Giorgione painted La Vecchia around 1509, but how old was his model, or indeed Shakespeare's for the seventh rung of decline into "sans everything"? A woman of 40 during the renaissance and an Elizabethan man of 50 might well have looked ready for one of today's residential homes. The greying of the population scares governments, which are daunted by the health and welfare implications and call, too late, for self-help. The response from the Blair government to the recent royal commission on the long-term care of the elderly has been, "thanks, we'll think about it". No good saying "we can't afford it". Old people may lose their faculties but they will never be "sans vote".
Gerontologists study the biology of ageing while geriatricians (and now politicians) specialise in the consequences. Tom Kirkwood is one of the former breed but reckons that more can be done to lighten the workload of the latter. Even so he thinks that expectation of life will go on increasing. In England and Wales, in Victorian times, it was two to one against survival to age 65; today it is bad luck if you die before you can collect a pension. Soon telegrams from the Queen will have to be restricted to those who make 110 - and so we go on.
The oldest reliably documented age at death is that of Jeanne Calment from Arles, France, who could remember Vincent Van Gogh. She died in 1997 at the age of 122. We can forget about those old men from Georgia in the former USSR. Kirkwood has a happy phrase for fictional ageing when official records are absent: the elderly "set the clock of their age too fast". Obituary writers encourage competitiveness, too, in a mild way. Death at 88 is just that but live a year longer and you will have passed away, more impressively, in your "90th year", not at a mere 89.
Not mentioned in this book is the rumour that Madame Calment stopped smoking in old age but then defiantly took it up again, a pattern, albeit anecdotal, that sits uncomfortably with Kirkwood's preventive thesis. But no one can argue convincingly for prevention until some myths about ageing have been dealt with.
Kirkwood's academic reputation was made at a time when he was not even in the field of gerontology, by his "disposable soma" theory of ageing (1977). This demolished the idea that ageing is biologically necessary and inevitable; nor is there some gene for mortality which switches itself on once a person's reproductive usefulness is over. This may sound non-Darwinian but order is restored by the theory itself: as we age, it becomes less and less efficient for our cells to repair the damage that chance and our bad habits impose. Our genes do get us in the end, but indirectly, via their sense of priorities.
Time of our Lives is an optimistic book published at a time when requiring old people to provide for themselves is the new political correctness. The sort of assistance from which Kirkwood's proposed preventative regimens would benefit is simple and cheap. Cells are equipped with the means to mop up unwanted, damagingly active molecules generated by oxygen but, if that system cannot cope, diet may help. For instance, some vitamins are antioxidants, and these are found in fruit and green vegetables. That senescence might be prevented by antioxidants is not a novel idea. I recall much excitement in the 1970s over animal experiments. Kirkwood adds other elements, of the oatmeal and exercise variety, but the important thing is that he is not offering the prospect of magical drug cures for ageing. For example, he is right-ly sceptical about the benefits of anti-dementia agents.
Kirkwood describes the theory well and writes entertainingly, a rare combination in a scientist. His book is a vital biological companion to the current debate on care for the elderly. But I was left unsure whether senescence can be avoided rather than merely postponed or, worse, prolonged. If it can, how will people die? In an odd epilogue, Kirkwood describes a world in which people live beyond 200. Once your reproductive quota is used up, a neurotoxin capsule is implanted that detonates at a preordained time, whether you like it or not. After a few days, that is that. The Bard's version of events suddenly sounds more appealing.
David Sharp is deputy editor of the "Lancet"