Since part of their water evaporates they practically dehydrate your eye by absorbing water on your natural tear film since the eye. It is usually during periods of high concentration (such like front of computer) when a person blinks less and can then be begins to complain of dry eyes. https://Www.google.dk/url?q=https://www.theralife.com/is-dry-eye-a-cause-of-headaches/