Dry Eye Causes
If we cannot produce enough tears, or the tears we do produce do not contain enough oil, water, or mucin, our eyes become dry and irritated.
Inadequate Tear Volume
Our tears are produced by several different glands, which are located in and around our eyelids. As we age, our eyes may not produce as many tears, which leads to dry eyes. Certain medical conditions and medications can also affect our ability to produce enough tears to keep our eyes lubricated.
Even if our eyelids can produce enough tears to meet our needs, environmental factors, such as a dry climate or wind, can cause our tears to evaporate too quickly.
Poor Tear Quality
Our tears are composed of three substances: an oil called meibum, water, and mucin.
- Meibum keeps our tears from evaporating too quickly by forming a thin, protective coating over the tear’s surface.
- Water helps keep our eyes hydrated and comfortable. If our tears evaporate too quickly, or our eyes cannot uniformly distribute our tears, it can cause dry eyes.
Mucin ensures that our tears form an even coating across the cornea.