How do tears protect your eyes?

Each time we blink, a protective coating of tears is spread like a film over our eyes. This is known as the tear film. The tear film ensures hydration of the ocular surface and washes away dust and particles than can come into contact with your eyes.1

An unstable tear film is the main cause of dry eye disease.
Normal and Dry eye
Healthy eyes (Stable tear film)
Healthy eyes (Stable tear firm)
Dry eye (Unstable tear film)
Dry eyes (Stable tear firm)
Photo provided by Dr. Takashi Hamano, Hamano Eye Clinic
The tear film is important for eye protection as it keeps the surface of the eyes smooth and clear, and reduces the risk of eye infection.


  • 1. Dwivedi M et al. Biophysical in of the structure and function of the tear fluid lipid layers and the effect of ectoine. Part B: Artificial lipid films. Biochimica et Biophysica Acta 1838 2014;2716–2727.