“Pornography may have many beneficial effects for some people in their sexual lives, and many don’t see themselves as harmed in any way,” Malamuth said.

In one study published this month in the International Journal of Intercultural Relations, University of Hawaii at Manoa researchers compared poses of women in photographs taken from popular pornography websites, magazines and porn-star portfolios, in Norway, the United States and Japan. These three countries were chosen because they fall in different portions of the United Nations’ Gender Empowerment Measure, a measure of women’s political and economic power in a nation. Norway is No.1 globally on the scale, the U.S. is No. 15, and Japan is No. 54.

The researchers compared “empowering” and “disempowering” poses in the popular pictorial pornography of each nation. An example of a disempowering photograph would be a woman tied up or contorted, with little care given to her own comfort. An empowering photograph would be the opposite, for example an unbound woman facing the camera with confidence.