Approximately 141 million Valentine's Day cards are exchanged worldwide every year.
104
Holding hands with someone you love can alleviate physical pain as well as stress and fear.
26
Couples' personalities converge over time to make partners more and more similar.
235
In medieval Italy, if a man was caught kissing a woman in public, he had to marry her whether he liked it or not.
456
The typical person spends about 600 hours having sex between the ages of 20 and 70.
234
Wearing red increases attraction.
30
The single biggest predictor of love is proximity.
30