Demi Lovato has revealed that Simon Cowell blow dries his hair.

The music mogul is often regarded as a vain chap, but the 'DEMI' star told The Sun that he actually blow dries his mane - despite not actually having too much hair on top.

When asked if Cowell is into grooming, the X Factor judge said: "Yeah, he’s always blowdrying his hair."

Referring to her relationship with the Syco boss, Lovato added: "I’ve been able to tell him things that I don’t tell the public — about my personal experiences, my journey and what I’ve been through. He’s been really, really cool about everything. Way deep down there, he’s a good guy."

Lovato meanwhile has resumed her role as a judge on the US X Factor for what will be her second series, with the show currently in its touring audition phase.