It has been revealed that Simon Cowell suffered a collapse this summer after the stress of both his professional and personal life became too much for him to handle.
The Sun revealed details of the breakdown from extracts of an updated version of Tom Bower's bestselling book 'The intimate life of Simon Cowell'.
According to this new chapter of the book, which previously revealed Simon's affair with Dannii Minogue, the X Factor judge had become 'paralysed by tiredness and his immune system had collapsed'.
When Louis Walsh was drafted in to cover Simon on the US X Factor last June, it was reported that Simon had come down with the flu.
However, according to the book, it was due to a nervous breakdown.
Bower's book claims that Simon had called Louis saying: "I desperately need peace. I'm craving normality. I've got to work out my demons and come out of it."
Louis was then flown in at the cost of £160,000 to allow Simon the rest he needed.
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The stars' doctor had also instructed him to cut out all health supplements and cigarettes as well as taking a break from work.
Simon allegedly told Louis: "I don't want any more tablets or pills. I'm cutting out the lot, including cigarettes."
Taking a three week break to recover from nervous exhaustion, Simon admitted that he wanted to go back to how he was before the pressure of work became too much.
He reportedly said: "I have to get back to where I was years ago. I had to stop reading texts at three in the morning and making calls later and later. I wanted peace."
However, friends of Simon have said that despite the health risks, Simon has now resumed smoking and late-night working.