Intense kiss transfers 80 million bacteria

Intense kiss transfers 80 million bacteria

Intense kiss transfers 80 million bacteria

According to a new study, around 80 million bacteria are transmitted during a long kiss. However, not all of them settle in the partner's mouth. If a couple kisses over nine times a day, their oral flora will closely match.

80 million bacteria in a single kiss Kissing is beautiful, can be healthy and has a lasting effect: in just ten seconds we can exchange around 80 million bacteria with our partner in a single kiss. This is shown by a scientific study from the Netherlands, which was carried out by microbiologists from the Amsterdam Institute for Molecules, Medicine and Systems. The researchers, who recently published their results in the specialist magazine "Microbiome", examined how similar the bacterial community in the mouth of couples is.

Smooch experiments with bacterial cocktail As part of the study, the scientists led by Remco Kort conducted a controlled smooch experiment for which 21 kissable couples, both of the same and mixed sex, gathered. "Half of the subjects had to drink a probiotic drink containing a specific bacterial cocktail before each kiss." Every kiss had to last at least ten seconds. It was found that "the number of bacteria in the saliva of the person who received the kiss increased by leaps and bounds after each kiss."

Men report higher kissing frequency In addition to kissing, the study participants also had to answer questions such as when they last kissed or how often they kissed. The researchers found a small discrepancy in the answers: 74 percent of the men surveyed stated that their kissing frequencies were much higher than their partners. Many of the male participants said they kissed an average of ten times a day, while the partners said only five times. However, the scientists have not further investigated what this means.

Bacterial composition in couples is similar That kissing can strengthen the immune system, reduce stress, and even lower high blood pressure and high cholesterol, has often been found. "There is intimate kissing in 90 percent of all known human cultures - we want to find out to what extent partners share their oral flora as a result," said Kort, according to press releases. The researchers came to the conclusion: "The more often a couple kisses, the more similar is their bacterial composition in saliva." But the similarity of oral bacteria is not only due to the exchange of saliva. Couples often lead a similar lifestyle anyway, their eating habits are often adapted to one another and their personal hygiene measures are usually the same.

Transmission of diseases It was also pointed out that (almost) nobody has to be afraid of bacterial exchange, because the human organism is home to over 100 trillion microorganisms. These organisms are responsible, for example, for digesting food, decomposing food or warding off diseases. The exchange of saliva when kissing can also lead to the transmission of diseases. In this way, among other things, Pfeiffer's glandular fever triggered by the Epstein-Barr virus, hepatitis B, herpes in the mouth and other infectious diseases such as measles can be transmitted. (ad)

Image: Uwe Wagschal /

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