University Heights, OH (PRWEB) August 20, 2012
During the course of the summer, many teenagers develop the habit of staying up later and later. By now they are staying up ‘till 3 or 4 A.M. and sleeping until noon. During this time their internal or circadian clock has adjusted so it is set about five hours later than the clock on the wall. Between now and when school starts it needs to be moved back those 5 hours.
The classic way to adjust the internal clock (1) is to expose the eyes to bright light on waking. It is most effective to move the clock a little at a time. If school starts the day after Labor Day, divide the 5 hours by how many days remain between now and Labor Day to get how much you need to accomplish each day. To use the classic method requires you wake up your youngster that many minutes earlier each morning and get him/her into bright light. Realistically, this just isn’t going to happen.
The modern way (2) to advance the circadian clock works on the time when melatonin starts flowing after going into darkness. By moving the time of going into darkness a little earlier each night, the same effect can be obtained. Getting your teen to go to bed earlier each night is also an impossible task.
Fortunately, in 2001, scientists in this country (3) and in the UK (4) reported an astounding finding. There are special light sensitive cells in the retina of the eye that are different from the rods and cones. They have nothing to do with vision. They control the circadian clock and the production of melatonin. The special cells respond most strongly to blue light. Dr. Kayumov and his colleagues at the University of Toronto found (5) that subjects wearing blue blocking glasses produced melatonin during the night even though exposed to bright light, just as they had when in darkness on an earlier night.
In 2005, physicists at John Carroll University developed light bulbs that don’t make blue light and eyeglasses that block it. They are available through a spin off company at http://www.lowbluelights.com.
All your student needs to do is put on a pair of the glasses or switch on special light bulbs some number of minutes earlier each night starting a bit ahead of the most recent bedtime. This will gradually advance the circadian clock to an earlier hour. Whether he/she actually starts going to bed earlier is not required. Because the flow of melatonin is starting a bit earlier each night, going to bed earlier may just happen, without a fight.
Getting up earlier and exposing the eyes to light should be encouraged. You need all the help you can get. Providing breakfast outside is a good strategy for make this happen in a pleasant way.
Few plans work perfectly. The first day of school is still not likely to be easy. The good news is that this trick of using the light bulbs or glasses can be used to keep advancing the circadian cycle to an earlier hour. By getting to where you are putting on the glasses two or more hours ahead of bedtime, you will have lots of melatonin present, by bedtime. This allows sleep to come quickly. Melatonin can only flow for about 10 or 11 hours (6). Starting earlier means ending earlier. Your student may actually be wide awake and ready to learn by the time his/her first class begins.
You may find this trick is also good for you and the rest of the family. There is a very significant side effect. Maximizing melatonin is likely to reduce your risk for breast cancer and, very likely, other cancers (7). There does not appear to be any down side to eliminating blue light in the evening. For millions of years before we had electric lights we didn’t have blue light at night. Using special light bulbs or wearing the glasses allows us to go back to that peaceful time.
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