PROVO — Lyrics that push sexualization have skyrocketed, particularly in the last 20 years, according to a BYU analysis of Billboard Top 100 hits stretching back a half century. And for those concerned with adolescent sexual health and behavior, that could mean stormy days ahead.

The researchers said they'd expected to find a steady increase in sexualized lyrics when they examined songs from the last year of each decade. Instead, according to Cougar Hall, lead author and associate professor of health sciences at Brigham Young University. Starting in 1999, it "skyrocketed."

"We were not surprised that there was an overall increase from 1959 to 2009," said co-author Joshua H. West, assistant professor of health sciences, "but we suspected that the increase would have been more gradual over the decades and not just from 1999 to 2009.

The study, co-written by Shane Hill, an undergraduate when he suggested the topic, is published this week online in a Springer's journal, Sexuality & Culture.

A statement from Springer's says it should "provide food for thought for educators whose focus is to promote healthy sexual development."

The researchers did not try to establish a connection between content and sexualized behavior, Hall told the Deseret News. Other studies have done that. But using the American Psychological Association's definition of sexualization, they coded each year's most popular songs to determine the trend. The increase they found was "disheartening," Hall said, because so many gains have been made in reducing teen pregnancy and combating sexually transmitted diseases and other issues that could be jeopardized.

The APA definition of sexualization includes seeing someone as having only sexual value and inappropriately imposing sexuality on someone, such as a child. They expanded their definition to include songs where a person is depicted as having a large sexual appetite, too. It wasn't just about sex; if the song lyrics indicated a healthy, equitable sexual exchange it wasn't coded. "We want people to have great relationships," Hall said.

"Considering previous research establishing an association between sexualized lyrics and adolescent sexual behavior, our findings unfortunately offer sexuality educators a stormy forecast."

A statement released with the study said that the amount of music listened to by those ages 8 to 18 has increased 45 percent in recent years. "Previous research has indicated a strong link between exposure to sexual media (on screen and in music) and sexual activity. Teens tend to overestimate the sexual activity of their peers and one source of this misperception is the entertainment media."

They did not count all sexual references, Hall said, but rather those that were degrading and sexualized.

And they found "an enormous difference between (lyrics from) Ray Charles or Elvis and what we saw with Lady Gaga and Britney Spears."

The researchers did not, however, attempt to "grade" the lyrics in terms of degree of sexualization. It met the definitions or it didn't.

Because both Hall and West work in health sciences and have seen health disparities based on race and ethnicity, they also looked at the race and ethnicity of the artists and found that artists of color had three times as many sexualized references, Hall said.

He fears the evolution of a new cultural norm. And besides males seeing females as sexual objects, some females sexualize themselves, he says.

That's what led to the study. BYU researchers were analyzing women's profile pictures on MySpace and it was "alarming how many self-objectify," showing sexual body parts, Hall said.

The American Psychological Association, Diane E. Levin, co-authors of "So Sexy So Soon: The New Sexualized Childhood," and other experts all warn that when girls believe their worth is based on their sex appeal, they are more prone to poor body image, the suffer depression, experience eating disorders and abuse substances.

The BYU researchers wrote that "popular music can teach young men to be sexually aggressive and treat women as objects while often teaching young women that their value to society is to provide sexual pleasure for others. It is essential for society that sex education providers are aware of these issues and their impact on adolescent sexual behavior."

"I believe in promoting sexual health and equitable relationships," Hall said. "I'm very concerned that the forecast for that doesn't look good. (Youths) are consuming more music and few have parental constraint when it comes to music. But they learn from music how to treat women and look at one another. Females are seeing themselves as sexual objects. 'This is what I have contributed to the world'."

That, he noted, is unlikely to end well.

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