A study has found men are always likely to cheat despite loving their partners and never wishing to leave them and suggests that society embrace more "sexually open relationships".

According to sociologist Eric Anderson, cheating gives the men the best of both worlds. And most of them who do still want to stay with their partner -- they just want to have more sex on the side, the Daily Mail reported.

Monogamy has ostracised men from doing what they most want to do, says the American sociologist, who teaches at Britain's University of Winchester.