One afternoon my daughter and I walked through the cemetery next to the parsonage in Haworth, the home of the Brontë family in Yorkshire. Densely packed tombstones mostly told the same story. Sibling after sibling from family after family buried long before they reached their 12th birthday. In 1850, a public inquiry into sanitation in the village revealed that the average life expectancy of its citizens was 25.4 years, not many months short of my daughter's age, victims of dirty water and inadequate sewage systems.

Two days after that visit, the Department for Work and Pensions published a study that predicted that babies born this year are 50 times more likely to become centenarians than those born 100 years ago. The bereaved parents of Haworth would have had many reasons to celebrate these years of extra time with their offspring, yet the overwhelming response to this achievement permitted by medical advances and improved living standards has been unmitigated gloom.

The expansion of the current figure of 11,600 centenarians to half a million by 2066 will allegedly cause "a budget time bomb", damaging the attempts to reduce the deficit and lead to a barren and bleak old age as pensions and benefits fall and a grey pall descends on a society addicted to youth. Of course, judging by today's prevailing image of senescence, it's easy to see why pessimism rules.

However, the future is a very different country. And a more positive frame of mind than the present collective near panic could count for far more than we realise in shaping its terrain.

On current statistics, it's understandable that the dominant question is: who would want to grow old and reach a vintage age? A million pensioners live below the poverty line; more than a million aged 65 and older report that they are often or always lonely; chronic long-term conditions such as diabetes and heart disease plague millions; public places make no concessions to the needs of the less agile while popular culture too often pushes anyone over 60 out of the frame unless he or she is attempting to pass as 20 years younger.

Individuals celebrating their 100th birthday today would be entitled to demand, as my great aunt did: "I'm a centenarian, get me out of here!" (Without any luck in her case – she died at 108.)

However, there is good news. Those who are octogenarians now were born into a society in which average life expectancy barely reached 60. They endured war, rationing, austerity and, frequently, many grafted hard in heavy industry for 30 years and more. They are the welfare state's first children and they were grateful for what they received, even though, often, it delivered less than it might have done to ensure their quality of life.

Now, we are on the threshold of a new era. We know much more about what can immunise us from the worst effects of ageing. Important elements are good health, a decent income and, perhaps most significant of all, robust relationships and connections to others.

Genes and good fortune help but so will creating a different kind of society. One in which the growing gap between young and old is challenged; the value of experience is properly appreciated and success is no longer solely defined by what you earn and what you spend.

Those changes might even turn my 26-year-old daughter's horror of the thought of potentially living for another 80 years to anticipation that she may be fortunate enough to experience not one life but several. In the US, for instance, organisations already exist that give truncated training to retirees who then take on an "encore" career, in a different field from their first, often working to give something back to the community.

In one sense, the future is already here. Since 1995, the New England centenarian study has been collecting the long-lived (and new recruits are welcome). Currently, the study is researching 1,600 centenarians and 500 of their children who are in their seventies and eighties. Around 85% of the original group are female, golden girls, perhaps because in the era in which they were young many of the vices were frowned upon: no fags or booze. (Although a study published of centenarian Ashkenazi Jews shows that drinking and smoking aren't always a barrier to extreme old age.)

The New England group vary widely in education, income, religion, ethnicity and patterns of diet (strictly vegetarian to saturated very fatty fats). However, they share a number of characteristics in common.

They are Jack Sprats opting to stay lean; they appear better able to handle stress and remain positive; and the women have often given birth late, after the age of 35. (Heartening, perhaps, for those who have delayed motherhood, who could be around to even see their great grandchildren flower.) In addition, if illness comes, it's often delayed until a person reaches their nineties, and they can make a strong recovery.

Living well, working for longer, staying active in a community in which you have family and friends doesn't seem to add up to all that costly an exercise for society.

On the contrary, it might reap the benefit of the presence of wiser minds and greater levels of contentment. (A study said older people are content because they can experience happiness without excitement, unlike the young.) In addition, as medical advances promise artificial organs and revitalised limbs and technology works to make mobility and independence easier for longer, the current prevailing nightmare scenario ought to be replaced by a common aspiration that we can and will achieve, for as many as possible, a "good" old age.

Embracing rather than fighting against increased longevity also requires society to exercise a lot more imagination than it has hitherto shown. Lunch clubs, meals on wheels, old people's homes and sheltered accommodation are all concepts born of their time, but desperately in need of an update.

Likewise, the curse of our age – isolation – also requires a more proactive attempt at a cure. An older person may begin adult life with friends; have his or her circle expand with a partnership, but then find that those ties are severed by death or divorce or circumstance.

So how do you forge new bonds in your seventies or eighties?

In Slapstick, a novel by the American writer Kurt Vonnegut published in 1976, Wilbur Swain runs for president, on the slogan: "Lonesome no more". His "big idea" is to create artificial families so that every one could have 10,000 brothers and sisters. It sounds like science fiction but then, at one time, only last year, so did the notion of a society with half a million centenarians.