Judi Dench is old — 72 — and Helen Mirren, 61, is not exactly in her first flush. Diane Keaton is knocking on a bit, also 61, and Julie Christie, 65, is no spring chicken. Mick Jagger is famous for, among other things, being 63, and Bob Dylan, at 65, is well qualified to sing, as he does, about impending oblivion. If you like these people, admire them, identify with them, then you’re probably old, too.

You will find this hard to accept, if you, like them, are a baby-boomer, a unit in the population bulge that followed the second world war. Baby-boomers are the most privileged demographic cohort in history, and the deluge of material rewards they enjoyed convinced them, sometime in the 1970s, that they could do something about death — even that it might be optional. From Jane Fonda workout videos to Nivea DNAge, and now the film Wild Hogs, in which suburban boomers take to the highway on motorbikes, the boomers have sought the fountain of youth with increasingly desperate enthusiasm.

Their primary tactic, however, was not exercise, face cream or leather gear. It was denial. As the boomers aged and took over the commanding heights of the arts and media, they became ever more obsessed with youth. In spite of the fact that the boomer bulge meant the population as a whole was ageing, they persisted in pretending their entire target market/audience was aged between 18 and 35, and — wishful thinking this — rabidly sexually active. It was this demographic delusion that, presumably, persuaded the BBC that Moira Stuart, 55, was too old to read the news.

Now, this elaborate ritual of denial has been passed on to the next generation. Marketers have now defined a new age sector as “middle youth”. “It’s essentially a name for the age demographic of 30-45, which is refusing to conform to the traditional ‘middle-aged stereotype’,” says Zoe Lazarus, of the marketing consultancy Lowe Worldwide. “The traditional ‘view from the kitchen window’ approach to marketing to women in this age group is becoming less appropriate to a generation that still wants to be seen as energetic, youthful, stylish and sexy.”

So, denial is just a river in Egypt after all. But, in fact, straws in the wind suggest things might be changing. The boomers might be about to do what they have never done before — face facts. Dench, Mirren and Keaton, for example, are boomer heroines who have all defiantly asserted their age. In particular, in the 2003 film Something’s Gotta Give, Keaton diverted Jack Nicholson (70 next Sunday) from an obsession with young women, and in The Queen, Mirren played old age as a very special kind of triumph. Indeed, in doing so, she turned the real Queen (81 next Saturday) into a kind of boomer icon, an image of real, as opposed to merely cosmetic, survival. Presumably inspired by this, Alan Bennett, 72, has written a story entitled The Uncommon Reader, in which the Queen suddenly becomes an intensive and highbrow reader. It’s an odd conceit but, plainly, it is intended to redeem the condition of being old.

And now, Christie has returned to join these ranks of elderly heroines. In Sarah Polley’s film Away from Her, she plays a woman succumbing to Alzheimer’s. The particularly harrowing point here is that, physically, Christie looks superb. But it counts for nothing as her self dissolves into nothingness. Jane Fonda workouts won’t stop that. In addition, though Jagger and most rockers persist in acting like teenagers, Dylan on his three most recent albums has sung about ageing and death. His voice, which sounded old when he was 20, now sounds positively decrepit, though all the more magnificent. As Kazuo Ishiguro, 52, has observed, Dylan has once more gone on ahead, this time to romanticise old age. But, crucially, he has not done so by pretending it’s no different from youth. On the contrary, age is primarily defined as proximity to death. “It’s not dark yet,” he sings, “but it’s getting there.”

This highlights the central problem with facing the facts of ageing. As Dylan sings and Christie’s character shows, you can prance, dance and have as much sex as you like, but you’re still closer to death. This is more than just a statement of the obvious: it is a scientifically exact description of your predicament. For a long time, scientists had a problem with defining ageing — it happened at different rates in different people and manifested itself through different symptoms — but they finally arrived at a simple, statistical statement. Ageing is the increasing probability of death. Every eight years, you are twice as likely to die. There is no gainsaying this or exercising your way out of it. It is how life-assurance companies make money.

For some — notably advertisers — this makes acceptance impossible and drives them to ever more refined forms of denial. “Middle youth” is straight denial, but when that becomes impossible, there is the phoney celebration of age. Both Fonda and Keaton now appear in L’Oréal ads, but their role is to insist that you can look young in old age, rather than simply good at any age. L’Oréal’s cretinous slogan — “Because you’re worth it” — has never seemed so poignantly challenging, demanding the wry follow-up, “Why, when I’m almost dead?”

This is the dirty little thought that haunts the still youth-centred culture. It was brilliantly parodied by Chris Morris. In a spoof news broadcast about a bomb in Oxford Street, he dismissed the victims with the words, “Being old, they would have been dead soon anyway.” And, in countless television shows, the old are portrayed as the one group about whom it is possible to be relentlessly and personally cruel. Proximity to death means you and your feelings matter less.

The — in marketing terms — gigantically successful response to this has been the promotion of Dove products, first in the form of the Campaign for Real Beauty and, latterly, as being not antiage (the usual descriptive formula for utterly ineffective cosmetics), but “pro-age”. Discussed in editorials and on The Oprah Winfrey (53) Show, this has succeeded in highlighting the whole proximity-to-death issue.

In its pro-age form, the campaign, by Annie Leibovitz, 57, involves shots of naked old people. This proved too much for the Federal Communications Commission in the USA, which banned the television version of the ads, ostensibly on the grounds that they breached the FCC’s “implied nudity” regulation. However, Susie Orbach, visiting professor of sociology at the London School of Economics, insists it was because they couldn’t stand the idea of elderly nudity.

Orbach was one of the academics commissioned by Dove to provide a respectable basis for the campaign. Their report, Beauty Comes of Age, said that women over 50 wanted a change of view on women and ageing, that the media must cease its misrepresentations, and that they “want to be specially considered when health and beauty manufacturers are creating products for women”.

“The central issue for older women,” Orbach tells me, “is invisibility.” The intensive sexualisation of society by the media — particularly the use of the young female body — means that identity itself has become dependent on physical attractiveness. Just as the self afflicted by Alzheimer’s dissolves, so the ageing self dissolves as its body loses the ability to attract the attention of the young. Men can get away with distinguished, says Orbach, but women are forced to be too heavily dependent on mere youth.

Of course, Dove itself is no different from hundreds of other products. All that is different are the values Unilever has chosen to attach. “In a product category where there is little differentiation between individual brands,” says Lazarus, “it is clever of Dove to recognise that aligning yourself with a shared attitude of specific cause is a great way to build loyalty and, of course, generate column inches.” The campaign, promoted on giant billboards in big cities, is said to have added $1.2 billion to the value of the brand. But has it added anything to the value of age?

Almost certainly not. Advertising and marketing continue to be dominated either by middle-youthers who think they are still young or by baby-boomers who think they invented and own youth culture. Charles Saatchi, 63, will still race around Hoxton looking for young talent, women will still get Botoxed, and men will continue to apply Grecian 2000. About $13 billion worth of antiageing cosmetics are sold annually. Even Robert Mondavi, the winemaker, has joined in, with Davi’s Le Grand Cru Face Cream, $175 for 2oz. It’s full of grape-seed extract, apparently. People may pay lip service to the dignity of looking their age, but, when the chips are down, youth is the only game in town.

Yet the arts may — should — go some way to changing this. The London and New York gallery owner Bernard Jacobson specialises in older, living masters. “They are more patient and humble, also less desperate somehow. I suppose they’ve seen it all before,” he says. This kind of insight hints at the possibility that, even if boomers have trouble accepting death, they can at least embrace some form of maturity. For me, 55, two phenomena suggest this may be possible. The first is Stephen Frears’s film The Queen. This is partly because of the power of the Queen herself as an emblem of survival against all the odds — the misbehaviour of her boomer children included — and partly because of the way Mirren, always a highly sexual actor, so decisively took the role far beyond mere impersonation and into a realm where it was possible to see old age as distinctively meaningful.

The second is Dylan’s renaissance as the supreme contemporary artist of old age. His new songs accept that proximity to death is a terrible, intractable predicament, but they deliver wisdom from within that predicament, not by concealing or denying it. Both Mirren and Dylan are supreme boomer heroes. They lived the life and are now romanticising old age as something utterly distinctive, and, as far as the boomers are concerned, new.

Life expectancy at birth in Britain is now 77 for men and 81 for women. For the boomers, it’s not dark yet, but they’re getting there. With luck, wisdom, though a long time coming, will get there first.

Bob Dylan’s tour is at Wembley Arena tonight and tomorrow; Away from Her opens on April 27; Alan Bennett’s The Uncommon Reader is published on September 6 (Faber and Profile £12.99) www.bryanappleyard.com

Explore Women

• Fashion

• Beauty

• Diet & Fitness

• Relationships

• Families

• Celebrity

• Body & Soul

• The Way We Live

Times recommends

• Does your property need a pick-me-up?
• Love, the Saudi way
• Your 50 most asked travel questions