Gone are the days when we could put youthful looks down to Oil of Ulay and an easy life. Weeks, a neuro-psychologist at Edinburgh University, now informs us, in his cod-scientific way, that there are several factors involved in being a member of the superyoung: "They drink the same as the rest of the population but smoke less and eat less meat." If this doesn't sound too bad, just you wait. "They are more altruistic, confident and sociable, and better-educated than the average person, and they have a more active sex life." Weeks claims that when his subjects had their ages hazarded by randomly selected "objective raters", the superyoung men were assumed to be on average 12 years younger than they really were; the superyoung women 10 years younger. Annoyingly, although Weeks points out that "the only objective quality of the superyoung is their appearance", the book contains no photographs, so The Independent on Sunday has tracked down some of the people who responded to Weeks's original advertisement.
Weeks draws a few facile conclusions ("Just saying you feel young is an essentially youthful - and, therefore, a potentially superyoung - thing to do") and the results aren't mind-blowing: it's not particularly surprising, for example, that people who live to exercise should look slightly less raddled than those who have spent a lifetime downing triple vodkas. Aside from their widespread belief that to slide serenely into a fireside armchair would be a shameful act of submission, what does emerge about Weeks's subjects is their delight at belonging to this elite. In the end, it's hard not to suspect that being superyoung has a lot to do with wishful thinking.
! Superyoung: The Proven Way to Stay Young Forever, by Dr David Weeks, is published by Hodder and Stoughton at pounds 9.99
ROBIN CLARKE, 44
I answered the advert more out of curiosity than vanity. It's a funny thing, but a lot of people are clearly surprised when they find out my age. I was late growing a beard, so I've looked young from the start, but now it's happening more and more. I'm 44, and I haven't got grey hairs, and there's nothing in the way of wrinkles on my forehead. It has been suggested that the youthful look is to do with having lots of friends and a non-traumatic life, but that can't be the case with me: my life has been very traumatic, what with poverty, and having no friends.
I think prolonged youthfulness might be more to do with the non-development of your personal life. I haven't succeeded in a lot of things and that makes me feel young. I'm still eager to achieve and am founding a new political party, the Real Democracy Party, introducing random selection systems for candidates. But I haven't ever earned any money, which is very demoralising.
Looks are only one part of ageing. If you're too established in your attitudes, your mind will be more aged. I don't drink and I don't smoke. I don't drink coffee. My health is better than it has ever been, because until recently I'd suffered from chronic fatigue syndrome. So I have been much less active than most people, which might have made a difference. People who lead a high-speed life age more quickly. I think there's too much obsession with speed.
I'm not a great mixer, but the people I know are in their late twenties or thirties. I'm a bit childish in my manner - clever, in a way, but also an ignorant twit, and that might make me seem younger than I am. The thing is, you never know how people are making these judgments, and it might just be that they are being polite. After all, nobody ever gets told that they look their age.
AUDREY LEATHARD, 63
Professor in interprofessional studies, Surrey
Dr Weeks identified various factors in extended youthfulness and many of them apply to me. People are more likely to be childless or have small families: I have just one daughter. Dr Weeks's subjects were likely to be extremely vigorous and athletic: I have loved sports since school. I'm passionate about water-skiing, I play tennis three times a week, go ice-dancing twice a week, and ride all winter.
It is immensely important to have good posture. My headmistress at school was ferocious about this and am I grateful. Regular holidays are key. We have a terrible climate and it's necessary to have warmth and sun. Dr Weeks says that the superyoung are more likely than the rest of the population to tell the truth. Now that's something I feel very strongly about. Also, my doctor friends tell me that 20 per cent of the population suffer from clinical depression. I'm emphatic about this: depression doesn't help one in life. One should brush oneself down and go on. My husband sometimes tells me that people would never know my age. It's in the presentation - I make sure I'm snappy. I don't want to bore my students. I don't think about getting old. That's all in the mind. But I don't go out and do crazy things I can't recover from.
I'm in that small group of people who have a very happy marriage. It helps not to have any of that ghastliness of divorce. I could have married all sorts of people but it's about making a sensible decision based on like interests. My husband likes sport, although not as much as I do. He doesn't look particularly young - he's lost all his hair. That's one of the problems for men, unless they happen to be Robert Redford. My priorities in life are having everything in its place, and maintaining a balance between looking and feeling good. And there are always opportunities for sport.
STEPHEN BENNETT, 53
About 10 years ago, people just stopped believing my age. I had always looked young but I guess that the discrepancy between my actual age and my appearance had become more marked. I'm a musician and there's a lot of ageism in the profession: in some countries they don't hire you to play in orchestras if you're over 35. But I can get away with it by never telling them how old I am.
I'm quite philosophical about growing older, although what I do find sad is the idea of missing your former health and vitality. Still, I eat what I want, don't smoke, and drink a glass of wine every day or so. I keep in touch with my childish side and have friends of all ages - I'm very sociable. I've loved classical music and theatre since I was a kid, so they have always been part of my life. I've never really liked discos because I don't like not being able to have a conversation.
Before, when I used to worry about ageing, it was at the prospect of being single and unable to attract women - of being alone. For a while, I was glad to look so youthful because it meant that I was able to go out with younger girls. I was going out with one woman who was 28 when I was 44, and it was going well, until she found out my age and broke up with me. I found that weird: I've never thought about age in those terms. For a very long time my girlfriends were always in their twenties. I was going out with 25-year-olds at the age of 16, and I still was when I was in my late forties.
I was married for a short time but it didn't work out. She was 21 and I was 45 when we married and it was great at first. But it turned out to be the biggest mistake I ever made, and quite a useful one. Until then I'd always thought I was a good judge of character. Now I'm in a relationship again. She's 37, so there's not such a huge difference in age this time.
THE REVEREND BETSY GRAY-KING, 44
Minister for the United Reformed Church, Oxford
A while ago, I did a fitness test which assessed me as being seven years younger than I really was. Added to this, people have always assumed that I am far younger than I am - at 44, I still can't get out of the situation of being referred to as a girl, which tees me off slightly. Because I look young, there's part of me that wants to be recognised as a grown- up. People have definitely patronised me throughout my life - more so, perhaps, since I became a woman minister 10 years ago. Until then I'd been a professional artist. I still paint. I've just got a new studio and am preparing for an exhibition.
I suppose I do live healthily but I don't do anything for reasons other than just to feel good. I eat wholefood, nothing prepared; I smoke the occasional cigar; I drink. But it's all about attitude, in the sense that I don't worry very much - I'm an eternal optimist. I think that's the key. If it was all to do with sport and fitness I probably wouldn't be here today.
My husband is four years younger than me but the funny thing is that he looks older. He is boyish by nature but has quite a few grey hairs. We both act young, although in fact we're highly responsible individuals. My children are 15 and 17; sometimes when I tell people that I have kids they expect them to be aged about two and four. We have a very good relationship but there's no question that I'm the mother. I don't try and be a teenager with them, although I do follow their music - they're both rock musicians.
Sometimes I do find that my contemporaries seem older than me. Occasionally I meet someone and think that they must be about my age, before discovering that they're 10 years younger. But I don't want to give the impression that looking and feeling young is something I strive for. It's a consequence of other things.
COLIN WALTERS, 64
A few years ago, my wife sent a photograph of me to Dr Weeks. I've still got all my hair and it's the same colour as ever. I'm slim; my skin is clear. People have commented on my youthful looks for years. I think I do stand out among my contemporaries.
Ageing seems to be a lot to do with whether someone is a dullsville or whether they're getting out and doing things. The bottom line is that young-looking people are active. Soon I will be 65, which used to seem like a pipe-and-slippers age, but it doesn't any longer. I do a lot of stretching and exercising and make an effort to go to yoga and play tennis.
I didn't feel very young when I came out of intensive care a few years ago, after having major heart surgery. I had to pick up my life again, but I'm very self-motivated. Having a loving wife is also important. She is a very young 62, and we have a lot of laughs. I've only been married for 15 years, so we don't have children. When my pension comes through, we're going to travel the world.
I'm more aware of diet, health and medical issues now. I do eat less meat, and my habits are moderate: a small amount of alcohol sometimes. Don't think I'm a goody-goody, but we all want to go on living. There's a certain amount of vanity involved as well, I suppose.
The secret of life, though, is between those two ears. It's about being positive. I'm still curious, forever getting into new things. I've been a sculptor, I'm a music fan, I go to art classes. Basically, I dabble a lot. It's always been like that. I left school at 15 and started work as a self-employed carpenter and joiner. I'm a very independent person and don't fit into groups. So I decided to work on my own - you know you can depend on yourself.
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