Why are tears salty?

This is an automatically translated article.

The article was professionally consulted by Specialist Doctor I Nguyen Thi Bich Nhi - Ophthalmologist - General Surgery Department - Vinmec Nha Trang International General Hospital.

1. What is the function of tears?

Eyes are a very important and very sensitive part of the human body, the eyes help us to see everything around us, perceive light and color. The eyes themselves are also very closely protected by complex mechanisms and systems.
One of those defense mechanisms is tears. Every time we blink, a fluid is secreted that creates a thin film on the surface of the eyeball, which lubricates the cornea and conjunctiva and prevents the eye from drying out.
The most important task of tears is to protect the window of the soul from the invasion of bacteria and foreign objects. In addition, tears also have the ability to kill bacteria and detoxify. Besides, tears are also a tool to express human emotions.

2. Types of tears and the difference between them

Basal tears: These are tears that are secreted daily, its composition includes water, lipids, mucin, immunoglobulins, sodium, potassium and antioxidants such as ascorbate and urate. The main function of tears is basically to maintain moisture, protect the eyes from pathogens, foreign bacteria, similar to other body fluids such as sweat, saliva, and urine. Reflective tears: These are tears that are formed in response to a strong external stimulus such as when dirt enters the eye. This type is secreted naturally, not due to human emotions and unintentionally. Emotional tears: These are the final tears, produced as a result of intense emotional changes such as happiness, grief, exhaustion, or bodily pain. .. The difference between the types of tears is mainly in the formation mechanism of each type. While basal tears are produced every day, when we blink, reflex tears are seen as a response to external factors that attack the eyes.
However, emotional tears are the most distinct of the three, the secretion of emotional tears is controlled by the cortical system, which involves the sympathetic nervous system with the release of neurotransmitters. nerve transmitters to activate the lacrimal gland and produce this type of tear.
When viewed under a microscope, you will see the difference between tears produced by emotional changes and tears produced by a pepper spray.

3. Why do tears taste salty?

Why are tears salty? The simple answer is that tears are salty because they contain salt. In our body, there is always a relative amount of salt, about 226 grams.
Research shows that, at any given time, the amount of salt in an adult's body is about one cup. Salt appears in every part of the body such as blood, body fluids, etc. So not only tears are salty, but sweat, saliva or urine also have a salty taste.
According to research, about 98% of tears are formed from pure water, while the remaining 2% are composed of salts and other organic compounds mentioned above.
Despite the relatively low salinity, tears are still an effective tool to protect the eyes from external agents, especially tears are an effective bactericidal tool. Tears are also considered part of the immune system, so salty tears are very important.
Tears are secreted each has its own purpose. Depending on the case, the body will "turn on" the switch to use the right type of tears, helping to take better care of the eyes. Crying is sometimes not a bad thing because tears help protect the window to the soul. Many studies show that emotional tears also contain a large amount of the enkephalin endorphins and natural pain relievers - helping the body regain emotional balance in a better way.

4. When do we shed tears?

Tears of happiness Not only when sad or in pain, when happy people also shed tears. When emotions are sublimated, tears flow as an expression of joy, pride or sometimes great honor.
Tears of Sorrow When faced with unhappy things or in moments of despair and fatigue, the nervous system stimulates the tear glands to secrete emotional tears.
Objective reasons Sometimes in simple everyday situations such as when cutting onions, tears also flow.
If you are experiencing vision problems, go to a medical facility immediately to be examined and treated by doctors as soon as possible. Currently, Vinmec International General Hospital has vision-related service packages such as:
Refractive error screening package Cataract surgery consultation and examination package Ortho-K package BS CKI Nguyen Thi Bich Nhi has nearly 10 years of experience in the field of ophthalmology. Treatment of medical eye diseases as well as eye surgery such as: pterygium, entropion, milia, glaucoma and cataract surgery by Phaco method. Besides, it also treats diabetic retinopathy by intraocular Anti-VEGF injection and ophthalmic surgery. Currently, the doctor is an Eye Doctor in the Department of Medical Examination - Internal Medicine, Vinmec Nha Trang International General Hospital.
For more information, you can contact Vinmec Health System nationwide, or register online HERE.