A few years ago I accidentally caught sight of the back of my head in a mirror. At that moment I knew my time had come. Male pattern baldness was not just knocking on my front door: It had burst in, raided the fridge, and was settling down on my sofa for the long haul. We were going to be buddies whether I liked it or not.

Years later I'm over it (really). What was interesting, I thought as the trauma subsided, is whether this meant I was now officially "grown up". I mean, baldness is what old people have, right? It's like grey suits, musky aftershave and nasal hair. If I'd somehow missed this transition from "young" to "old", or at least "middle aged", I guess I needed to make some other changes too.

So I went to task ... no more young stuff. Ditched the red sports car. Xbox - gone. I even thought very hard about not wearing jeans to work anymore.

Thing is, I didn't really feel old. It was all very confusing. Maybe I wasn't really grown up after all. Maybe my follicular woes were a blip, a freak of nature. "Relax, its fine!" I thought as I (re)unpacked my Xbox and dusted off Halo 3. No-one will ever get to see the bald spot ... as long as I don't stand under any reasonably powerful light source. Or bend down. Ever. 

But now I can run from the truth no longer. According to the latest European Social Survey Britons think, on average, that middle age begins at 35. I am now officially middle aged.

Or am I? Dominic Abrams and Melanie Vauclair, who carried out an extensive analysis of the survey data, found something that may yet save my spring chicken status. Whether people regard us as "young", "middle aged" or "old" is not at all an absolute ... it depends on the age of who you ask.

Abrams and Vauclair found that according to 15-24 year olds youth ends at 28. You're then middle aged until 54, and then you're old. Ok, not so great for us late-thirty-somethings ... but it gets better. People 80 or older think that youth ends at 42 (Hurrah!) and old age starts at 67. It seems that age is, quite literally, in the eye of the beholder.

So it's comforting to know that there's still some old folks out there who'd consider me young. Funny thing is, knowing this actually makes me quite look forward to being middle aged. I can now see all the good things that it brings ... confidence, that feeling of being an established, well-balanced individual. What I never liked was that conveyor belt sensation ... the idea that once you cross over an age boundary there was no going back. But if boundaries are bendy you don't loose anything by transitioning from one to the other, you just have to stretch a little more. And I'm more than happy to do a little bit of extra stretching as I get older.

So I'm off to play on the Xbox, but as I assume my identity as a genetically-enhanced-super-cyborg-soldier of the future, I'll be doing it in a much more confident, established and well-balanced manner than I've ever done before ...