Last week on Mid-Morning Matters, my radio and TV show (there's a webcam), I hosted a phone-in that questioned for the first time Jesus's ability to walk on water. My own theories include "thick layer of ice below surface" and "submerged jetty". Yet many of my callers refused to scrutinise Jesus's deeds at all, preferring to take them at face value, even if that betrayed a lack of intellectual curiosity. I was saddened by that, so when I was asked to sum up why I've become a national treasure, I wanted to look at the facts.

What is a national treasure? When does a man or, to a lesser extent, woman go from being roundly liked (James May) to loved – sewn into the fabric of British life like an ear grafted on to a mouse's back? It's a funny thing, national treasurehood. It's not like other hoods, such as "neighbourhood" or "Robin Hood" or "extractor fan hood". It's a concept that's hard to define and even harder to grasp.

Yet it's the Holy Grail (a kind of Middle Eastern cup) for those in the public eye. Kay Burley has a ringbinder on the subject, a dossier of newspaper cuttings she uses to work out why Clare Balding, say, is adored, whereas she has to spend her summer holidays writing to universities to ask for honorary degrees.

In the male TV presenter category, the field is more crowded but I think it's fair to say I'm there or thereabouts. For whatever reason, Eamonn Holmes and myself have broken away from the peloton of over-50s male broadcasters. Alastair Stewart, John Stapleton and Nick Owen huff and puff without gaining ground, while Schofield and Madeley have had to stop by a safety car to be sick (still metaphor). Eamonn and I seem to have gone from strength to strength. Watching him in a bar, working the room, helping himself to crisps and nuts, it's easy to see why he insists the make-up girls at Sky call him Mr Brilliant.

I like to think I share that standing. "How can you? You're not even on the telly," he jokes, before laughing while making a "dzaaah" sound with his mouth which would make some people want to thump him in his stupid throat, but which I find genuinely endearing. He's forgetting that I've done all that. In the 90s, I broadcast to nationwide audiences thanks to two series of my TV chat show Knowing Me, Knowing You (only one was broadcast, the other mapped out on a flipchart). More recently, on local radio, I've sought to refine my audience to a smaller group – sometimes as low as 200 in half-term holidays. But it means I'm making an ever-more personal connection with the public.

So why me? Why am I clutched to the nation's breasts? It's because I'm normal. I'm one of you. I do what you guys do. Get up on a Saturday, make a batch of granola, put some toast on before doing a dozen lunges in front of Saturday Kitchen. (Note to the producers: drop the Omelette Challenge. Just admit it's not working. It reveals next to nothing about the respective culinary skills of the competitors and the raw product served up sets back public confidence in eggs two decades or more. Grow up.)

And that normality, that common touch, that easy way of using slang expressions instead of big words when addressing workmen, has elevated me to national treasurehood. And for that, I thank each and every one of you. Thank you. Each and every one of you.