Unauthorized Biography Reveals ‘Intimate Life’ Of Simon Cowell

He gets colonic irrigations, Botox injections and vitamin drips, and insists on black toilet paper in his home.

A revealing new biography offers intimate — some might say too intimate — details about Simon Cowell, along with a portrait of the entertainment mogul’s savvy business side.

“Sweet Revenge: The Intimate Life of Simon Cowell” is written by British journalist and biographer Tom Bower, whose previous subjects include former British Prime Minister Gordon Brown, jailed media mogul Conrad Black and ex-Harrods owner Mohammad al-Fayed.

His latest portrait of power centers on the tanned and brush-cut Cowell, 52, who has gained fame in both Britain and North America as producer and an acerbic judge on TV talent shows including “The X Factor” and “America’s Got Talent.”

Bower says he became fascinated by the story of a middle-aged music producer who struck gold by turning the old-fashioned talent contest into a slick 21st-century phenomenon — and in the process earned a fortune estimated at 200 million pounds ($320 million) by the Sunday Times Rich List.

The book paints a picture of a man who struggled for years in the music business, spurred on to success out of a desire to prove his detractors wrong.

“He had 20 years — more than 20 years — of humiliation,” Bower said. “At school he was a total failure and as a music producer he was a total failure.

“But what he did have was charm and an ability to understand the music business because of all this failure.”

“Sweet Revenge,” published in the U.S. by Ballantine Books on Tuesday, is billed as the first book about Cowell written with the mogul’s participation — though not his authorization. Bower spent many hours with Cowell aboard his private jet, at his Los Angeles home and on his yacht in the south of France and the Caribbean.

But he says Cowell told some friends and associates not to talk to him. Writing the book became “a cat and mouse game” between him and his subject.

“He clearly wanted his story told properly, but there are parts he didn’t want told and it was up to me to find out about them,” Bower said.

Cowell has stressed that the book was not written with his approval, tweeting: “This book is not written by me. It is unauthorized. The writer is Tom Bower.”

Cowell can’t have enjoyed the revelations in The Sun tabloid, which has been serializing the more salacious bits of Bower’s book.

Among the details: Cowell gets regular colonic irrigations because “it’s so cleansing — and it makes my eyes shine brighter.” He is put on a drip of vitamins and nutrients for a half hour each week.

He’s not gay, despite long-standing rumors. The book reveals bedroom secrets including a brief affair with former “X Factor” judge Danii Minogue. But Bower says that Cowell isn’t interested in serious relationships.

“He is only interested in women who are uninhibited and uncomplicated,” Bower said. “He is not interested in relationships. He’s a schoolboy.”

He is, however, generous. Bower says Cowell gave his ex-fiance Mezhgan Hussainy, a makeup artist on “American Idol,” a $5 million Beverly Hills house as a parting gift. Most of his exes have refrained from spilling the beans in the media.

While Britain’s tabloids have focused on Cowell’s sex life, Bower is more interested in the story of money and power, of “business rivalry and the skullduggery.”

At the heart of the book is Cowell’s feud with fellow svengali and former Spice Girls manager Simon Fuller. The pair fell out over the 2001 British musical talent-show, “Pop Idol,” progenitor of “American Idol.” Fuller was listed as creator of the show despite what Cowell said was a verbal agreement to split the credit.

A legal battle between the two men was settled out of court, with Fuller getting the creator credit for “Idol” — though Bower says he found “overwhelming” evidence that Cowell played a vital role.

Bower said Cowell was “naive and humiliated by Fuller’s dexterity.”

“He didn’t understand the importance of owning a format,” Bower said. “He learnt his lesson.”

He said Cowell became “incensed” by the “createdby Simon Fuller” credit on “Pop Idol” and “American Idol,” and vowed to create his own rival show.

The result was singing competition “X Factor,” which had its debut in Britain in 2004 and in the U.S. last fall. Cowell also created “Britain’s Got Talent” and executive produces its U.S. spinoff, “America’s got Talent.”

Cowell’s response to the book, published in Britain on Friday, is so far unknown.

Publicist Max Clifford — who says Cowell pays him hundreds of thousands of dollars a year to keep stories out of the press — said he had advised Cowell not to speak to Bower, because it would undo years of carefully protected privacy.

“He knows it was a mistake,” Clifford said.

“For Simon, who has protected his privacy and never, ever spoken about his relationships with anybody, to suddenly be quoted about this, that and the other is to me very damaging.

“Having created an image that’s been hugely successful, to see him damage it like that is sad and disappointing,” Clifford said.

Bower, though, thinks the book’s portrait of Cowell is fairly positive.

While Bower has been openly hostile to some of his previous subjects — he called Gordon Brown a ruthless bully and Conrad Black a crook — he has a soft spot for Cowell.

“He’s not a crook,” Bower said. “So far he hasn’t sued me. And it was good fun.

“He doesn’t sit on his laurels. That’s what’s endearing about him. Although he is vain, he is a perfectionist and a professional — and he understands the business better than most.”