A collection of many scientific facts about kissing was published in The Guardian.
During a passionate ten-seconds kiss people exchange about 80 million bacteria, say Dutch experts. However, there are more chances to contract an infection through a simple handshake. Scientists could prove the medical benefit of kisses and their positive influence on the human’s body.
On the lips and on the tongue there are a large number of sensitive nerve endings, and therefore even a slight touch could send various signals to the brain. This in turn can cause extremely pleasurable sensations. When kissing numerous processes are launched involving hormones and neurotransmitters – this is what makes a simple kiss so magical.
So a passionate kiss can activate such hormones as dopamine, which is responsible for desire; oxytocin, the “love hormone”, adrenaline and cortisol – “stress” hormones, the regulators of respiration and blood circulation.
Kissing implies a very close contact with your partner when you could feel the smell of him or her. It is a common fact that the smell of other people has certain information about their DNA. According to the American psychologists, 59% of men and 66% of women admitted that they had ended the relationship due to the fact that they did not like kisses. This confirms that kissing is a great indicator of the genetic compatibility with a potential partner.