'X' became symbolic for a kiss because in the middle ages when alot of people were illiterate and they used to sign documents with an X and then kiss it for sincerity.
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As a rule, 66 percent of people keep their eyes closed while kissing. The rest take pleasure in watching the emotions run the gamut on the faces of their partners.
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Kissing releases masses of oxytocin, a "love potion" that helps couples bond and feel more attracted to each other.
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In medieval Italy, if a man was caught kissing a woman in public, he had to marry her whether he liked it or not.
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People are more likely to tilt their heads to the right when kissing instead of the left (65 percent of people go to the right!)
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You burn 26 calories in a one minute kiss.
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Men who kiss their wives in the morning live five years longer than those who don't.
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According to the New York Times, a study conducted during the 1980's found that men who kiss their wives before leaving for work live longer, get into fewer car accidents, and have a higher income than married men who don't.
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