The
Times - CHILDREN born this year may be able to live beyond
the age of 130, according to trends revealed by a new study
of ageing.
The age to which human beings can live is increasing by
more than a year every decade and shows no signs of reaching
any biological limit, American scientists have discovered.
If
the trend continues, a handful of children born in 2000
are likely to survive to the age of 130. The advance of
the human lifespan may even prove more rapid still, given
advances in medical science.
The
study, published in Science, used the world's most complete
set of population statistics from Sweden to measure for
the first time the way in which the human lifespan has
changed over the past 140 years. The Swedish figures follow
similar patterns in other industrialised countries such
as Britain and the United States, for which the data is
less reliable.
The
results contradict the long-held scientific orthodoxy
that the human body is incapable of living much beyond
120 as the organs give out through wear and tear.
John
Wilmoth, Professor of Demography at the University of
California at Berkeley and head of the research team,
said that the trend towards longer lifespans was accelerating.
Were there a natural limit, the rate would be expected
to slow as it approached.
"We
have shown that the maximum lifespan is changing,"
he said. "It is not a biological constant. There
is no hint yet that the upward trend is slowing down.
There is no scientific basis on which to estimate a fixed
upper limit. Whether 115 or 120 years, it is a legend
created by scientists who are quoting each other. Those
numbers are out of thin air."
Professor
Wilmoth found that in Sweden the average age at which
the oldest few per cent of people died was about 100 in
1860, when records began. By the late 1960s, that average
had risen to 105, an increase of just over five months
for each decade.
In
the 1970s, advances in medical care led to a sharp upturn
in the human lifespan. The average maximum age has now
reached 108, and is increasing at just over 13 months
per decade.
On
that trend, the average maximum age would reach about
121 by 2120, and the very oldest might be able to live
a decade longer than that. The oldest person whose date
of birth has been confirmed, Jeanne Calment, a French
woman, died in 1997 aged 122 and five months - 14 years
above the average maximum.Rising maximum ages can be attributed
to improved public health and sanitation early in the
20th century, and to modern drugs and medical techniques
developed since the 1970s, Professor Wilmoth said.
Further
medical advances, particularly those associated with greater
understanding of the human genome, could prolong life
still further. Last month, researchers at Manchester University
have developed drugs that make microscopic nematode worms
live 50 per cent longer than normal, raising the prospect
of treatments to fight ageing.
Life
expectancy, which measures the average age of death of
whole populations, rather than just the few who die latest,
is at present 74 for men and 79 for women in Britain.
Though women also have a higher maximum age than men,
the gender difference is much less pronounced.
There
are currently about two dozen documented cases around
the world of people more than 110 years old, Professor
Wilmoth said, and the numbers are likely to increase.
Britain is expected to have 30,000 centenarians by 2030,
compared with 271 in 1951.
The
British charity Research into Ageing said: "This
is an interesting and intriguing piece of work. It underlines
the need for medical science and healthcare to develop
to make sure that these extra last years can offer a high
quality of life."
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