What are the ‍5 Causes of Dry Eye?

Every now and then, we all experience that uncomfortable sensation of dry eyes. It’s that gritty, burning feeling that can be irksome at best and debilitating at worst. Dry eye is more than just an occasional annoyance, it’s a common condition that affects millions of people worldwide. But what exactly is dry eye and why does it occur?

Dry eye, medically known as keratoconjunctivitis sicca, occurs when your eyes do not produce enough tears for adequate lubrication, or when the tears evaporate too quickly. This can lead to inflammation, damage to the eye's surface, and even vision problems if left untreated. The symptoms of dry eye can range from mild to severe and can include stinging or burning sensations, red eyes, blurred vision, and a feeling of having something in your eyes.

Understanding the causes of dry eye is the first step towards effective treatment. While there are a multitude of factors that can contribute to dry eye, this article will focus on the five primary causes: environmental factors, certain medications, underlying medical conditions, long-term contact lens use, and the aging process.

Understanding What Causes Dry Eye

Before delving into the specifics of what causes dry eyes, it's essential to understand the role of tears in eye health. Tears are a complex mixture of water, fatty oils, and mucus. This mixture helps to keep the surface of our eyes smooth, clear, and protected from environmental irritants. When the production or quality of tears is compromised, dry eye can occur.

Dry eyes can be caused by a variety of factors, often a combination of several. These factors can be broadly categorized into the following five causes, each of which will be discussed in detail in the following sections.

The Aging Process

Just like the rest of our bodies, our eyes change as we age. One of the most common causes of dry eye is the natural aging process. As we get older, our bodies produce fewer tears. This is particularly true for postmenopausal women, who are at a higher risk of dry eye due to hormonal changes.

But why does aging affect tear production? The lacrimal glands, which produce tears, can become less efficient as we age, leading to decreased tear production. Additionally, the meibomian glands, which produce the oily part of tears, can become blocked or dysfunctional with age, causing tears to evaporate too quickly.

Environmental Factors

Our environment plays a significant role in eye health. Environmental factors such as wind, dry air, smoke, and dust can cause tears to evaporate more quickly, leading to dry eyes. Even seemingly innocuous activities such as reading, driving, or staring at a computer screen for extended periods can contribute to dry eyes, as these activities can decrease blink rate, thus affecting tear production and evaporation.

Living or working in an environment with air conditioning or central heating can also cause or exacerbate dry eyes. These systems reduce humidity levels, which can lead to increased tear evaporation.

Certain Medications

Certain medications can also cause dry eyes. These can include antihistamines, decongestants, antidepressants, certain blood pressure medications, and birth control pills. These types of drugs can reduce tear production, leading to dry eyes.

The mechanism behind this is often related to how these drugs work. For example, antihistamines - while effective at reducing allergy symptoms - can also reduce moisture in various parts of the body, including the eyes.

Underlying Medical Conditions

Several underlying medical conditions can also contribute to dry eyes. These include autoimmune disorders such as Sjögren's syndrome, rheumatoid arthritis, and lupus. These conditions can directly affect the glands that produce tears, leading to dry eyes.

Furthermore, conditions like diabetes, thyroid disorders, and vitamin A deficiency can also cause dry eyes. Even skin conditions around the eye, such as blepharitis, or eyelid inflammation, can lead to dry eye symptoms.

Long-term Contact Lens Use

Long-term contact lens use is another significant cause of dry eyes. Contact lenses rest directly on the cornea, which can interfere with the natural distribution of tears across the eye. Over time, this can lead to dryness and irritation.

Some types of contact lenses can absorb the eye's moisture, contributing to dry eyes. For this reason, it's important for contact lens wearers to take proper care of their lenses and follow their eye doctor's recommendations regarding wear time.

The Relationship Between Dry Eye and Digital Screen Usage

In our increasingly digital world, screen time has become a significant contributor to dry eye. When we look at screens, we blink less often, which can lead to increased tear evaporation. Additionally, looking at screens often means staring at an object at close range for extended periods, which can strain the eyes and contribute to dryness.

As a result, it's not uncommon for people who spend a lot of time on computers, smartphones, or other digital devices to experience symptoms of dry eye. To mitigate this, it's recommended to follow the 20-20-20 rule: every 20 minutes, take a 20-second break and look at something 20 feet away.

When to Consult a Doctor for Dry Eye

While occasional dry eye symptoms can be managed with over-the-counter eye drops or lifestyle changes, it's important to consult a doctor if you have persistent dry eyes. A healthcare professional can help determine the cause of your dry eyes and recommend the most effective treatment options for your specific situation.

Persistent dry eyes can cause discomfort and interfere with daily activities. In some cases, it can also lead to more serious complications such as corneal ulcers or vision loss. Therefore, it's crucial to seek professional help if your dry eye symptoms persist or worsen.


Understanding what causes dry eyes is the first step towards finding relief. While the causes can be varied, ranging from medical conditions to long-term contact lens use, it's clear that numerous factors can contribute to this common condition.

Dry eye doesn't have to interfere with your quality of life. By understanding the causes and seeking professional help when needed, you can manage your symptoms and maintain your eye health.

For more information on what causes dry eye, visit Vintage Optical in Morton, Illinois. Call (309) 263-8611 to discuss any questions with our team of experts or to schedule an appointment today.