Prof Lajeunesse interviewed 20 heterosexual male university students who consumed pornography, and found on average, they first watched pornography when they were 10 years old.

Around 90 per cent of consumption was on the internet, while 10 per cent of material came from video stores.

Single men watched pornography for an average of 40 minutes, three times a week, while those in relationships watched it 1.7 times a week for around 20 minutes.

The study found that men watched pornography that matched their own image of sexuality, and quickly discarded material they found offensive or distasteful.

Prof Lajeunesse said pornography did not have a negative effect on men’s sexuality.

“Not one subject had a pathological sexuality,” he said. “In fact, all of their sexual practices were quite conventional.

“Pornography hasn’t changed their perception of women or their relationship, which they all want to be as harmonious and fulfilling as possible,” he added.

via All men watch porn, scientists find – Telegraph.