The history of mistletoe, and why this plant pops up around each holiday season, has been long lost– mistletoe has been featured in Norse legends and has been believed to bring both luck and fertility. Now we hang mistletoe above our doors at holiday parties with the playful intent of stealing a kiss beneath it.
Alas, the innocence of mistletoe is lost once microbes join the party!
A kiss is not just a kiss!
New research by the Netherlands Organization for Applied Scientific Research has now found that during “intimate” kissing– meaning that in the course of a kiss, saliva is exchanged between the two partners– literally millions of bacteria are exchanged. According to their study, researchers found that 80 million new bacteria were shared within the span of a 10-second kiss!
Your own ecosystem
Before you run screaming for the hills never to be seen or heard from again– there’s something you need to know about microbes. We have billions of them living on and inside us. In fact, scientists estimate that more DNA in our bodies is bacterial than human.
All these microbes have a name: the microbiome. Commensal microbes play important roles in our lives: digestion and immune function, to name just a couple. All of us have our own, unique microbiome… but we can share it– a little.
Sharing more than a cozy moment!
According to estimates, our mouths contain around 700 species of microbiota. When we kiss, we share some of these with our partner. In fact, the study showed that the more a couple kisses, the more similar their salivary microbiota is! This shared moment is transitory, however– native microorganisms quickly retake their territory; except, notably, on the tongue, where long-lasting “colonization” can occur.
More questions abound
Humans are the only known species to engage in kissing as part of their courting behavior– under a mistletoe or otherwise. With this new information, scientists can now speculate on what purpose kissing evolved to serve: are there chemical receptors that choose a mate with a microbiome that we like? Does the exchange of microbes improve immune function?
Whatever the reason, it does give one pause when considering the simple tradition of a holiday mistletoe hanging innocently above the doorframe!
In other news…
Remember to schedule your teeth-cleaning appointment with Dr. Lawrence soon– the holidays are coming up fast! Call us or schedule online. We look forward to seeing you at your favorite McKinney family dentist office!