Dry Eye Causes and Risk Factors: Complete Guide [2026]
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Dry Eye Causes and Risk Factors [Complete Guide 2026]
Wondering why you have dry eyes? Have you noticed that symptoms worsen in certain situations but don't know why? Understanding the causes of dry eye is the first step to finding the most effective treatment for your case.
Dry eye doesn't appear out of nowhere. There are specific factors that affect how you produce tears and their quality. According to recent studies, more than 80% of cases are related to meibomian gland dysfunction, but there are many other causes that could be affecting you without you knowing.
If you already recognize dry eye symptoms, you can read our complete symptoms guide here.
In this complete guide, you'll discover the main causes of dry eye, the risk factors that increase your likelihood of developing it, and what you can do to prevent or improve this condition.
Why Does Dry Eye Happen?
To understand dry eye causes, you first need to understand how the tear film works.
The tear film has three layers:
- Lipid layer (oil): Produced by meibomian glands in the eyelids. Prevents tears from evaporating too quickly.
- Aqueous layer (water): Produced by the main lacrimal glands. It's the thickest layer and provides moisture and nutrients.
- Mucin layer: Produced by conjunctival cells. Helps tears distribute evenly over the eye.
When any of these three layers fails, dry eye appears.
The 2 Main Categories of Dry Eye
1. Evaporative Dry Eye (86% of cases)
What it is: Tears evaporate too quickly because the oil layer is insufficient or poor quality.
Main cause: Meibomian gland dysfunction (MGD).
How it happens: Meibomian glands get clogged with thick secretions. This prevents them from producing the necessary oil to protect tears, which evaporate in seconds instead of minutes.
This is the most common type of dry eye and responds best to treatments like heat therapy (Nichols et al., 2011).
2. Aqueous Deficient Dry Eye (less than 20%)
What it is: Lacrimal glands don't produce enough aqueous tears.
Main causes:
- Sjögren's syndrome (autoimmune disease)
- Advanced age (natural decrease)
- Damage to lacrimal glands from radiation or surgery
Main Causes of Dry Eye
1 Meibomian Gland Dysfunction
What they are:
Meibomian glands are sebaceous glands located on the eyelid margins. Each eyelid has between 25 and 40 glands.
Why they get clogged:
- Secretions become thick like cold butter, when they should be liquid like oil
- Chronic eyelid inflammation (blepharitis)
- Bacteria colonizing the eyelid margin
Factors that worsen MGD:
- Prolonged screen use (you blink less, glands don't "squeeze" properly)
- Makeup that clogs glands
- Age (meibum quality decreases over time)
- Hormonal changes (menopause, low androgen levels)
Prevalence:
of dry eye patients have meibomian gland dysfunction (Craig et al., 2017)
💡 IMPORTANT FACT
If you have meibomian gland dysfunction (like 86% of people with dry eyes), heat therapy can help you address the root cause of the problem.
Applying consistent heat at 42°C (107.6°F) for 15 minutes helps liquefy thick meibomian gland secretions, as described in ophthalmology studies.
IRIO ONE applies this temperature consistently for the recommended time, following parameters mentioned in scientific literature.
→ Discover how it works2 Excessive Screen Use
The problem:
When you look at a screen (computer, phone, tablet), your blink rate decreases dramatically. To learn more about this phenomenon, see our guide on digital eye strain.
Scientific data:
Normal blink rate: 15-20 blinks/min
On screens: 5-7 blinks/min
(Tsubota & Nakamori, 1993)
Why it affects you:
- Less blinking = less tear film renewal
- Less blinking = meibomian glands don't "squeeze" properly
- Greater tear evaporation from keeping eyes more open
Most affected population:
Office workers, programmers, graphic designers, gamers, students.
3 Age
Reality:
Dry eye risk increases significantly with age.
Why it happens:
- After 50: Lacrimal glands produce less aqueous tears
- After 40: Meibomian glands produce poorer quality secretions
- During menopause (women): Hormonal changes directly affect tear production
Data:
- People over 50 are 3 times more likely to develop dry eye
- In those over 65, prevalence exceeds 30% (Schaumberg et al., 2003)
4 Hormonal Changes
Hormones and tears:
Sex hormones (estrogen, androgens) regulate tear production and quality.
Risk situations:
Menopause:
- Decreased estrogen affects lacrimal glands
- Higher risk of severe dry eye
- Up to 61% of postmenopausal women report symptoms (Sullivan et al., 2014)
Hormone replacement therapy (HRT):
- Paradoxically, can WORSEN dry eye in some women
- Especially estrogen-only therapies
Oral contraceptives:
- Some types can reduce tear production
- Varies by hormonal formulation
Low androgen levels:
- Androgens are essential for meibomian gland function
- Low levels = higher MGD risk
5 Medications
Certain medications reduce tear production as a side effect.
Medications most commonly causing dry eye:
Antihistamines:
- Used for allergies
- Dry all mucous membranes, including tears
- Examples: loratadine, cetirizine
Antidepressants:
- Especially tricyclics and SSRIs
- Examples: amitriptyline, fluoxetine, sertraline
Anti-anxiety medications:
- Examples: diazepam, alprazolam
Antihypertensives:
- Especially beta-blockers
- Examples: atenolol, metoprolol
Isotretinoin (for acne):
- One of the most drying medications
- Directly affects meibomian glands
- Dry eye can persist even after stopping treatment
6 Autoimmune Diseases
Sjögren's syndrome:
- Most common autoimmune cause of dry eye
- Immune system attacks lacrimal and salivary glands
- Symptoms: SEVERE dry eye + dry mouth
- More common in women (90% of cases)
- Diagnosis: Blood tests + salivary gland biopsy
Other associated autoimmune diseases:
- Rheumatoid arthritis: Up to 30% develop dry eye
- Systemic lupus erythematosus
- Scleroderma
- Thyroid disease (Graves, thyroiditis)
7 Environmental Factors
Dry air:
- Low humidity environments (less than 30%)
- Heating and air conditioning
- Desert or mountain climate
Wind:
- Increases tear evaporation
- Especially problematic for motorcyclists, cyclists
Smoke:
- Cigarette smoke (active and passive smokers)
- Smoke from fireplaces, kitchens
Pollution:
- Pollutant particles irritate the eye surface
- Cities with high pollution = higher dry eye prevalence
Altitude:
- Higher altitude, lower humidity
- Frequent air travelers (very dry cabins)
8 Contact Lens Use
Why lenses cause dry eye:
Contact lenses can significantly worsen dry eye symptoms. For a detailed explanation of this relationship, see our complete guide on contact lenses and dry eye.
- Absorb the tear film
- Reduce oxygen reaching the cornea
- Increase tear evaporation
- Accumulate protein deposits that irritate the eye
Data:
- Up to 50% of lens users report dryness discomfort
- It's the main reason for contact lens abandonment
Factors that increase risk:
- Extended wear (more than 10 hours daily)
- Low oxygen permeability lenses
- Poor maintenance
- Sleeping with lenses on
9 Eye Surgeries
LASIK and refractive surgery:
- Dry eye is the most common post-LASIK side effect
- Corneal nerves are cut during the procedure
- Nerves take 6-12 months to regenerate
- In some cases, dry eye can be permanent
Cataract surgery:
- Can cause temporary dry eye
- Generally improves in 3-6 months
Blepharoplasty:
- Can affect eyelid function
- Risk of lagophthalmos (eyelids that don't close completely)
10 Blepharitis and Eyelid Problems
Blepharitis:
- Chronic inflammation of eyelid margins
- Causes: Bacteria, Demodex mites, seborrheic dermatitis
- Symptoms: Crusty eyelashes, redness, burning
- Blepharitis worsens meibomian gland function
Eyelid position problems:
- Ectropion: Lower eyelid turns outward
- Entropion: Eyelid turns inward
- Lagophthalmos: Eyelids don't close completely
11 Ocular Surface Diseases
Ocular rosacea:
- Ocular extension of skin rosacea
- Chronic eyelid and eye surface inflammation
- Highly associated with MGD
Exposure keratitis:
- Corneal inflammation from eye exposure to air
- Common in people with exophthalmos or eyelids that don't close well
Vitamin A deficiency:
- Rare in developed countries
- Causes severe dry eye + night vision problems
Risk Factors: Who's More Likely?
You're MORE LIKELY to develop dry eye if:
The more factors you have, the higher your risk.
💡 OPHTHALMOLOGIST'S TIP
If you identify 3 or more risk factors in your case, it's important to take preventive measures now, even if your symptoms are still mild.
Heat therapy can help prevent worsening of meibomian gland dysfunction. According to ophthalmology studies, applying heat at 42°C (107.6°F) for 15 minutes can improve meibomian secretion quality before severe dry eye develops.
IRIO ONE applies consistent heat at 42°C (107.6°F), following parameters described in scientific literature for preventive meibomian gland care.
→ Discover how IRIO ONE worksPrevention: Can You Avoid Dry Eye?
While you can't control factors like age or genetics, you CAN significantly reduce your risk with these habits:
10 Effective Preventive Measures
- 20-20-20 Rule for Screens
Every 20 minutes, look at something 20 feet away for 20 seconds. This forces you to blink more and reduces eye strain. - Conscious Blinking
Take breaks every hour to blink completely 10 times in a row. This redistributes tears and squeezes meibomian glands. - Humidifier
Maintain ambient humidity between 40-60%, especially if using air conditioning or heating. - Eye Protection
Wear wraparound sunglasses outdoors. Consider computer glasses with blue light filter. Avoid direct air currents on your face. - Daily Eyelid Hygiene
Clean eyelid margins 1-2 times daily with special wipes or diluted baby shampoo. - Omega-3
Supplements of 1000-2000 mg daily of EPA+DHA can improve secretion quality. Benefits visible in 2-3 months. - Hydration
Drink 2-2.5 liters of water daily. General hydration affects tear production. - Avoid Smoking
Tobacco smoke is one of the most potent irritants for the eye surface. - Review Your Medications
Ask your doctor if less drying alternatives exist. - Preventive Heat Therapy
If you have risk factors, applying heat 2-3 times weekly can prevent meibomian gland clogging. IRIO ONE lets you apply this heat therapy effectively at home.
When Do Causes Require Medical Treatment?
Consult an ophthalmologist if:
- You suspect you have an autoimmune disease (generalized dry symptoms: mouth, skin, eyes)
- Your dry eye appeared after eye surgery
- You have blepharitis that doesn't improve with home hygiene
- Your symptoms are severe and don't respond to artificial tears
- You notice vision changes
The ophthalmologist can:
- Diagnose the specific cause of your dry eye
- Perform tear function and meibomian gland tests
- Rule out underlying diseases
- Prescribe specific treatments for your case
For detailed information on all available treatments, see our comprehensive guide on dry eye treatment.
Frequently Asked Questions About Dry Eye Causes
What's the most common cause of dry eye?
Meibomian gland dysfunction (MGD) is the primary cause, present in 86% of dry eye cases. These glands produce the tear oil layer that prevents evaporation.
Does screen use cause dry eye?
Yes. Prolonged screen use reduces your blink rate from 15-20 times per minute to just 5-7 times per minute, increasing tear evaporation and worsening meibomian gland function.
Is dry eye hereditary?
There are some genetic factors that can predispose to dry eye, but lifestyle (screen use, environment, medications) plays a much more important role than genetics in most cases.
Can birth control pills cause dry eye?
Yes, some oral contraceptives can reduce tear production due to hormonal changes they produce. However, the effect varies by specific hormonal formulation.
Can dry eye be prevented?
Yes, even with risk factors. With eyelid hygiene, the 20-20-20 rule for screens, humidifier use, and preventive heat therapy, you can significantly reduce the likelihood of developing symptomatic dry eye.
Conclusion
Dry eye rarely appears without reason. In most cases, there are one or several identifiable causes behind your symptoms.
The most common causes are:
- Meibomian gland dysfunction (86% of cases)
- Excessive screen use
- Age and hormonal changes
- Medications
- Environmental factors
Identifying what's causing YOUR dry eye is essential to finding the most effective treatment. If you recognize several of these causes in your situation, don't wait for symptoms to worsen. Preventive measures and early treatment can prevent dry eye from progressing to more severe and disabling forms.
Want to Address the Root Cause of Dry Eye?
If your dry eye is caused by meibomian gland dysfunction (like 86% of cases), IRIO ONE can help.
Our thermal eye mask applies consistent heat at 42°C (107.6°F) for 15 minutes, following protocols described in ophthalmology studies to improve meibomian gland function.
- Helps treat the cause, not just symptoms
- Consistent heat at scientifically-backed temperature
- Easy to use at home
Disclaimer: This information is for educational purposes and does not replace professional medical advice. IRIO ONE is not a medical device. Always consult with an ophthalmologist for diagnosis and treatment of eye conditions.
References
For all complete scientific references supporting this article, visit our Scientific References page.
- Craig JP, et al. TFOS DEWS II Report. Ocul Surf. 2017;15(4):802-812.
- Nichols KK, et al. MGD international workshop. Invest Ophthalmol Vis Sci. 2011;52(4):1917-1929.
- Tsubota K, Nakamori K. Dry eyes and VDT. N Engl J Med. 1993;328(8):584.
- Schaumberg DA, et al. Prevalence among US women. Am J Ophthalmol. 2003;136(2):318-326.
- Sullivan DA, et al. Hormones and lacrimal gland. Endocr Rev. 2014;35(5):779-831.
- Lemp MA, et al. Dry eye distribution. Cornea. 2012;31(5):472-478.
Written by Dr. A. Messadi