Kissing Couples Share Resistance-Boosting Bacteria

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It’s fun to pucker up your lips and smooch with your significant other, but your make-out sessions may have a healthy twist. Mandy Oaklander of Time reported on a recent study that sought to know what kinds of microbes couples transmit when they kiss.

Remco Kort, Professor at the Netherlands Organisation for Applied Scientific Research, asked 21 couples to French kiss for 10 seconds as a part of his study. The participants’ mouths were swabbed before and after they locked-lips. The results from this small batch of volunteers were that the bacteria in the mouths of couples were much more similar than that those of two strangers:

“Apparently, being with somebody for an extended amount of time and having a relationship leads to a similar collection of bacteria on the tongue.”

In order to test this hypothesis, one person was asked to drink probiotic yogurt and then kiss their partner. Researchers found that the new bacteria was transferred to their partner’s mouth. Kort and his team of researchers found that the more often couples kiss, the more bacteria they shared (and that’s a good thing):

“There are a number of studies that show if the diversity in bacteria increases—more different types of species—this is a good thing. If you look at it from this point of view, kissing is very healthy.”

Couples who kiss can build up resistances by exposing themselves to more microorganisms (around 80 million bacteria). Of course, you should know your partner, after all, there are some unsavory things that can be transmitted through kissing.

If you’re looking to get the maximum amount of bacteria from your partner in a short amount of time, Kort recommends the most efficient way to do that is through a French kiss:

“French kissing is a great example of exposure to a gigantic number of bacteria in a short time. As many as 80 million in a period of just 10 seconds. Some establish themselves on your tongue, but a great many don’t.”