Celebrity birthdays: 5 things you didn’t know about Simon Cowell

Discover more about Simon Cowell on his 54th birthday!

There have been big revelations about Simon Cowell in recent months, from his girlfriend Lauren Silverman's pregnancy to Sinitta's abortion. To mark his 54th birthday today, find out more about the music mogul, from his first TV appearance to his allergy woes.

1. Simon was a TV contestant once upon a time

We're used to seeing Simon in control of others' fates on the likes of 'The X Factor' and 'Britain's Got Talent', but back in the day Si was a contestant just like those he now judges.

Oh yes, in 1990 Mr Cowell made his TV debut on game show 'Sale of the Century'. He won, naturally, but missed out on the big prize. What was his haul? Kitchen utensils. Lucky lucky SiCo.

2. Simon is not on good terms with sheep

Simon might bat away contestants' comebacks with aplomb, but there is something that Si can't fight back against; lambs' wool. He revealed to the Daily Mail he is allergic to the material.

How does he deal with this weakness? Cashmere, darling.

And when he finds a jumper that doesn't make him itch, he buys it in five different colours. He applies this to all of his shopping, buying five of the same shoes, jeans etc. That explains how he has a seemingly never-ending supply of those high-waisted trousers, then.

3. Simon turned down a big offer

When you're as high profile as Simon, you're going to get offered endorsement deals. I could just imagine him as the face (or moobs) of low-cut tops. But there was one offer he was not happy about.

Si turned down a big money offer to be the face of Viagra, telling Glamour magazine his response when his agent told him the news was: "that has to be a f***ing insult".

4. Simon has a connection with Robbie Williams

You don't have to go quite the full six degrees of separation route to link Si with Rob. Rob's cousin is married to Si's sister. Does that make Simon and Robbie fourth cousins thrice removed or summat?

Perhaps that explains why the Robster keeps coming back to help out at 'The X Factor' judges' houses.

5. Leona Lewis convinced Simon to change his eating habits

'The X Factor' winner is pretty persuasive, it turns out, as Leona told The Sun that Simon gets involved in all of her environmental and charity concerns that she asks him to support.

Si even went as far as to turn vegetarian for Leona. But it wasn't a full-on conversion, as it was just a one-day-a-week commitment to Paul McCartney's Meat Free Mondays campaign.