I always tell my clients about this study regarding rears. Crying is good for you as it has a purpose. The secret lies in the chemical composition of tears.
Tears are 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, which is 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 also prevents bacterial growth in the nose as well.
The 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 verses the ones arising from irritants (like crying when cutting 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. The body is getting rid of these chemicals through tears. This helps to explain why we usually feel better after a good cry.