NEW YORK (Reuters) - Jim McBride has made it his life's work to know how much naked female flesh appears in movies -- an obsession apparently shared by millions of people.

So far McBride, a.k.a. Mr. Skin, and a staff that includes his mother, who works as a "skintern," have chronicled nude women in more than 25,000 movies and television shows.

It is all recorded on his Web site, www.mrskin.com, which has been running for eight years, and on Saturday McBride launched into print, publishing "Mr. Skin's Skintastic Video Guide" to "the 501 greatest movies for sex and nudity on DVD."

"It's the greatest job in the world," said McBride. "As a kid I used to tape as many movies as I could with nudity and then I'd save the nude scenes on separate tapes. I really amazed my friends with my nudity knowledge growing up."

Some experts say the Internet and more explicit television are fostering a more relaxed response by Americans to bare flesh, even if many people profess to be conservative.

Last week's opening episode of the HBO drama "Tell Me You Love Me," contained at least half-a-dozen sex acts featuring both women and men in the nude, an unprecedented level of sexual frankness for a U.S. cable television show.

But those looking for naked men on McBride's site will be disappointed.

"We have eight to 10 people who just go through movies and television shows ... for nudity, female nudity only," he said. "We don't do male nudity. I think it's mainly because this job is so fun I didn't want to make it work."

He said his Web site, which had a 35 percent boost to nearly 7 million hits a month after it featured in this year's hit movie "Knocked Up", was a celebration of female nudity that only chronicles mainstream movies, not pornography.

"There's plenty of porn sites on the Internet. I never wanted to compete with them. We're celebrating nudity in mainstream film," McBride said.

"The most prolific U.S. mainstream actress is Angelina Jolie," he said. "For an A-list actress, it's pretty incredible to be naked in 10 movies and still be in your early 30s."

The "Skintastic Video Guide" records how much female nudity there appears in a movie and names the nude stars and what body parts they showed. McBride has dedicated the book to his wife and thanks her for "never being naked in a movie."