More than half of all people who engaged in online sex were married or in a serious relationship, and some people were doing it as much as 10 hours a day, Australian research showed on Thursday.
The typical participant was a well-educated man with an average age of 41 years who preferred to look at sexual images rather than engage in interactive-type chat, the Swinburne University of Technology found.
Of the study's 1,325 subjects, 55 per cent said they were married or considered themselves to be in a serious relationship, said lead researcher Marcus Squirrell.
And 65 per cent of people who had some form of online sexual contact with someone said they went on to meet them in real life, Squirrell said.
Many used sites to explore their sexuality in a safe environment, but some developed serious addictions to online sex, he added.
"These people are putting so much energy into cybersex -- in some cases up to 10 hours per day -- that it is detracting from their relationship with their partner," he told national newswire AAP.
"It can also adversely affect other areas of their lives, such as their education and employment."