Just want to say you can't argue with that!
The local paper did an article for Valentine's Day: A kiss isn't just a kiss
and says the following about endorphins
These neurotransmitters are released when a stressful or painful situation arises. There are three major types of endorphins, but beta endorphins, found primarily in the hypothalmus, give the most euphoric effect to the brain and are the most effective. Besides behaving as a pain regulator, endorphins are thought to be connected to physiological processes including euphoric feelings, appetite modulation and the release of sex hormones.
The article begins, What's first, brain or mouth?