As an avid contact wearer, I use saline solution to rinse my contacts daily before each use. Recently, a friend told me that many commercial saline solutions contain preservatives, which could affect the overall health of my eye. Is this something I should be concerned about? The saline I use has always felt comfortable so I never thought it could pose a problem.

I go through phases where, when I sleep, I don't have any dreams (that I remember, at least). I sleep well and I wake up rested. Every few months I go through a week or two when I have nights full of incredibly vivid dreams and I wake up remembering at least five or six of them. Because of all these vivid dreams, I wake up feeling far less rested than I do when I don’t dream at all. Is there a particular reason for this? Does dreaming more at night mean your sleep is less restful?

I read that disposable contact lenses are actually worse for your eyes than the normal one-year ones because they allow less oxygen to go to your eyes, and the only advantage is that there are less cleansing problems. Also, it is claimed that inadequate oxygen to your eyes (possibly caused by prolonged wearing of contact lenses) leads to a condition when extra blood vessels sprout around the iris, which leads to sight problems at old age. Is that true?

I am very concerned because I normally wear (one-year) contact lenses from 8am to 8pm, and maybe to 12am during reading periods. I don't feel very comfortable with glasses because they give distorted visions and fatigue. I thought switching to disposable contact lenses would do my eyes good. My current lenses contain 38 percent water. Is this good enough?

Dear Alice,

Is it dangerous to sleep in your soft disposable contact lenses for one night if you can't get them out?

My eyes are light-brown, and when I've been crying or when it's bright outside they look greenish. I want my eyes to be that greenish all the time. I heard that putting honey in your eyes will lighten them. Are there any side effects? Is it bad for my eyes?

Lately, I've come to realize that I have a very powerful tendency to fall asleep in class. It seems that I can't stay awake in any lecture style class where I have to listen to the professor and take down notes — where there is minimal engagement on my part. I've pretty much fallen asleep in all of my lecture classes, during one part or another for the whole semester. I think I'm getting regular sleep — six hours at a minimum. I don't like to drink coffee or anything.