Multiple reasons can cause dry eyes. Generally, the classical causes are the decreased tear production and increased evaporation of tears. The former commonly results from blepharitis, atopic dermatitis, rosacea, or seborrhoeic dermatitis, especially some allergic conjunctivitis. While the later is usually attributed to low humidity central followed heating, air conditioning or high wind conditions and low blink rate, particularly your wide lid aperture due to the long time use of a computer or something like, relating to eye stain. Furthermore, we can not deny the sodium that influence our eye health status, but in reverse, people who are depleted by eating refined sugar, as well as excess sodium from junk foods are prone to suffer eye dryness.