How do tears come out

How good are your tearsHowl but!

We shed tears on various occasions to let out our joy, sadness or anger. When else do we get wet eyes and what else tears can do - emergency physician Johannes Wimmer explains everything you should know about this phenomenon.

The pet dies, a child is born, the favorite Bundesliga club is relegated or promoted - anything can make our eyes wet. Sometimes we manage to hold back the tears, sometimes it makes it easier for us to just let them out or we furtively wipe them out of the corner of our eyes.

"There is a big difference between men and women: it has been scientifically proven that women cry more often."
Johannes Wimmer, emergency physician

Tears arise in our lacrimal glands, which, like the salivary glands, are responsible for producing fluids in our body. The tear glands are located on the outside of the eye - between the eye and the skull, explains emergency physician Johannes Wimmer.

There are actually crocodile tears

In crocodiles, the structure of the skull and the location of the tear glands and bags under the eyes are comparable to those of humans. When a crocodile opens its mouth too wide, pressure is created that acts on the glands. This literally causes thick crocodile tears to flow.

"The liquid runs off through the tear sac, which is located on the nose. The liquid runs through a fine tear duct into the middle of the nose. That's why you not only cry tears but also snot."
Johannes Wimmer, emergency physician

Our tear fluid has a similar composition to our other body fluids: mainly water, proteins, enzymes, helpers and antibodies against various bacteria. Our bodies produce one to two milliliters of tear fluid a day. If the eye is irritated, it can quickly become 20 to 100 milliliters. More important than the quantity, however, is the quality - the right composition is what counts.

"It's not so much about how much you produce, but about the quality of the tear fluid. Even if someone produces a lot of tear fluid and the quality is poor, the eyes can dry out."
Johannes Wimmer, emergency physician

The composition of the liquid is basically the same for emotional tears: it doesn't matter whether we cry out of anger or joy. If our eyes water because we have an infection, however, the consistency is different. Sensitive tears are thinner than those that the body uses for protection and self-healing.

Highly complex tear fluid that allows us to see clearly

Tear fluid is composed of three layers:

  1. it is slimy at the bottom
  2. in the middle it is watery
  3. at the top it is greasy (ensures that the water does not evaporate so quickly)

For example, if the fat in the tear fluid is not well composed, too much of it will evaporate. This can lead to dry and irritated eyes. If, for example, the proteins are poorly composed, the tear film tears off quickly - even then, the eye dries out faster.

The fluid in the eye is also important if we want to see clearly. Because the tear fluid evens out unevenness in the cornea.

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