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 have been a Type II diabetic for several years. I am now told I am beginning to show kidney insufficiency — is there a diet, or can you tell me where to find diet information of foods that a diabetic can use that are lower in protein and/or a renal diet?

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?