Kings Of Leon's hit song 'Sex on Fire' is about sexually transmitted diseases (STDs).

The American rockers have joked their worldwide smash was inspired by one of them getting a nasty illness after sleeping with a girl.

When asked if the track - which includes the lyrics "hot as a fever, rattling bones" - was about great sex, one band member quipped: "Actually it's about STDs, that was the inspiration!"

Meanwhile, the group's frontman Caleb Followhill has signed up to be a judge on hit US cooking show 'Iron Chef'.

The series pits a celebrity cook against the "iron chef" to make a series of dishes based around a key ingredient and judges then give their marks.

Drummer Nathan Followill - who is joined in the band by his frontman brother Caleb Followill, bassist brother Jared Followill and his guitarist cousin Matthew Followill - said: "The show is awesome. Me and Caleb are fans of nice meals and nice wine.

"We let Caleb do it because I'm usually so drunk by the end of a meal that I probably wouldn't make any sense and they'd have to bleep out more than they could use."