Want to know what a kiss reveals? A new book, 'Kisstory' tells the history of kissing and reveals that not all smooches are romantic. For instance, in Naples in 1562 kissing publicly was punishable by death. The word "kiss" comes from the Germanic word kussjan, probably because of the sounds it makes.
However the first openly gay big-screen kiss came even earlier - as the 1922 movie Manslaughter included two lesbians snogging. The most kisses seen in a film was 191 - Don Juan, in 1926 - while the longest-ever kiss lasted a breathtaking (and strength-sapping) 31 hours and 30 minutes.
In 1990 Alfred Wolfram kissed 8,001 people in eight hours during a festival in Minnesota - an average of 16 people per minute. But kissers should beware as a single snog can contain up to 278 types of bacteria, some of which may carry diseases, while a passionate peck can raise hormone levels enough to shorten your life by a full minute.
