What causes Dry Eyes?

Did you know that our eyes are the most exposed part of our bodies? Our eyes have a layer of tears to protect them. This layer helps our eyes to flush away debris, fight infection, reduce friction during blinks, and helps our eyes to see. In fact, the tear film does most of the work in focusing light on our eyes (more than eyeglasses!).


The eyes, the most exposed part of our bodies

However, our tears aren’t made of pure water. There are over two thousand components. When they’re in the right mixture, the tears are stable and work well.

The main layers are:

  1. Oily Layer (closest to the air/environment)- produced by oil glands in our eyelids
  2. Watery-mucous layer (that touches the surface of our eyes)- produced by our lacrimal gland and conjunctiva.

 When there’s an imbalance, it’s like taking the roof of a house away. It exposes the parts underneath. With evaporation, our tears become saltier. Increased friction makes our eyes become redder and inflamed. We may begin to feel symptoms of dry eye , such as dry, itchy, sore, sandy, burning or wateriness.

What are the most common causes of dry eyes?

Environment - our eyes are often exposed to wind, dust, smoke, pollen and other chemicals. Even indoor environments can cause dry eyes, due to low humidity from air conditioning (e.g. in the office or on a plane). If you’re indoors, try to reduce direct airflow on your eyes. If you’re outdoors, you can wear wrap-around sunglasses. These deflect the wind and help maintain moist air around your eyes.

Contact lenses - when you put a contact lens in your eye, your body has to moisten the lens, as well as the eye itself. Contact lenses tend to make the tears less stable (and have a lower quantity of tears). The best type of contact lenses for dry eyes are daily disposable lenses. These lenses are changed every day, so there’s no debris or germ build up. Ask your Optometrist about the types of contacts that are right for you. 

Digital Devices - According to a national survey, over 91% of Australians use a smartphone. Multiple devices help us to stay connected. However, when we stare at a device or computer screen, our eyes tend not to blink properly. In addition, digital devices are a source of blue light , a spectrum that may cause damage to your eyes This may be because we’re trying to concentrate and take everything in. However, our tear film doesn’t replenish enough. This leads to more exposure and dry eye due to digital eye strain (Source: Deloitte 2019 Mobile Consumer Survey).

Book an appointment with an Optometrist or Ophthalmologist with an interest in dry eyes now.

Medications - Have you ever had a side effect with a medication? Even small doses of medications can cause dry eyes. Common medications include anti-histamines, antidepressants, anti-anxiety medications, hormone replacement therapy, acne medications and others. Blood pressure, diuretics and birth control medications are also associated with dry eyes. Talk to your General Practitioner about your current medication. Ask them if they’re happy to work with you and alter them, or switch to a different medication. Don’t stop or reduce your medication prior to chatting with your GP.

General Health - Inflammation in the body can spread to the eyes. For example, diabetes , rheumatoid arthritis , lupus , Sjogren’s syndrome, thyroid problems and Vitamin A deficiency are all associated with dry eyes. Diet can often play a role in improving control and symptoms of dry eye. For example, omega-three (or fish oil) is commonly recommended to help dry eyes. Talk with your GP or Dietician.

Age - Our eyes change over time. This reduces their ability to maintain a healthy tear film. Hormones like androgens tend to decrease over time. Our eyelid skin starts to become looser - this means that we don’t blink as strongly. Oil glands start to degrade, producing less oil. The normal bacteria that lives around our eyelids also changes, becoming less diverse. Like a regular check-up at the dentist, eye tests are important to pick up early eye problems.

Gender - Females are more at risk of dry eyes than males. Regular fluctuations in hormone levels can cause dry eyes. Cosmetics may contain hidden chemicals that can cause toxicity to the eyes. This may lead to dry eyes. It’s important to check the labels for ingredients that can make your eyes unhealthy.

Eye Surgery - Lasik is a common cause of dry eyes. Some people notice that it disappears within a few months. For others, it can cause long standing dryness. The delicate nerves of the cornea can be affected. If you are considering any type of eye surgery, make sure you talk to your Optometrist or Ophthalmologist. They can do a series of tests to minimise dry eyes before and after surgery.

Dry Eyes are often caused by multiple factors. This includes things in- and around- your eyes. And also changes in your body. Identifying these causative factors is important to tailor the best treatments for you. To book an appointment with an Optometrist or Ophthalmologist with an interest in dry eyes, the easiest way is to search and book with MyHealth1st.




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