubes in the laboratory]