Boys and girls, I’m going to start with the obvious truth: I plan to write a short article about the science of first kiss just because I wanted you to see the heartbreaking video at the end of this post. So, what happens when you kiss someone else for the firs time? Science tells us that this kind of moment is packed with emotions, and chemical and biological changes occur in the body during the entire kiss. First, the nerve endings found in the lips get more sensitive and they fire signals to the brain’s cortex to release neurotransmitters like dopamine, endorphins and phenylethylamine. These substances are known to relieve pain, to create feelings of euphoria and to influence mood and attention. As a result, both kissing partners will feel a special sensation of happiness and euphoria.
The adrenal glands are also stimulated and they release norepinephrine and epinephrine, thus increasing the heart rate, dilating the pupils and elevating the blood sugar in the system. The blood moves from the stomach to other organs, producing the arousal. While two people have their first kiss, the oxytocin (a eurohypophysial hormone) is released and it induces feelings of connection. But no science explanation is better than the following video where couple of strangers are asked to have their first kiss on camera: