There are many situations or conditions that are associated with tears. Sometimes, it is as a result of emotions, at other times, it could be as a result of health or climatic conditions, while at other times, the cause could even have no precise explanation. Some studies have found that tears enhance mood while other studies suggest that it actually has a negative effect on the mind. A study also found that crying may lead to both worsened and excited moods. In this post, we will examine the various dynamics of tears, types and characteristics and the chemical composition of tears.

Credits: Pixabay

Tears Are an Important Form of Communication

For children, infants especially, crying is an important form of communication. Infants use tears to express their need for comfort, care or attention. Tears however also are an expression of emotion for adults. Tears tend to amplify the facial appearance of sadness, but more importantly, they may also make others more willing to provide one with the support needed at that point in time.

Image Source
Crying or tearing up is a technique used to build and strengthen personal relationships in that the tears serve as a signal to others that one's defenses are down and that he/she is less of a threat and probably helpless. It may also attract the sympathy of others. Interestingly, crying even sometimes play a role in helping one identify his own feelings.

Crying Makes You Feel Better

There are several mixed findings on whether or not crying is good as an emotional state. While some studies have found it to enhance mood, others suggest that it actually has a negative effect on the mind. A research suggests that crying is more likely to make one feel better when there is an emotional-support person (such as a counselor or a close friend) around. Crying is also likely to improve the mood if it helps to come to a realization of your situation or if it is due to a positive event.

Credits: Pixabay

Either one cries alone or does that with one other person around, it tends to be helpful but crying in the midst of unsupportive people can worsen the mood. Crying as a result of an embarrassing situation also worsens the mood.

THE CHEMISTRY

Most times, we just see tear drops as normal water drops or likened to sweat but there is a particular composition of tears. Tears moisturize the eyes, and they wash away dust and other foreign particles or matter. One may however think of them just as salt water, but on a chemical perspective, there is a lot more going on.

Composition of Tear drops

All tears are produced in tear glands, or lacrimal glands, found under the upper eyelids. Tears are necessary for good vision and for moisturizing the eyes. Crying might make the eyes pale and puffy, but the tears do not affect your eyesight.

Composition of Tear Drop [Image Source]

• An outer hydrophobic oily layer: This layer protects tears from evaporating or spilling out onto the cheeks. The oils here are produced by the Meibomian glands.
• A middle aqueous or watery layer: This layer moves vitamins, salt, and other minerals to the cornea. This composition spreads evenly over the eye, promoting osmoregulation and helping to prevent eye infection.
• A mucous layer: This is the inner layer, which coats the cornea and helps the tear to stay on the eye and keeps the tissue moisturized. The mucins in this layer are produced by goblet cells in the conjunctiva. Mucous helps to ensure a smooth distribution of the aqueous layer over the entire eye.

Types of Tears

There are three types of tear, each type having a mixture of water, salts, fats and proteins. These constituents all play important roles in protecting and preserving the condition of our eyes. The three types of tears include the following:

Basal Tears

This is the liquid that is constantly present in the eye to ensure that the cornea is always wet and nourished. Basal tears are those that keep the eye clean, hydrated, and nourished. The salt content of basal tears can be likened to those of blood plasma. They contain Lysozyme, which protect against infection. Production of basal tears diminishes with aging.

Image Source

Reflex Tears

These are produced as a result of an increase in the level of liquid that the eye produces in relation to a sudden external stimulus or change. They are produced in response to irritations from dust, chemicals, harsh weather, bright light, onion vapours, tear gas or any foreign matter. Reflex tears immediately wash out irritants in the eyes and makes them ‘water’.

Image Source

Emotional (Pyschic) Tears

These are tears shed as a result of pain, sorrow, grief, or happiness. They contain the protein-based hormones prolactin, Leu-enkephalin, and adrenocorticotropic hormone. Leu-enkephalin is a natural painkiller. A high level of emotions triggers the parasympathetic branch of the autonomic system, thereby causing the glands near the eyes to produce tears.

Image Source

CONCLUSION

Tears are important to keep your eye healthy and functioning. It helps get rid of stress and also relieves depression. Though many people assume that tears are mainly composed of salty water, they can also contain lysozymes, proteins, and manganese.

All tears contain salts like Sodium Chloride (NaCl) and Potassium Chloride (KCl), water (H20), and varying amounts of proteins and antibodies, but each type of tear has these components in different proportions. They all vary slightly, according to the kind of tear they are.

---

REFERENCES

• Chemistry is Life
• Dr. Mercola's Natural Health Newsletter
• How Stuff Works
• lookafteryoureyes.org
• Science Notes Posts