Oxytocin, the Love Hormone, Also Keeps People Apart

A hormone that promotes social attraction also helps men keep their distance

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


Oxytocin, the so-called love hormone, activates feelings of trust and attraction between people when it is released in the brain, and it rises in the early stages of romantic love. Yet it is not just a Cupid's arrow that spurs you to fall in love with the nearest person, according to a recent study published in the Journal of Neuroscience. Instead oxytocin's social magic depends on whether or not a person is in a monogamous relationship.

A team of researchers from the University of Bonn in Germany and elsewhere monitored a first encounter between straight male study participants and an attractive woman in a laboratory setting. When given oxytocin via an intranasal spray before the meeting, men who had indicated they were currently in a stable relationship kept a greater physical distance from the woman in the lab compared with single guys given oxytocin and with single and “taken” guys given a placebo. Although they stayed only 10 to 15 centimeters farther away, the extra distance left the woman outside of what most people consider “personal space,” a zone reserved for loved ones. Moreover, it was not because they did not find her attractive: the monogamous men who received oxytocin rated the woman just as good-looking as the other men did.

The results suggest that oxytocin has a role in maintaining relationships after they are sparked and add to growing evidence for differences in how the hormone acts to modulate social interactions—for example, promoting bonds with familiar people but provoking aggression with strangers. “It's not all positive with oxytocin,” says Dirk Scheele, a psychologist involved with the study. “And what you call prosocial or antisocial depends on your perspective.”

It’s Time to Stand Up for Science

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in that two-century history.

I’ve been a Scientific American subscriber since I was 12 years old, and it helped shape the way I look at the world. SciAm always educates and delights me, and inspires a sense of awe for our vast, beautiful universe. I hope it does that for you, too.

If you subscribe to Scientific American, you help ensure that our coverage is centered on meaningful research and discovery; that we have the resources to report on the decisions that threaten labs across the U.S.; and that we support both budding and working scientists at a time when the value of science itself too often goes unrecognized.

In return, you get essential news, captivating podcasts, brilliant infographics, can't-miss newsletters, must-watch videos, challenging games, and the science world's best writing and reporting. You can even gift someone a subscription.

There has never been a more important time for us to stand up and show why science matters. I hope you’ll support us in that mission.

Thank you,

David M. Ewalt, Editor in Chief, Scientific American

Subscribe