Tears

Tears are not simply a mix of water, electrolytes, and minerals.  They have an architecture.  “Tear film consists of three layers: in order from the outside, these are the tear film lipid layer (TFLL), the aqueous layer, and the glycocalyx. The TFLL contributes to the suppression of water evaporation from the aqueous layer and reduces the surface tension of tears   Since the TFLL lipids are secreted from the meibomian glands, which are distributed behind the eyelids, they are collectively called meibum lipids. The aqueous layer contains nutrients, electrolytes, and bioactive molecules. The mucin-rich glycocalyx layer has a role in maintaining the aqueous layer on the corneal surface.” Lipid polarity of these layers prevents dry eye disease, as researchers at Hokkaido University in Japan have found.  MORE

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