Why do we cry? Experts explain the purpose of tears.

Your body has millions of parts working together every second of every day. In this series, Dr. Jen Caudle, a board-certified family medicine physician and an associate professor at Rowan-Virtua University School of Osteopathic Medicine, explains how the body works — and all of its quirks.

Anything that moves someone emotionally — hearing a baby say her first word, finishing a feel-good TV series that you wished had never ended, or reading a breakup text — can bring on tears. In fact, according to the American Academy of Ophthalmology, the eyes produce 15 to 30 gallons of tears a year.

Although animals cry, too, humans are probably unique in shedding tears for emotional reasons. But crying is more just than a way of expressing sadness or happiness. There are actually different types of tears. So what are they and why exactly do we cry? Experts explain.

What are the different reasons why we cry?

“We have three types of tears: the basal tear, the emotional tear and the reflex tear,” Dr. Jen Caudle tells Yahoo Life.

According to Caudle, basal tears are the most complex of the bunch and have three different layers. One layer comforts the eye, another supplies nutrients to the outer structure of the eye and the third protects the eyes from drying out.

Dr. Vicente Diaz, an ophthalmologist specializing in ocular immunology and infectious diseases at Yale Medicine, also tells Yahoo Life that basal tears keep the eye surface smooth and healthy, essential for clear vision.

The eyes also produce tears when we get emotional, says Caudle. “Some studies suggest that crying stimulates the body to produce endorphins, also known as the feel-good chemical,” she explains.

Dr. Rachel Rohaidy, a neuropsychiatrist with Miami Neuroscience Institute, part of Baptist Health South Florida, tells Yahoo Life that crying can be “a response to a high emotional state, like sadness or anger or as a response to physical pain.” She says people also cry when they’re overwhelmed with happiness or a sense of accomplishment.

Charlotte Sidebotham, writing in the British Journal of General Practice, distinguishes between crying, an emotional response, and lacrimation, a physiological response. "Emotional tears contain a higher protein content," she writes. "Being more viscous, they stick to the skin, taking longer to roll down the face."

Interestingly, according to Rohaidy, crying is one of our first forms of nonverbal communication — infants cry to inform us there is a need to be filled, such as hunger or a diaper change. She adds that crying is also an outlet that helps release stress hormones and reduce stress levels.

Lastly, reflex tears are like the eyes’ windshield-wiper fluid, Caudle says. The eyes produce them in response to irritation and pain, Diaz explains. They flush out irritants in the eyes and temporarily soothe them.

Can crying be excessive?

Yes, it can be, says Rohaidy. “When we can’t control crying, and it bleeds into our daily lives,” she says, “then we need to consider if there is an underlying issue, such as anger, depression, panic or feeling helpless.”

If you have frequent uncontrolled crying spells along with feelings of sadness, Rohaidy recommends reaching out to a therapist, psychologist or psychiatrist for help.

But that’s not the only reason why someone may experience frequent crying. Diaz explains that people may shed a lot of tears when their eye surface is unhealthy and reflex tears repeatedly stream down. This crying can be bothersome and can make the vision blurry.

Excessive tearing can also happen when there is a blockage in the tear drainage system, notes Diaz. If you’re experiencing excessive tearing and it’s bothersome, she recommends seeing a doctor for a diagnosis and to discuss possible treatment options.

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