The causes of dry eye
Poor tear quality:
Healthy tears contain a balance of three layers: oil, water, and mucus. Oil minimizes tear evaporation. Water cleanses the eye and carries oxygen to the ocular tissue. Mucus keeps tears spread evenly and stabilizes the tear film. Diminished quality of any of these layers, and you’ll suffer from dry eyes. Research shows that up to 85% of dry eye sufferers have poor tear quality due to Meibomian Gland Dysfunction (MGD).
Low quantity of tears:
Tears are produced by glands in and around the eyelids. A decreased quantity of tears results from not producing enough tears to moisten your eyes. Many factors can impact tear production.
Factors associated with dry eye
There are many factors that can increase your risk for dry eye, including:
Age—While dry eye can occur at any age, risk increases with aging especially after age 50.
Gender—Women are more likely to develop dry eyes because of hormonal changes that occur during pregnancy and menopause.
Health conditions—People with diabetes, thyroid problems, lupus rheumatoid arthritis and Sjogren’s syndrome are more likely to experience dry eye. Also, inflammation of the eyelids (blepharitis), or surfaces of the eye, or the inward or outward turning of eyelids can lead to dry eyes.
Medications—Both prescription and over-the-counter medicines like antihistamines, decongestants, blood pressure medications, antidepressants and oral contraceptives, can reduce tear production.
Environmental conditions—Smoke, wind and dry climates can increase tear evaporation causing dry eye symptoms.
Computer use—People tend to blink 60% less when using electronic devices and computers for long periods of time, which can also contribute to drying of the eyes.