X-Message-Number: 15161 From: "Mark Plus" <> Subject: "Who wants to live forever?" Date: Fri, 22 Dec 2000 08:34:21 -0800 From: http://www.economist.com/printedition/displayStory.cfm?Story_ID=457115&CFID=242716&CFTOKEN=72237059 Prolonging life Who wants to live for ever? Dec 21st 2000 From The Economist print edition Average life expectancy has risen greatly. The span of individual life has not. Would it be a good thing if it did? No ARE you hoping for a long life? Thought so. Are you looking forward to growing old? Thought not. Man has wanted one without the other for thousands of years, and has invariably been disappointed. Cleopatra is said to have bathed in asses milk to stay young and beautiful, but did not live long enough to find out if it worked in old age. The Spanish explorer Juan Ponce de Leon was more famous for his search for the Fountain of Youth than for discovering Florida in 1513. He never did find the rejuvenating spring that the natives had told him of, and died from a poisoned Indian arrow a few years later. The legend of the Fountain of Youth may have originated in northern India. It had reached Europe by the 7th century, and was widely known there in the Middle Ages. When Lucas Cranach the Elder was 74, he painted a famous picture of the miraculous spring, with wrinkled old women going in at one end and young beauties coming out at the other. Writers have constantly imagined worlds where people lived to prodigious ages while holding on to their youthful looks and vigour by various means, mostly foul. Oscar Wilde s Dorian Gray kept a picture of himself in the attic, on which his excesses were visited while he himself remained ever young and handsome though the arrangement, and Mr Gray, came to a sticky end. In the real world too, people are prepared to try all kinds of disgusting things, from mud baths to injections of monkey glands, in the hope of staying younger longer. If only You might think they no longer needed to bother. People today generally live much longer than ever before. Neanderthal man could expect to live to about 20. Things got better, but only very gradually: by the middle of the 18th century AD, in Western Europe, life expectancy at birth averaged about 30 years. Now, that figure for the world as a whole is about 65, thanks to the past two centuries improvements in living conditions, public health and medical care. A baby born today in affluent North America or Western Europe can expect to live to 75-80. He (or she) has an excellent chance of avoiding heavy and prematurely ageing manual labour, and enjoying a comfortable lifestyle. His biggest problem will probably be to resist the temptation to eat too much, exercise too little and become obese. But if he looks after himself, he should remain in fair shape for most of his greatly extended time on earth. Lengthening lifespan Yet, though life expectancy has risen sharply, in quite a short time, the individual human lifespan set by nature has remained much the same through most of recorded history. It was even if mainly in theory three score and ten in Biblical times, and it isn t much more now. Most people died of one thing or another long before their allotted span was up. Even in the depths of history a few people lived to a great age. Researchers reckon that Rameses II, who ruled ancient Egypt some 3,250 years ago, may have survived into his 90s. So did the Greek dramatist Sophocles 800 years later (and, to judge from some of his late writings, felt it quite long enough). His countryman and near-contemporary, the philosopher Plato, who lived to 80, shrewdly pointed out one reason for such unusual longevity in The Republic . An old man is told by a younger friend: I rather suspect that people generally think old age sits lightly upon your shoulders, not because of your cheerful disposition, but because you are rich. Wealth is known to be a great comforter. The big achievement of modern times is that, in developed countries at least, most people are now well enough off to reach the age they were designed for. No longer do they die in large numbers in the first year of life, or later from infectious diseases, or suffer malnutrition, or work themselves to death (except in Japan, where karoshi, suicide due to overwork, is a familiar end; but at least it is voluntary). Barring accidents, therefore, most people now go on until they die of one of the afflictions of ripe old age, such as cardiovascular disease or cancer. Britain s queen now sends out ten times as many congratulatory messages to centenarians as she did when she came to the throne nearly half a century ago. But although on average people in affluent countries now will live far longer than their equivalents even a century or two ago, individual lifespans will not be huge by historical standards. Granted, there are regular reports of healthy 130- or 150-year-olds being discovered in some remote mountain region in Eastern Europe, living on yogurt and garlic, herding goats and fathering children at an age when most people would have been dead long ago. But invariably the evidence to support their claim turns out to be less than solid. The oldest documented person in history was Jeanne Calment, a Frenchwoman from Arles, who died in 1997 at the age of 122 years and 164 days. She was old enough to have met Vincent van Gogh, in her younger days (or so she said he never painted her). By all accounts she remained reasonably fit and compos mentis until quite close to her death, and appeared to enjoy her long life. Longer health, not just longer life The current emphasis in age research is on what experts call compression of morbidity : finding ways to ensure that the rising number of people who achieve the apparent maximum lifespan do so in tolerable health, not just after extra years of decrepitude. Much of the advice handed out is simple common sense: adopt a healthy lifestyle, eat and drink in moderation, do not smoke, take regular exercise but don t overdo it. These rules are often flouted, sometimes without apparent ill effect. In a speech at his 70th birthday celebration, Mark Twain outlined his own survival strategy: I have made it a rule to go to bed when there wasn t anybody left to sit up with; and I have made it a rule to get up when I had to. In the matter of diet, I have been persistently strict in sticking to the things which didn t agree with me, until one or the other of us got the best of it. I have made it a rule never to smoke more than one cigar at a time. As for drinking, when the others drink I like to help. I have never taken any exercise, except sleeping and resting, and I never intend to take any. Exercise is loathsome. He lived to 75. In 1910, that was much longer than most Americans. But even for those who stick to the rules, all that a healthy lifestyle can do is to improve their chances of staying in reasonable shape for their age; it will not slow down the ageing process. Nor yet, for all the hype for this hormone treatment, that vitamin supplement and yonder course of injections, would any of the patent remedies so widely and profitably peddled. The only experiments on laboratory animals that have definitely shown a life-lengthening effect have involved subjecting rats and mice to a severely restricted diet. The less they eat, short of actual starvation, and the longer they go on doing so, the longer they live. But they have less fun than rodents on a normal diet. Ravenous rats reproduce less, and ravenous mice not at all. Whether that method would work on humans, no one knows. They are so long-lived that any experiment would have to continue for many years to prove anything. Getting enough volunteers, and preventing them cheating, would prove mighty difficult. And suppose that severely restricting food intake did indeed make people too last longer? If their urges also turned out to be affected like those of rodents, what a great life it would be and extra decades of it. That, in Greek myth, was the fate of Tithonus, lover of Aurora, the dawn: he asked for immortal life, and got it but he d forgotten to ask for youth as well. Poor Tithonus, poor Aurora A different approach might work. To some extent longevity is an inherited trait. Experiments with that old friend of science, the fruit fly, have shown that selective breeding for long life can produce significantly longer-lasting flies. But again, that would not be much help to humans: we have long life-cycles, so the results might be centuries ahead even were we ready to choose potentially long-lived mates rather than visibly well-endowed or well-heeled ones. What, though, if instead of selective breeding for longer-lived stock, the chosen method were to be genetic manipulation? Now that the sequencing of the human genome has been completed, all sorts of gene-therapy treatments are beginning to look possible. The process of ageing is a complex matter in which many different genes appear to be involved, but in time it may become possible to use gene therapy to slow down ageing, if not eliminate it. Accidents will happen Not that, even if ageing could be stopped altogether, people would stop dying. Accidents will happen. Age researchers reckon that if people were able indefinitely to preserve their maximum health and vigour (which in developed countries is reached around the age of ten or eleven), they would on average live for about 1,200 years; while one in about 1,000 would last for 10,000 years. He might get a bit lonely as all his friends bowed out. In the end, though, the incidence of death for mankind as a whole would still be the same as ever: 100%. Life is an invariably fatal disease. Meanwhile, having individuals around for hundreds or even thousands of years would require some radical adjustments. Even without such innovations, the latest UN estimates suggest that, on fairly conservative assumptions about birth and death rates, today s world population of just over 6 billion may rise to 8.9 billion by 2050; by when, instead of today s 600m people over 60, there will be about 2 billion roughly one in four of all mankind, worldwide, and in Europe nearly 40%. And then? If people were to live a lot longer, and everything else stayed the same, old people would soon end up in a huge majority. Ugh. Demographers reckon the planet will have trouble handling just the 8.9 billion forecast for 2050. Even were there shelter and food, these hordes of super-oldies would face a grim life, unless they could survive without vast extra medical care, and remain fit enough to go on and on working, to avoid having to be maintained by the dwindling, resentful minority of younger people. Who wants it anyway? A world of seen-it-all-before, weary crumblies would be a depressing place to live in. As Cicero wisely observed in Rome more than 2,000 years ago: It is desirable for a man to be blotted out at his proper time. For as nature has marked the bounds of everything else, so she has marked the bounds of life. Moreover, old age is the final scene, as it were, in life s drama, from which we ought to escape when it grows wearisome and, certainly, when we have had our fill. _________________________________________________________________ Get your FREE download of MSN Explorer at http://explorer.msn.com Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=15161