Humans produce three distinct types of tears, each with a unique chemical makeup.

The three types of tears are classified as basal, reflex, and psychic (emotional) tears. Basal tears are constantly present to coat the cornea, providing a barrier against dust and bacteria. They contain lysozyme, an enzyme that acts as a natural antimicrobial agent to prevent infections.Reflex tears are triggered by sensory nerves in the cornea in response to irritants like onion vapors, pepper spray, or dust. These tears are released in larger volumes to wash away the offending substances. Studies show that reflex tears are mostly water and lack the specific proteins found in other tear types.Emotional tears are unique to humans and are triggered by the limbic system. Research conducted by Dr. William Frey at the St. Paul-Ramsey Medical Center in the 1980s found that emotional tears contain significantly higher concentrations of protein. They specifically carry stress-related hormones like adrenocorticotropic hormone (ACTH) and leucine-enkephalin, a natural painkiller.This chemical difference suggests that crying serves a biological purpose beyond just expressing sadness. By shedding these hormones through tears, the body may be physically lowering its stress levels. This process helps restore emotional balance and explains why people often feel a sense of relief after a good cry.