Engaging in a kiss with a romantic companion serves as a profound method for sharing an intimate connection, not to mention a significant volume of saliva and myriad oral microorganisms.
While the notion of exchanging bodily fluids might not be the most enticing prospect for enhancing this year’s Valentine’s Day celebrations, microbiologist Remco Kort, associated with VU Amsterdam in the Netherlands, has found himself captivated by the phenomenon of kissing. He appears to be more intrigued than repulsed.
His conviction is that the transmission of our saliva and its constituent elements might play a more crucial role in the development of romantic attachment than previously understood. To this end, he has articulated a comprehensive set of inquiries in a recent scholarly publication.
What are the physiological ramifications when individuals ingest the microbes of their partners through affectionate contact? Could these microorganisms influence our digestive systems? Our hormonal balance? Our neurological functions? Might the exchange of saliva indeed shape our very perception of love?
Kort posits that such an influence is a distinct possibility. In his “discussion driven by hypotheses,” he characterizes human saliva as a conduit that both “influences and reflects intimacy,” thereby initiating a virtuous cycle. This cycle suggests that escalating affection and emotional connection lead to enhanced well-being, which, in turn, fosters greater love and emotional closeness.
“In contrast to other forms of physical engagement, profound kissing entails the intermingling of saliva and direct lingual contact, effectively inoculating partners with each other’s oral flora,” Kort observes.
Much like a form of oral vaccination, this inoculation of microbial agents could potentially confer unexpected health advantages.
Following the gastrointestinal tract, the oral cavity represents the body’s second most varied microbial ecosystem. Recent scientific findings indicate that the composition of oral microbiota exerts far-reaching influences on systemic inflammation and can affect distant organs such as the brain and the cardiovascular system.
Furthermore, emerging scientific evidence, including earlier experimental work by Kort, demonstrates that romantic kissing between partners results in the exchange of millions of oral microorganisms. Over successive encounters, this leads to a convergence in the microbial profiles of their oral cavities.
“Consequently, this enhanced microbial congruence, coupled with associated sensory stimuli—such as taste, scent, and emotional resonance—may intensify the desire for sustained intimacy, thereby perpetuating the cycle of kissing and microbial transmission,” hypothesizes Kort.
Beyond a multitude of microorganisms, saliva also contains crucial hormones like cortisol and adrenaline, which possess the capacity to influence the recipient. The oral environment even harbors bacteria capable of detecting and responding to key neurotransmitters such as oxytocin, dopamine, and endorphins, all of which experience a surge in the body during intimate kissing.
Historically, certain evolutionary biologists have theorized that passionate kissing offers an evolutionary advantage by facilitating the sharing of vital immunological information via oral microbes. This exchange, according to Kort, might enable partners to develop heightened resistance to each other’s common pathogens, as well as to novel infectious agents they may not have previously encountered.
While such microbial transference can yield beneficial outcomes, it also carries the potential for disease transmission, which likely accounts for the common practice of reserving open-mouthed kissing for individuals with whom one shares a deep level of trust.
At present, these propositions remain speculative, although Kort has put forth a research design intended to validate some of these hypotheses.
Prospective participants in such studies should be mindful: they may uncover more profound insights about their own saliva and their partner than they might have anticipated.
