THE HUMAN CONDITION For years we take our bodies for granted. And then it starts to happen. First the fat appears, then it spreads. Blemishes come but don't go. We lose hair where we want it, and grow hair where we don't. No one wants to get old, so whating about?
it could be said that the art of ageing gracefully relies on a philosophical acceptance of one's own mortality. It's increasingly hard in a society where youth is the prized commodity and the media and beauty industries encourage us to look younger and more perfect. Luckily for the health and beauty industry, very few of us ever look younger than we are. There is an enormous market for the abundance of products and techniques available. From face-creams to face-lifts - all promise the temporary illusion of immortality.

No one is totally immune. Take Fay Weldon, now 63, who recently told the Mail On Sunday about her predilection for cosmetic surgery. Having had the folds on her eyelids lifted and her upper face tightened, she is now tempted to have her jaw line redefined. "Age is like being born with a large nose," she says. "We feel duty bound to put up with it, but when plastic surgery is available why should we? We should take advantage of every possibility that medical science offers. I certainly have." She is not alone. Other high-profile personalities such as Jane Fonda, Shirley Conran and, according to one American magazine, Hillary Clinton, have also sought a younger look via the surgeon's knife.

Of course age doesn't only affect those in the public eye. For many people, the approach of middle age can be a period of self-doubt and reassessment. Psychologist Dr Eric Rayner writes in his book Human Development: "Somewhere about the age of 40, a person often begins to realise that life is half over for him. When a person looks equally backwards and forwards, he is aware of middle-age. There is also a recognition of physical ageing in his body organs. This deterioration is the basis of mid-life as much as growth was in the earlier years."

And it's not just middle age - for many people the first major watershed age arrives at 30. When psycho logist and author Dr Dorothy Rowe interviewed case studies for her book on ageing, Time On Our Side, (HarperCollins, pounds 6.99) she noticed that anxieties about age often seemed to culminate towards the end of each decade. "People nearing their thirtieth birthday would always tell me about how they saw it as a milestone and a turning point. Once they survived this, then their fortieth year represented doom and disaster. There are so many expectations built into these ages - like the older you get, the less valuable you are. The danger of thinking like this is that it can turn into a self- fulfilling prophecy."

After 20, it's true for most people that any birthday ending in a zero is going to be, at the very least, mildly traumatic. "I'd been dreading 30 since about the age of 28," says Sophie, a market researcher. "Suddenly I was aware of all these irreversible physical changes; deeply indented lines on my forehead and round my mouth. I knew I was starting to look more like my mother, which I think a lot of women feel towards the end of their twenties."

For Bill, a 39-year-old lecturer, the prospect of reaching 40 in six weeks time is, he admits, grim. "I know I should feel full of experience and wisdom and that should be the positive side of living half your life out," he says. "But at the moment I question everything: how I look, where I've got to in my career, how younger people I teach must view me. I actually feel less sure of myself than I did just a year ago when my identity was grounded in being a thirtysomething."

There is, however, a sickening select few for whom the transition from youth to adulthood and beyond doesn't seem to be a problematic issue. At least this is what Dr David Weeks, a clinical neuropsychologist at the Royal Edinburgh Hospital, has discovered through his 10-year project researching lifestyles and attitudes of the superyoung looking.

Three-and-a-half thousand people, between the ages of 30 and 101, have taken part in Dr Weeks's survey. He advertised in the media for subjects, asking them to send in a recent photograph. An independent panel was shown photographs from a control sample and the study group, then asked to guess their ages. The superyoung were perceived to be on average 12 to 14 years younger.

When Dr Weeks compared lifestyles of the youthful-looking with those of his control group, monitoring anxiety levels, well-being, religious belief, health, marital status, sex life and so on, he found the superyoung are more likely to take regular exercise, enjoy a vigorous sex life and have parents who are healthy and active in their old age. "Some of these findings don't make easy prescriptions," he admits. "And some of it does have a genetic ring to it. The women tended to have fathers that were older than those in the control group."

A happy disposition is another key factor. "The happiest people are less likely to be neurotic and more likely to look younger," says Dr Weeks. "Anxiety is likely to add years to your looks. One of the findings from the group is that they avoid the sort of stress that can be converted into depression. They also tend to avoid anger."

Understandably, they seem like a smug bunch. "They seem to have the confidence not to pay attention to how other people perceive youth," explains Dr Weeks. "Also they're more likely not to be scared of dying and have some kind of acceptance." He hopes that his survey will provide pointers for behaviour that may "retard the ageing process". "We talk about the mind in a metaphorical way and I'm trying to explore those connections between mind and body. It's kind of like the positive aspects of psychosomatic medicine." But most people find it impossible to avoid the anxiety that accompanies the physical effects of ageing. "I just don't believe those people that say age doesn't worry them," says 60-year-old Margaret Snook, who is often told that she looks 10 years younger. "It's human nature to worry about those watershed ages, regardless of how you look, and to feel you've got less time left. It seems to go faster."

In a recent interview with Ikon magazine, Martin Amis expressed a similar sentiment: "You don't know anything about the second half of your life until you're in it and it seems to be ushered in with this sudden feeling that time is running out and you're definitely for it ... There's the way girls in the street look completely through you. You don't snag on them any more. You're an invisible entity."

Invisibility, according to Dorothy Rowe, is a major factor in the fear of growing old. "Unless you're a rich old man, you do become invisible. People just don't see you," she says. This is especially true for women. "The ones I spoke to felt that it was an unspoken and universal rule that they were valuable only for so long as they were sexually attractive." Hence the appeal of cosmetic surgery. But the decision to choose it is as good as saying: "I won't be acceptable if I look as old as I am. I may even be ignored."

Perhaps this is what distinguishes Dr Weeks's superyoung set. One of his subjects commented: "I never worry about getting older and how other people judge me. I couldn't care less if men don't find me attractive. As far as I'm concerned, that's their bad luck."

But her confidence, shared by many of the others in the study, may not be so easy for the rest of us. As age discrimination becomes a social and maybe even a legal issue, the proposition that plenty of sex, exercise and a long-term relationship may make us feel and look younger seems a little simplistic. At the very most, it may make the decline toward the inevitable more bearable.

Suzette Scoble, deputy editor, 31: "Until I was 26 I thought I would never get old. Then between 27 and 31 I started to see real physical changes, lots of little things: my skin texture feels much softer, the bottom bit of my back has got larger. I'm distressed by the way cellulite seems to spread. It started at the top of my legs and now it's travelling downwards. Tiny spider veins are appearing, there are more lines under my eyes and I don't seem to have so much energy as I did in my twenties. The idea of ageing bothered me until about a year ago. Now it really doesn't. In terms of appearance, I don't feel so competitive. Five years ago if someone asked me to the pub I'd have to curl my eyelashes, put on lip liner and lipstick. Now I'll just grab my coat and I'm ready."

Phil Lau, graphic designer, 30: "I didn't like the idea of turning 30 so I went away for my birthday. I was quite worried about it and didn't want many people around me. Physically I think I look very young, I feel very glad about that. The only handicap is that people often only see the surface and don't expect you to be as experienced as you are. It hit me how old I was at 27 when I went back to college as a mature student. A lot of my friends were 19 or 20 and to be honest, I couldn't keep up with the pace. As far as feeling good is concerned, the early twenties are the best. I had more energy, physically I was on top form. The good thing now is that I really don't care what other people think about me. I feel a lot more secure, I'm not out to impress anybody."

Leslee Wills, teacher, 42: "I've definitely noticed physical changes. I used to lose weight much more easily, but now I don't seem to burn up the calories like I used to. There are hairs on my chin which I pluck out, and if I get a spot it takes much longer for the mark to go away. I must admit, I don't have as much energy as I used to. My 28-year-old boyfriend always wants to go to the cinema, then a restaurant, then on to a disco. The last one I went to I nearly died! But I don't feel old, perhaps because of my family. Being creative and in control was very much encouraged and I think this has kept me feeling young. I feel more positive about achieving goals. From experience, I know the way to get things done more efficiently. I feel as though I've become more powerful - I really do what I want to."

Jonathan Izard, Melody FM radio presenter and author, 40: "Looking back at my twenties, I associate them with neurosis, fear and pressure from other people. In your thirties there's more self acceptance and I see that continuing into my forties. There's an awareness of certain physical changes - I'll never have a full head of hair again. But I'd rather be someone who accepts that, rather than combing their hair across and trying to pretend. I don't look in the mirror and worry that I look older. I notice the odd new line but I think that looks quite nice and interesting. In terms of appearance, I like the fact that what you see is what you get. I think my face represents my character more than it ever has done. I used to be very critical about the way I looked and endlessly try to change myself - growing a moustache, a beard, wearing my hair long, then short - now it seems such a waste of energy. I'm happy with who I am now and I think that shows. One thing about reaching 40 is becoming aware of your own mortality. You think certain things have passed you by or if they haven't, you'll have to hurry - I want to learn to fly and I know I can't leave it for too long now. You really have to focus on what you want to do."

Tony March, design director, 51: "It's been a gradual realisation that I've been changing from year to year. I've put on a bit of weight, even though I still try to stay fit and I certainly can't drink as much as I used to. I've noticed a decline in my fitness as I've got older. I've always played a lot of sport but the injuries you get now seem to last longer than they did 20 years ago. At the moment, I've got a problem with my neck and visit a physiotherapist. Another thing is your sight gets worse. I find staring at a machine all day far more tiring than it used to be. I think there is a sub-conscious pressure that younger people seem to be able to cope with things better in terms of technology. It's always on my mind that at my age I just wouldn't get another job. The advantages are that I feel more experienced and confident about life. Marrying late and having young children has been something I could never have appreciated in my younger years."

Caroline Coon, artist, 50: "The older I get the happier I am. I think I look much better than I used to. In my twenties and thirties, I never felt beautiful and always thought my looks were a great disappointment to people. Feeling more attractive has everything to do with an increased self-confidence and nothing to do with how I actually look. Also, as I've got older I really don't care what people think about me. I feel very young in myself. I still stay up partying and drinking. If anything I can do it better now than when I was young. I'm more in control and I know how to pace myself. The other great bonus is experience. I feel so much more confident now than I did in my thirties and forties. As an artist I'm sure of my skills and am able to put what I've learnt into practice. Emotionally, I know my own insecurities now. I don't get depressed in the same way that I used to. Nowadays, when despair descends I know it will pass."

n Regular exercise: but not necessarily a punishing aerobics burnout. Brisk walking, badminton, rowing - the superyoung do it regularly from an early age.

n Regular sex: not a substitute for the exercise quota. An active sex life is high on the superyoung shared activity list. "This is very much a personal preference," says Dr Weeks. "I wouldn't wish to say people should have vigorous sex lives if it's not for them."

n A committed relationship: Again, not available on prescription. A secure and loving partnership seems to provide the superyoung with a feelgood factor associated with stability and self-assurance.

n Avoiding stress: Think positive. Avoid self-pity, doubt and anxiety, especially on or approaching birthdays that end in zero.

n Socialising: The superyoung tend to be outgoing and mix with a variety of age groups. Finding a toy boy or girl may well help - the superyoung are more likely than the general population to enjoy the advantages of an "age-gap" relationship.