Whereas kissing is commonly perceived as a display of affection in romantic relationships, research highlights a far more nuanced explanation regarding the “function” of kissing within relationships.1 Some research suggests that kissing enables individuals to assess the quality of potential partners by putting individuals in close proximity, making it easier to examine features that are associated with mate value, such as breath and skin texture.2 Other research suggests that kissing elevates levels of arousal, which may lead to sexual intercourse.3 A third body of research suggests that kissing can influence feelings of attachment, alleviate stress, and increase relationship satisfaction.4 Given these varied explanations, the question remains: is there a single purpose for kissing or do all these explanations hold truth?
To further examine the role of kissing in relationships, researchers conducted a study with 308 males and 594 females between the ages of 18 and 63.5 These researchers set out to examine the three explanations regarding the function of kissing. Their first hypothesis was that kissing serves the function of mate-assessment, in that those who want higher quality mates should value kissing more. The second hypothesis was that kissing plays a role in influencing the level of attachment felt between partners. Therefore, individuals who seek out and prioritize long-term relationships over short-term relationships would view kissing as more important at more established or long-term stages of a relationship. Finally, the third hypothesis was that kissing plays a primary role in arousal and the initiation of sex, and as such, kissing should be viewed as most important just prior to sex (especially in short-term relationships).
A survey was given to participants which required them to provide demographic information and answers to questions regarding kissing in various scenarios. Participants also filled out the Relationship Assessment Scale, which asks participants to respond to statements regarding the quality of the relationship, such as, “My partner meets my needs.” As part of the survey, participants also completed the Sociosexual Orientation Inventory-Revised (SOI-R), which generally indicates the extent to which people prefer casual, short-term relationships versus long-term relationships (e.g., “With how many different partners have you had sexual intercourse on one and only one occasion?”). Finally, each participant rated their own self-reported level of attractiveness by responding to the following two questions, “How do you think other people would rate you on physical attractiveness?” and “How do you think other people would rate you on sexual attractiveness?”5
Kissing as an Assessment of Mate Value
The researchers found that those high in self-rated attractiveness rated kissing as more important than those low in self-rated attractiveness. In addition, high mate-value participants responded that their attraction to an individual was more likely to change after the initial kiss than did low mate-value participants, suggesting that the kiss serves the purpose of helping them to find the match. This demonstrates that those who are more selective when it comes to choosing mates (high mate-value individuals) were more interested in looking at cues signaling underlying fitness. Based on these results, the researchers concluded that kissing primarily serves the function of mate assessment.
Kissing Influences Attachment
The researchers also found that greater frequency of kissing in the relationship was related to relationship quality, and that having a partner who the participant felt was a “good” kisser was related to overall relationship quality. In addition, greater satisfaction with the amount of kissing and greater satisfaction with the amount of sex in the relationship were related to relationship quality. The researchers also found that those who were interested in long-term relationships felt that kissing was important before, during, and after sex, whereas those who were more focused on the short-term placed importance on kissing mostly before sex. The authors interpreted this as evidence for the attachment hypothesis. Specifically, it appears that kissing is not solely used for the purpose of arousal, but instead can bring and keep couples together over time and lead to a high quality relationship.
Kissing for Arousal and Initiation of Sex
There was very little support for the arousal hypothesis, because only those who wanted short-term relationships valued kissing just prior to sex. Participants interested in long-term relationships felt that kissing was important at other times as well, and as such, kissing goes beyond the creation of arousal.
Overall, the results of this study suggest that kissing serves two main purposes: to assess potential mates and to maintain the bond between them. Therefore a kiss is more than a physical expression of love for a partner; it is a way to pick a mate and stay close to him/her over time. A kiss is not simply just a kiss.
1Wlodarski, R., & Dunbar, R. I. (2014). What’s in a kiss? The effect of romantic kissing on mate desirability. Evolutionary Psychology, 12(1), 178-199.
2Thornhill, R., & Gangestad, S. W. (1999). The scent of symmetry: A human sex pheromone that signals fitness? Evolution and Human Behavior, 20(3), 175-201. doi:10.1016/S1090-5138(99)00005-7
3Byers, E. S., & Heinlein, L. (1989). Predicting initiations and refusals of sexual activities in married and cohabiting heterosexual couples. Journal of Sex Research, 26(2), 210-231. doi:10.1080/00224498909551507
4Floyd, K., Boren, J. P., Hannawa, A. F., Hesse, C., McEwan, B., & Veksler, A. E. (2009). Kissing in marital and cohabiting relationships: Effects on blood lipids, stress, and relationship satisfaction. Western Journal of Communication, 73(2), 113-133. doi:10.1080/105703 10902856071
5Wlodarski, R. & Dunbar, R. I. M. (2013). Examining the possible functions of kissing in romantic relationships. Archives of Sexual Behavior, 42(8), 1415-1423.
Dr. Marisa Cohen
Marisa, along with a colleague at St. Francis College, founded the Self-Awareness and Bonding Lab (SABL) in Fall 2014. Research has focused on the development of relationships throughout the life span, including factors influencing mate choice and peoples’ perceptions of what makes relationships survive and thrive. Her specific focus is on how various relationship configurations impact the satisfaction derived from them.