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?

The muscles in my back become extremely tense/tight throughout the term as I am cramped down studying all the time. What should I do?

Do men need to cover up their testicles when using indoor tanning facilities?

I use tanning booths regularly and I normally use only eye protection. I am slightly worried, however, that the UV radiation from the sunlamps could do internal damage to a man's testicles, because the skin is obviously only very thin and might not offer much protection against UV radiation. Since eyelids are similarly thin and it is known that eye damage can result even when using tanning equipment with closed eyes, I wonder if advice should be given to men to use similar precautions to prevent testicles being exposed to high-intensity UV-A or UV-B radiation. I have looked everywhere for scientific information on this matter but could not find anything. Your advice on this matter would therefore be very much appreciated.

Is there any chance that because I get low blood sugar occasionally, I may become a diabetic someday? And what can you keep with you to take when your levels do drop, and you can't get to any food or juice?

When is a person with a cold contagious? A couple of friends, who are put off when I keep my distance from their sneezing and coughing, insist one is only contagious a week or so before symptoms appear. In the back of my memory is the idea that one remains contagious until a few days *after* primary symptoms disappear. I'm not usually so concerned about this, but I'm coping with a couple of other annoying health problems and want to try to avoid adding a cold or flu, to boot. I do the usual things news shows recommend — eat well, wash hands frequently. But when should one avoid others who have colds, or when should one stay isolated at home when one has a cold (or flu)?

I have recurring insomnia which lasts for about eight to twelve days. It seems to begin at about the same time each month. What are the common causes of sleep disturbance? Any suggestions?

I've been hearing a lot on the news about the new virus [novel coronavirus, COVID-19] and I'm seeing students on campus wearing masks. The news seems to have conflicting information and I'm not sure what to do. Should I be worried? Do I need to wear a mask too? Thank you.