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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