Tears

Rachael Smith - Thursday, October 06, 2016
Would you believe that every year we produce over 30 gallons (or 136 litres) of tears? Although you may not realise it, we are actually crying every second of our lives and there are three different types of tears. Tears are made up of a combination of water, sugar, proteins and fats and all play an important role in protecting and preserving our eyes.

Tears are produced in our lacrimal glands, which then flow into the space between our eyeball and our eyelid. Waste fluid is eventually disposed of through the nasal cavity; hence why our nose tends to run when we cry.

The liquid that is constantly present within the eye are known as basal tears, which ensure that your cornea is nourished and lubricated. Your cornea contains no blood vessels and thus depends on its film of tears for its oxygen supply, which it receives from the air when your eyes are open. Basal tears smooth out irregularities and creates an even surface, which gets reformed every single time you blink. They also act as a lubricant between the eyelid and eyeball to prevent irritation.

Reflex tears are the kind of tears that are produced when your eyes ‘water.’ As a result of an external stimulus, such as dust or foreign particles or irritant substances such as onion vapours or pepper spray – reflex tears occur to wash our any irritants that have come into contact with your eyes. Reflex tears are also related to coughing, yawning and vomiting.

Tears caused by strong emotions such as sadness, grief, anger or happiness are often referred to as emotional tears or psychic tears. Tears produced during crying due to pain or discomfort also fit into this category. These tears actually have a different chemical make-up to basal or reflex tears; they generally contain a larger amount of protein. A high level of strong emotions can trigger the parasympathetic branch of our autonomic system – researches suggest that by excreting these hormones when we cry is actually our body’s way of making us feel calmer and less emotional afterwards.

Here are a few interesting facts about tears:
• All vertebrate animals that spend part of their life on land have basal and reflex tears, but humans are thought to be the only animal that cries for emotional reasons. However, there have been reports of elephants shedding tears of grief after a member of their herd passes away.
• On average, men cry between 6-17 times per year, while women average 30-64 per year. Scientists believe this is due to hormonal differences and the fact that women have smaller tear ducts than men. Larger tear ducts result in being able to contain more tears within the eye before they spill out.
• New born babies cry for an average of 1-3 hours per day. A baby that cries for more than 3 hours per day may be experiencing symptoms of colic.
• The phrase “crocodile tears,” is actually a misnomer. Crocodiles “cry” when they eat as shedding tears allows them to rid their bodies of excess salt they take in with their food.

Sore, gritty and even, surprisingly, watery eyes can be a symptom of the tears either being too few or inefficient. This is commonly called dry eye. We stock a range of highly effective dry eye treatments from the Thea Spectrum and Hycosan range on our online shop.

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