Cowell not happy about new biography.

LONDON — 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 Prime Minister Gordon Brown and ex-harrods owner Mohamed Al Fayed.

Bower’s 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 “American Idol,” “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 oldfashioned 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.

“At school he was a total failure, and as a music producer he was a total failure,” Bower said.

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

“Sweet Revenge,” published Tuesday in the United States by Ballantine Books, is billed as the first book about Cowell written with his participation — though not his authorization. Bower spent many hours with Cowell on his private jet, at his L.A. 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.”

“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.

At the heart of the book is Cowell’s feud with 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 was settled out of court, with Fuller getting the creator credit for “Idol.”

But Cowell vowed to create a rival show. The result was singing competition “X Factor,” which had its premiere in Britain in 2004 and in the United States last fall. Cowell also created “Britain’s Got Talent” and executive produces its U.S. spin-off, “America’s Got Talent.”