by Tom Lutz
Tom Lutz has managed to stuff hundreds of factoids about crying into Crying: The Natural and Cultural History of Tears — everything from a hilarious explanation, circa 1579, of the brain being the source of tears (“when the brain is compressed it ejects great quantities of tears”), to a paragraph on the topic of Bill Clinton’s crocodile tears. In fact, brain compression is precisely the effect of reading Crying, though Lutz’s factoids, contrary to the 1579 theory, don’t cause the reader to manifest Squirt-Gun Eyes. One does, however, feel glimmers of an illumination about the mysterious topic of shedding tears that never comes to pass.
Tears are continually produced in small quantities by the Tear Glands, which are located on the outer side of each eye, slightly above the eye and underneath the eyelid. Tears, which are spread evenly over the front surface of the eye during blinking, clean and lubricate the eye. An important component of tears is lysozyme, a chemical that inhibits bacterial growth on the eye’s surface. Some of the tears evaporate, but the remainder are drained into the nose through the Tear Duct, keeping the nose moist. Lysozyme from the tears prevents bacterial growth in the nose as well.
Another interesting discovery about the content of tears was made by Dr. William H. Frey II, a biochemist at the St. Paul-Ramsey Medical Center in Minnesota. He and his team analyzed two types of tears: the emotional ones (crying when emotionally upset and stressed) and the ones arising from irritants (such as crying from onions). They found that emotional tears contained more of the protein-based hormones, prolactin, adrenocorticotropic hormone, and leucine enkephalin (natural painkiller), all of which are produced by our body when under stress. It seems as if the body is getting rid of these chemicals through tears. That explains why we usually feel better after a good cry. So, there you go. Cry as much as you want – it is probably good for you. But no cheating by inducing crying with onions. Your tear glands know the difference.