Erin Hatton and Mary Nell Trautner of the University at Buffalo examined the covers of Rolling Stone magazine from 1967 to 2009 to measure changes in the sexualization of men and women in popular media over time.
"We chose Rolling Stone, because it is a well-established, pop-culture media outlet," Hatton says in a statement.
"It is not explicitly about sex or relationships; foremost it is about music. But it also covers politics, film, television and current events, and so offers a useful window into how women and men are portrayed generally in popular culture."
Using a "scale of sexualization" that gave "points" if the subject's lips were parted or the subject was only partially clad or naked, the study found 11 percent of men and 44 percent of women were sexualized in the 1960s, while in the 2000s, 17 percent of men were sexualized and 83 percent of women were sexualized.
However, among those images that were sexualized, 2 percent of men and 61 percent of women were hypersexualized.
"In the 2000s, there were 10 times more hypersexualized images of women than men, and 11 times more non-sexualized images of men than of women," Hatton says.
"Sexualized portrayals of women have been found to legitimize or exacerbate violence against women and girls, as well as sexual harassment and anti-women attitudes among men and boys," Hatton says.