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Surprisingly, little research has been done on the health effects of crying. In popular media, crying is promoted as healthful and cathartic. But is it? The results are mixed. In a literature review titled “Adult Crying” published in the Review of General Psychology, Vingerhotes and co-authors bring up some interesting points on what we do know about crying.
When people are asked to recount how they felt after crying (retrospective study), most people state that they felt better after crying. However, in laboratory (prospective) studies, people often feel worse after crying. This immediate effect on affect may be because crying results in sympathetic (fight or flight) overstimulation. In other words, the physical act of crying doesn’t result in relief; however, people feel better after having cried.
From a physical perspective, there is little support for the notion that crying promotes recovery or homeostasis. First, crying either has no effect on or increases heart rate. Second, crying doesn’t result in the shedding of toxic metabolic products; instead, crying decreases levels of secretory IgA which is a first-line immunological defense. Third, crying doesn’t affect levels of pituitary hormones (vis-à-vis cortisol). (Interestingly when animals utter stress vocalizations, they may release endogenous opioids that mitigate pain and confer some solace. Similarly, there may be some unknown hormonal effect that crying has on humans.)
The immediate benefits of crying likely lie in the way that crying "softens" the environment. When people cry, others become more comforting and empathetic. Thus by crying, we are able to convey personal needs and desires. In other words, as you can likely attest to, when someone else cries, you likely feel sympathy for them—you are more inclined to comfort and help them.
But why do some people deliberately engage in crying behaviors? For example, why do some people watch sad movies only to cry after the movie is done. People who engage in deliberate crying behaviors possibly do so because the world seems more positive after negative mood induction.
