
Kissing for ten seconds is long enough to transfer about 80 million bacteria between two mouths, according to a study of 21 couples published online today in the journal Microbiome. The researchers also found that couples are more likely to have similar oral bacterial colonies than strangers, no doubt because of all the spit-swapping. As gross as this sounds, exposure to a wider range of bacteria could increase your body’s ability to resist infections, thereby keeping you healthy, as Time points out. Interesting, if not the sexiest thing to think about when puckering up.