Physiological reason why we cry

What happens when you cry, exactly? A salty fluid chock full of protein, water , mucus and oil is released from the lacrimal gland in the upper, outer region of your eye.

This fluid, better known as tears , then flows down the surface of your eye and across your face. Of course, not all tears are of the emotional variety. In fact, three types of tears exist, all with different purposes.

Basal tears are omnipresent in our eyes. These constant tears are what keep our eyes from drying out completely. The human body produces an average of 5 to 10 ounces of basal tears each day. They drain through the nasal cavity, which is the reason so many of us develop runny noses after a good sobfest. The second type is reflex tears , which serve to protect the human eye from harsh irritants such as smoke, onions or even a very strong, dusty wind.

To accomplish this feat, the sensory nerves in your cornea communicate this irritation to your brain stem, which in turn sends hormones to the glands in the eyelids. These hormones cause the eyes to produce tears, effectively ridding them of the irritating substance.

The third type of tears is emotional tears. It all starts in the cerebrum where sadness is registered. The endocrine system is then triggered to release hormones to the ocular area, which then causes tears to form. Emotional tears are common among people who see Bambi's mother die or who suffer personal losses. The phrase "having a good cry" suggests that crying can actually make you feel physically and emotionally better, which many people believe. Some scientists agree with this theory, asserting that chemicals build up in the body during times of elevated stress.

These researchers believe that emotional crying is the body's way of ridding itself of these toxins and waste products. In fact, one study collected both reflex tears and emotional tears after peeling an onion and watching a sad movie, respectively. When scientists analyzed the content of the tears, they found each type was very different. Reflex tears are generally found to be about 98 percent water, whereas several chemicals are commonly present in emotional tears [Source: The Daily Journal.

First is a protein called prolactin , which is also known to control breast milk production. Adrenocorticotropic hormones are also common and indicate high stress levels. The other chemical found in emotional tears is leucine-enkephalin , an endorphin that reduces pain and works to improve mood. Of course, many scientists point out that research in this area is very limited and should be further studied before any conclusion can be made. Incidentally, in Japan some people have taken the notion of "a good cry" to the next level.

They hold organized crying clubs where they watch sad movies and television shows and read tear-inducing books. Onions aren't just associated with stinky breath — they actually can cause the person doing the chopping to tear up. According to the Library of Congress, unstable chemicals released into the air during the chopping process cause this phenomenon.

Lachrymatory-factor synthase is the enzyme to blame. When an onion is cut, the enzyme is released from the onion and converts the amino acids in the onion to sulfenic acid. Comparatively, the tears we make when we are chopping onions are less viscous or sticky. But there needs to be more research conducted to further explore the differences between criers and non-criers. Although the science of why we cry is still being researched, emotional crying is a part of our human experience and most likely helps us bond and give each other emotional support.

Contact Us Call Us: Have you ever thought about why humans cry or weep? These natural chemical messengers help relieve emotional distress along with physical pain. In other words, crying is a self-soothing behavior. Crying puts you in a vulnerable position. From an evolutionary perspective, this would put you at a disadvantage in a fight-or-flight situation.

If you see tears as a sign of weakness, as many people do, you might dislike crying because you want to avoid giving an impression of helplessness. In fact, expressing your weaknesses could generate sympathy from others and promote social bonding.

Most people need at least some support and companionship from others, and these bonds become even more important in times of vulnerability.

When you allow others to see your weaknesses, they may respond with kindness, compassion, and other types of emotional support that contribute to meaningful human connection. Experts believe these happy tears may help you process and regulate intense emotions. Witnessing their pain could make you cry, too. It may not even matter whether that person is real or fictional, according to a small study that explored sympathy crying in response to emotional movies.

People who experience abuse , neglect, or other trauma may struggle to make sense of what happened and cope with the resulting emotional pain and turmoil. These tears may not necessarily be forced, though, as feelings of frustration and helplessness can make most people cry.

If you find yourself regularly using tears in lieu of more productive approaches to communication and conflict resolution , a therapist can help you explore potential reasons behind this behavior and find healthier ways to express your needs and feelings.

Not surprisingly, people who live in societies where crying is more accepted may cry more frequently. A prevailing theory in the s held that emotions—especially love—heated the heart, which generated water vapor in order to cool itself down.

The heart vapor would then rise to the head, condense near the eyes and escape as tears. Finally, in , a Danish scientist named Niels Stensen discovered that the lacrimal gland was the proper origin point of tears. In his book, Vingerhoets lists eight competing theories. Some are flat-out ridiculous, like the s view that humans evolved from aquatic apes and tears helped us live in saltwater.

Other theories persist despite lack of proof, like the idea popularized by biochemist William Frey in that crying removes toxic substances from the blood that build up during times of stress. Evidence is mounting in support of some new, more plausible theories. One is that tears trigger social bonding and human connection. While most other animals are born fully formed, humans come into the world vulnerable and physically unequipped to deal with anything on their own.

Even though we get physically and emotionally more capable as we mature, grownups never quite age out of the occasional bout of helplessness.