Kissing Secrets: Why Men Prefer More Saliva (And Other Revelations)

Susan Hughes and colleagues know how to spice up an academic paper.

[Photo by johncarleton]

Susan Hughes and colleagues know how to spice up an academic paper:

“Kissing between sexual and/or romantic partners occurs in over 90 percent of human cultures […]. Even in cultures where kissing is nonexistent or condemned, sex partners may blow in each other’s faces, lick, suck, or rub their partner’s face prior to intercourse.” (Hughes, Harrison & Gallup, 2007, p.612).

Now, strangely, we all want to know more, so let’s explore their study’s results question and answer style…

Would you have sex without kissing?
Yes said around 50% of men, but only around 10% of women – meaning, of course 90% of women would not have sex without kissing.

How important is kissing before, during and after sex?
Kissing seems to reduce in importance from before to during then to after, but overall it’s generally more important for women in this situation.

How important is kissing as a relationship goes on?
For our male participants it became less important as a relationship went on, but for our female participants it became more important.

How wet and how much tongue?
Overall men preferred wetter kisses and more tongue. Still, both sexes preferred more tongue with a long-term partner. The only gender difference was that men preferred more tongue contact with a short-term partner.

Why might men prefer more tongue and saliva?
Evolutionary psychology suggests kissing may provide important information about mate quality. Unfortunately men are, on average, not so gifted in the saliva-tasting department (technically men have ‘reduced chemosensory detection’). Because of this they need more juice before they can decide.

Would you have sex with a bad kisser?
Only maybe baby, but women were only half as likely as men to have sex with a bad kisser.

What makes you want to kiss a person?
Men based their decision more on facial attractiveness while women were focussing on the teeth.

So, can a kiss kill the romance?
Yes, a previous study found that 59% of men and 66% of women have been put off by a potential partner’s kiss.


This study only covered those who ‘only’ or ‘mostly’ kissed the opposite sex. You same sex kissers will have to wait for future work to get the facts.

And as Dr Boynton points out it’s only undergraduate students of roughly the same cultural background. Practices will probably vary considerably across different cultures.

» Discover more about the psychology of relationships.


Hughes, S.M., Harrison, M.A., and Gallup, G.G. Jr. (2007) Sex differences in romantic kissing among college students: An evolutionary perspective. Evolutionary Psychology 2007. 5(3): 612-631

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This site is all about scientific research into how the mind works.

It’s mostly written by psychologist and author, Dr Jeremy Dean.

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Author: Jeremy Dean

Psychologist, Jeremy Dean, PhD is the founder and author of PsyBlog. He holds a doctorate in psychology from University College London and two other advanced degrees in psychology. He has been writing about scientific research on PsyBlog since 2004. He is also the author of the book "Making Habits, Breaking Habits" (Da Capo, 2013) and several ebooks.