Scientists doubt that extreme natural longevity is feasible. But if lifespan is ruled by a genetic ‘clock’, that view could change
The grim reaper comes for everyone in the end, but sometimes he is in less of a rush. This was certainly true for Sodimedjo, an Indonesian man who died on Sunday, but whether he was the full 146 years he claimed remains doubtful – not least because his purported birthdate is 30 years before local birth records began.
Scientists have their own reasons to be sceptical. A study published last year pointed to the existence of an upper ceiling on the natural human lifespan.
While the average life expectancy has steadily increased since the 19th century, data from the International Database on Longevity showed that the age of the very oldest people on the planet appeared to plateau in the mid-1990s – at a mere 114.9 years. Since the apparent plateau happened at a time when the reservoir of healthy centenarians was expanding, scientists concluded that an intrinsic biological limit had been reached: even if you evade accidents and disease, your body will still steadily decline until it passes the point of no return, the data appeared to suggest.
This raises the intriguing possibility that ageing could be slowed or even reversed, and some animal studies have already claimed to do just this.
Jan Vijg, a geneticist at Albert Einstein College of Medicine in New York City, who led this research, said: “We simply provided evidence that humans do indeed have a ceiling that they really cannot go beyond. That’s part of being human.”
There will be the occasional outlier – the French supercentenarian and oldest woman to have lived, Jeanne Calment, was 122 when she died in 1997, but most of us have a shorter intrinsic “shelf life”. The probability of someone living to 146 is infinitesimal, Vijg said. “If somebody told you that they saw a UFO yesterday but it’s gone now, you’d probably be polite, but you wouldn’t believe it,” said Vijg. “That’s my reaction with this story.”
Before resigning yourself to the knowledge that you will almost certainly expire by the time you reach 115 years, it is worth noting that this ceiling could be moveable in the future.
Richard Faragher, professor of biogerontology at the University of Brighton, puts it this way: “How long can a human live if you don’t do anything to them? Probably around 120. But there is a separate question, how long do people last if you can do something to them?”
Until now, the steady increase in average life expectancy (as distinct from lifespan) has been driven by fewer people smoking, better nutrition and antibiotics. Drugs and surgery for heart disease and cancer have also played a part.
However, scientists are only just beginning to explore the possibility of therapies designed to target the process of ageing itself, as well as the illnesses that come with advancing years. This field has recently taken an intriguing twist, as evidence has emerged that ageing is not simply the manifestation of environmental wear and tear. Instead, the latest work suggests that ageing is at least partly……….Read more here!
Courtesy of Guardian News & Media Ltd