A lot can happen when two people share a kiss. In addition to revving up the arousal engines, kissing also increases oxytocin levels (the hormone associated with bonding and attachment). Some experts even speculate that for some, kissing is more intimate than actual intercourse.
But before you pucker up, keep this in mind: Smooching for just 10 seconds can transfer as many as 80 million bacteria.
In a recent study out of the Netherlands, researchers questioned 21 couples about their kissing behavior and frequency of intimate kissing. From there, oral swab samples revealed that couples that kissed more frequently shared similar salivary germs.
In other words, the more intimately and often you kiss your partner, the more likely you are to share mouth bacteria.
“Intimate kissing involving full tongue contact and saliva exchange appears to be a courtship behavior unique to humans and is common in over 90 percent of known cultures,” lead author Remco Kort said in a statement.
While the findings may have some people thinking twice before a make-out session, keep in mind that kissing is also linked to a number of health benefits. Boosting self-esteem, burning calories, erasing headaches and reducing blood pressure are all on the list.
So why do we kiss? The truth is that the origins of kissing are a bit muddled. According to a 2013 Psychology Today report, some experts theorize that it helps people better assess a potential new sex partner. This, in turn, may play a biological role in the way in which we choose our mates. Others guess that kissing serves to promote intimacy and reinforce trust.
Either way, it’s typically thought to be a sexually stimulating act for both genders.