Fiona McCade: There are times when reality is good thing THERE are around 24 million adult men in the UK, but did you know that 3.6 million of them are astronauts? Are you aware that at least 2.4 million others are professional footballers? Well, in their dreams, but also in reality if you believe damned lies and statistics. According to a new survey, about 15 per cent of us grow up to fulfil our childhood career hopes. That's an awful lot of train drivers and rock stars, so I think some of the respondents to the survey might have been embellishing their CVs a tad. If that figure of 15 per cent is to be believed, loads of people must have dreamed of claiming Jobseeker's Allowance when they were kids. About as unlikely as nearly two million having the burning desire to be accountants. I don't think we're dealing with the truth so much as people's pride here. Ambition and its fulfilment seem to be things that people often lie about. It's as though we find it hard to admit to ourselves that our lives haven't quite gone to plan. Currently, there's a very fashionable lie, which I hear constantly, that says: "You can be whatever you want to be." It's a mantra spouted by all sorts of gurus, life coaches and spiritual types, but if it were true, Britain would have millions of supermodels and what good would that do anybody? Let's say it now, loud and clear: not everyone can be whatever they want to be. Maybe some of us can, but not all of us, by a long way. There's no shame in it. For example, I've always wanted to rule the world. I think I'd be excellent at it, really, I would. I have big plans, but it's obviously not going to happen, is it? Also, when I was five, I quite fancied being a grocery delivery boy from the 19th century, riding on one of those bikes with a box of vegetables on the front. However, I was female and born 100 years too late, so despite my best efforts at time travel and gender re-selection, I had to accept that the project was doomed. Maybe it's because many of my childhood ambitions have been thwarted that I'm so sceptical about the value of achieving long-held dreams, but I also genuinely believe that the things we want when we're very young aren't necessarily what are best for us when we're older. It may sound terribly impressive to say: "Oh yes, I achieved my childhood ambition," but is it really? Isn't that tantamount to admitting: "Oh yes, I haven't changed since I was five"? As we grow and mature, we go through different phases and the most important thing in life is to go after what we need, not just what we think we want. Every series of the X Factor proves that you can't necessarily be whatever you want to be - often, not even the winner manages it - yet every year, another crop of desperate young people half-destroy themselves by buying into the lie. But perhaps there's another reason why 15 per cent of the population think they've achieved their youthful aspirations - they've convinced themselves that they've always wanted to do what they're doing. Of course, if you're in that office, mending that photocopier for the nth time, maybe the only way to stay sane is to tell yourself: "Yes! I AM living the dream! This would also explain all those astronauts. They started off aiming for Cape Canaveral; then realised they were British, so that wasn't going to happen; and ended up on a Ryanair check-in desk. It's almost the same thing. The healthiest approach to ambition is to follow your dream, but be prepared to change it, if and when it stops suiting you. Put your happiness before the blind pursuit of your goals. You might have wanted to be a wizard since you were ten, but unless you've been to Hogwarts, you actually have more chance of becoming an astronaut. It's easier than aiming to be a champion Quidditch player, anyway. It's like being a Lib Dem and still wanting to be prime minister. Sorry, but sometimes, you just have to get real.