However, it is perfectly normal to have friendships with the opposite sex and most people would swear that they are platonic.
Researchers from University of Wisconsin-Eau Claire also found that in a test group of 400 adults, if there were feelings of attraction expressed from only one member of the friendship, it was most often from the man.
Associate professor of psychology and lead author of the study, April Bleske-Rechek believes that because platonic inter-sex relationships are a relatively new concept in the history of human evolution, men are still controlled by their mating instincts.
The participants in the study, which was split into two parts, ranged in age between 18-52.
The first experiment split 88 pairs of friends up into different rooms and without asking anyone to identify themselves proposed a series of questions.
This exercise aimed to glean information about the individuals’ attraction to their companions, desire to go on a romantic date and perception of whether their friends were interested in them romantically.
The results of the study showed that men more frequently admitted attraction to their female friends while also overestimating their friend’s romantic feelings towards them.
Women on the other hand were less likely to fancy their friends or assume that the males had those kinds of feelings for them.
“Historically, men faced the risk of being shut out, genetically, if they didn’t take advantage of various reproductive opportunities. So the argument is that men have evolved to be far more sexually opportunistic,” the Daily Mail quoted Bleske-Rechek as saying.
The following study looked at how friends valued their platonic relationships even if they suspected that there was a certain degree of attraction involved.
The two test groups were “emerging” adults of 18 years of age to 23 and “young and middle-aged adults” aged between 27 and 52.
Across both demographics, the verdict was unanimous; that the benefits of this type of ‘When Harry Met Sally’ friendship outweighed the costs even if it meant their amorous relationships were affected.
Attraction in whatever shape or form was, perhaps unsurprisingly, named as an interference when it came to other relationships, five times more often than it was hailed as a benefit, and the more attracted someone was to a friend, the lower their satisfaction with their romantic partner.
“Sexual attraction came up so frequently as a cost - and these were spontaneous nominations. But people seem willing to take the bad with the good because they find fulfillment in these friendships,” Bleske-Rechek added.
The study has been published in the Journal of Social and Personal Relationships.