I cannot confirm that it is at all diet related. It started after around 8 months of being strict paleo and there was no sudden diet change around the time it started occurring.
It has caused recurrent corneal erosions. I have to keep my eyes closed upon waking and put moisturizing drops into the corners before I open them to avoid the erosions (doctor's orders). This is anytime I wake up, even only 2 hours after falling asleep my eyes will be this dry. I occasionally take 3mg of melatonin before bed, but have not noticed any difference in eye dryness whether I do or don't take it.
Things I have tried so far: 1) Using moisturizing 'oil' for eyes before going to sleep. Got it at the drugstore, didn't help at all. 2) Drink a big glass of water before bed to make sure I'm hydrated. This just makes me have to pee in the middle of the night, before which I must go through the process of putting in drops so I can open my eyes! 3) Being very, very certain that my eyes are completely closed while falling asleep. I was told that dry eyes can be caused by the eyes being partially open during sleep. No help.
Also, I do wear contacts/eyeglasses and notice no difference whether I wore contacts that day or not.
Any ideas? I know there was no sudden diet change around when it started happening, but I am inclined to think it must be in some way diet/specific food related.