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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