Your eyes get dry when the thin film of tears coating their surface breaks down or isn’t produced in sufficient quantity. This is remarkably common: a 2025 meta-analysis covering over 15 million participants found that roughly 35% of people worldwide experience dry eye. The condition is more prevalent in women (39%) than men (31%), and rates climb after age 40. Understanding what disrupts your tear film helps explain why dryness happens and what you can do about it.
How Your Tear Film Works
Every time you blink, you spread a three-layered film across the surface of your eye. The outermost layer is oily, produced by tiny glands along your eyelid margins called meibomian glands. Beneath that sits a watery layer, which makes up the bulk of your tears and comes from the lacrimal glands above each eye. The innermost layer is mucus, which helps the watery layer spread evenly and stick to the eye’s surface.
Each layer has a job. The oily outer layer acts as a seal, slowing evaporation of the watery layer underneath. The watery middle layer delivers oxygen and nutrients to the cornea, flushes out debris, and fights infection. The mucus base keeps the whole structure anchored. A problem in any one of these layers can leave your eyes feeling gritty, burning, or irritated.
The Most Common Cause: Oil Gland Problems
The leading driver of dry eyes is dysfunction in the meibomian glands. These glands line the edges of your upper and lower eyelids, and when they become blocked or produce poor-quality oil, the protective outer layer of your tear film thins out. Without that oily seal, the watery layer evaporates too quickly. You might have plenty of tear production and still feel dry because the tears aren’t staying on your eye long enough.
Meibomian gland dysfunction becomes more common with age. The glands can become clogged by thickened secretions, inflamed by skin conditions like rosacea, or gradually damaged over time. People who wear contact lenses or eye makeup frequently are also at higher risk. The result is the same: tears evaporate faster than they should, and the eye surface dries out between blinks.
Screens and Blinking
You normally blink about 15 times per minute. During screen use, that rate drops to just 5 to 7 blinks per minute. Since each blink refreshes the tear film, cutting your blink rate by more than half means your tears have longer to evaporate before being replenished. This is why your eyes often feel worst at the end of a long workday or after hours of scrolling.
The problem compounds in certain environments. Air conditioning, heating, airplane cabins, and fans all accelerate evaporation. Working at a screen in a dry, climate-controlled office is essentially a perfect storm for tear film breakdown.
Hormones and Aging
Hormonal shifts play a significant role, particularly for women. The meibomian glands are sensitive to androgens (hormones like testosterone), which help regulate the quality of the oily tear layer. When androgen levels drop, as they do after menopause, the glands can produce less effective oil. Women who have had their ovaries removed, or who have conditions affecting adrenal or pituitary function, face a similar risk.
This hormonal connection helps explain the gender gap in dry eye prevalence. It also explains why many women notice dry eyes worsening in their late 40s and 50s, even without other obvious triggers. Aging independently reduces tear production as well. The lacrimal glands gradually produce less of the watery tear component over time, regardless of sex.
Medications That Reduce Tear Production
In older adults, medications account for a striking share of dry eye cases. Research from the Tear Film & Ocular Surface Society estimates that 62% of dry eye in the elderly can be traced to systemic medications. The list of culprits is long: antihistamines, antidepressants, blood pressure medications, diuretics, anti-anxiety drugs, and common pain relievers all make it.
Many of these drugs share a property called anticholinergic activity. In plain terms, they interfere with chemical signals that tell your tear, mucus, and oil glands to secrete. The dry eye effect is often unintentional, a side effect of blocking those signals elsewhere in the body. If you take multiple medications from this list, the drying effects can stack. Switching to alternatives isn’t always possible, but knowing the connection helps you and your doctor manage symptoms more effectively.
Autoimmune Conditions
Some people develop dry eyes because their immune system attacks the glands responsible for moisture. Sjögren’s syndrome is the most well-known example. In this condition, immune cells infiltrate the lacrimal and salivary glands, gradually destroying their ability to produce tears and saliva. The hallmark combination is persistently dry eyes and a dry mouth.
Sjögren’s can occur on its own or alongside other autoimmune diseases like rheumatoid arthritis and lupus. When it develops secondary to another condition, the dry eye component is sometimes overlooked or attributed to aging. The dryness from Sjögren’s tends to be more severe and persistent than typical dry eye, often requiring more intensive treatment.
What Dry Eyes Feel Like
Dry eye symptoms aren’t always intuitive. Beyond the obvious sandy, gritty sensation, you might experience burning, stinging, redness, or a feeling that something is stuck in your eye. Blurry vision that clears when you blink is another common sign, caused by an uneven tear film distorting light as it enters the eye.
Paradoxically, watery eyes can also signal dryness. When the eye surface becomes irritated from poor tear film coverage, it triggers a reflex flood of watery tears. These emergency tears lack the balanced oil-mucus-water composition of normal tears, so they wash over the eye without actually relieving the dryness. If your eyes water constantly but still feel irritated, dry eye is a likely explanation.
How Dry Eye Is Diagnosed
Eye doctors assess dry eye with a few straightforward tests. One measures how quickly your tear film breaks apart after a blink. A normal breakup time is 8 to 10 seconds or longer. If the tear film fractures in 2 to 3 seconds, that suggests significant dryness from too little watery tear production. Patterns of where and how the tear film breaks can also tell a clinician whether the problem is mild or severe, and whether it’s driven by oil deficiency, water deficiency, or both.
Managing Dry Eyes Day to Day
Artificial tears are the first-line approach for most people. Over-the-counter lubricating drops come in two main types: preserved and preservative-free. If you’re using drops four times a day or less, preserved formulas are generally fine. If you need them more frequently, switch to preservative-free drops, as the preservatives themselves can irritate the eye surface with repeated use.
For screen-related dryness, the simplest intervention is deliberate blinking. The 20-20-20 rule works well: every 20 minutes, look at something 20 feet away for 20 seconds, and consciously blink several times. Positioning your monitor slightly below eye level also helps, as it narrows the opening between your eyelids and reduces the exposed surface area where tears evaporate.
Omega-3 fatty acids may improve tear film stability. Clinical studies have used doses of 360 milligrams of EPA and 240 milligrams of DHA daily (typically split into two doses) and found benefits for some patients. Fish oil or algae-based supplements at these levels are widely available. Results aren’t dramatic for everyone, but for people with mild to moderate symptoms, they can be a useful addition.
Warm compresses applied to closed eyelids for 5 to 10 minutes can help soften clogged meibomian gland secretions, improving oil flow. This is especially helpful if your dryness stems from the evaporative type. Doing this daily, followed by gentle lid massage, can gradually restore better oil production. For more stubborn cases, in-office procedures can express the glands more thoroughly.
Environmental adjustments matter too. A humidifier in your bedroom or workspace counteracts dry indoor air. Wraparound glasses or moisture chamber eyewear can reduce tear evaporation outdoors, particularly in windy or arid climates. Small changes to your surroundings often deliver more consistent relief than drops alone.