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 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 $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.

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.

Queen’s 86th birthday marked by 21-gun salute

LONDON — The Royal Navy has fired a 21-gun salute to mark Queen Elizabeth II’s 86th birthday.

The queen is traditionally given gun salutes on her birthday at military bases around the country. Saturday’s main gun salute was fired at Portsmouth Harbor on the south coast of England.

The queen celebrates her birthday twice, with smaller family celebrations on her actual birthday and a second, grander celebration at London’s Buckingham Palace on her “official” birthday, which falls this year on June 16.

This year, the queen will also celebrate her Diamond Jubilee to mark 60 years on the throne on the weekend of June 2-5.

Usher takes his talents off-Broadway

NEW YORK — Usher is heading off-Broadway.

The Grammy winner will join the cast of “Fuerza Bruta: Look Up,” the acrobatic and unconventional play where the audience stands as performers dance and jump around. A news release says the performers “frolic in a watery world suspended just above the audience.”

Usher will perform at two shows as its lead “Running Man” on April 28 at the Daryl Roth Theatre.

“Fuerza Bruta” means “brute force” in Spanish. The play was developed by Diqui James, the Argentine creator of the long-running “De La Guarda.”

Tickets are on sale for $150 and $200. 

Model working in new medium

British it-girl Lily Cole doesn’t want to be boxed in: The successful model launched an eco-friendly clothing line, has two upcoming films and a new TV series in the works.

“I quite like breaking down this conception of art as this very kind of insular space,” Cole, 23, who recently graduated from Cambridge with a degree in art history, said in a recent interview.

“I’ve worked with a lot of artists through film as a medium … so I’d love to keep doing more within that medium.”