Emotional tears are also a different blend from those used for run-of-the mill eye wetting or for reflex crying. The emotional, sniffling variety contain hormones like adrenocorticotropic hormone (ACTH) and prolactin. ACTH is a stress hormone, and prolactin is most commonly associated with the ability of female mammals to produce milk, though it has a wide range of functions in both sexes. No one knows exactly what those hormones are doing in tears, but don’t worry, the blink scientists are working on it.
