A reader asks:

 Hello, I have been using a light box for just over three weeks now. Initially I simply used it when I naturally woke-the first week was at the end of the summer holidays so average time to find myself sitting in front of the box was 9am. After about a week I discovered your website, took the AutoMEQ and discovered the time I needed to be using it was 530am. I weaned myself back to this time over the following 5 days. My principal drive for using light therapy is avoidance of SAD symptoms and so I based my overall time of initiation of therapy on my wish to avoid SAD creeping in at all this autumn; I actually feel that because of the dreadful summer Ireland has had this year, that my mood and energy levels did not get their customary boost during the ‘brighter’ months. So, my main question is, how long will it take to adjust my circadian rhythm to the point where waking at 5:15 happens without an alarm clock? Additionally, should I miss a morning (for example, at the weekend), does this cause disruption to the pattern I’m attempting to establish?


The difference between your spontaneous (late) wake-up at 9am and your goal, 530am, is large. The adjustment should be made more slowly. You should begin light therapy 30 minutes before your current wake-up time (in this case 830am), and stick with it until your wake-up has advanced by 30+ minutes. This may take several days, although sometimes it will happen in 1-2 days. At that point, shift light therapy another 30 min until you are stabilized at 8am. Continue this sequence until you reach 530 am, making sure you have adjusted comfortably at each step. It is possible that you will feel the full effect before reaching 530am, in which case you can maintain the later wake-up time (for example, 630am). Skipping a single day over the course of a week should not be seriously disruptive, but if you were routinely to skip whole weekends, your circadian clock will quickly shift later, and you may even have to back-track (for example, from 7am to 8am), if you have difficulty waking up on Monday morning, and proceed from the later hour.

Obviously, there is a risk of significantly slower adjustment if you skip days frequently. It would be helpful if you maintained a log (downloadable from Dropbox link http://ow.ly/VYgDW), which will help you review your rate of progress and identify possible disruptive influences. Bottom line: if the AutoMEQ advises waking up for light therapy more the one hour before your current wake-up time, you should approach the goal in small steps, waiting to adjust at each step.