You know it.  You’ve been told that you should turn off your electronic equipment 30 minutes (at least) before you go to sleep.  To help your brain get ready for sleep.

(OK.  This is where I have to interject this is clearly a “do as I say and not as I do” item.   I literally play scrabble on my tablet, read my mail, and watch the news up until the second I turn over to go to sleep.  And, I fall asleep right away.   And, I sleep 3.5 to 4.2 hours a night.   Waking up bright-eyed and bushy-tailed.  [Right.  Clearly the former’ no tails here.] But, back to the “official recommendations”.)

Our body works off circadian rhythms.  The Suprachiasmatic Nucleus (a portion of the hypothalamus) is where our body’s master timekeeper, the keeper of our circadian clock resides.  And, while our circadian clock is longer than 24 hours, it’s only when it’s significantly different from that of our environment that it makes a big difference.

So, when I (I’m being honest here) worked a 30 hours day, when the environment has significant light- my clock can become upset.  (This is why I sometimes felt it was easier to put in a 40 hour day than a 20 hour day, since my clock was so significantly upset, it was almost reset to normal).  And, when the clock is upset, our hormonal balances become discordant.

Our hormones work off that circadian rhythm also- which is why it is really bad to eat a full meal after 10 pm and go right to sleep.   That meal’s calories often become the dead weight of our bodies.  (In other words, we don’t properly metabolize them.)

But, the environmental darkness is critical to reset our clock.  It affects the melatonin flow- which we need more when we sleep. And, when we are exposed to light, our melatonin production decreases.

So, now you know why you are supposed to turn off those computer monitors, those tablets, the lights, etc.   So our brain- and our hormonal levels are attuned to the needs of our sleep.

And, it becomes more critical when we consider the work of Dr. Kenneth Wright (University of Colorado, Sleep Laboratory).  He published recently in Current Biology (co-authors AW McHill, BR Birks, BR Griffin, and T Rusterholz) “Entrainment of the Human Circadian Clock of the Natural Light-Dark Circle”.

The study involved eight healthy adults, equipped with actigraphs (which they wore for one week before their special camping trip).  The actigraph on their wrists measured their sleep, their movements, and ambient light exposure.  After this baseline (control) determination, their vitals (as they concerned circadian rhythms, which included hormonal levels) were determined.

Then, the fun began.  These folks were sent on camping trips for a week- where no flashlights, electricity, etc. were allowed.   They were left with their tents, sunlight, campfires, and night skies.  All artificial light exposures were denied.  (They still had their wrist actigraphs.)  And, then their “circadian vitals” were once again examined.

Not surprisingly, the subjects produced melatonin about 2 hours earlier than when they were not deprived of artificial light- and began dropping about 1 hour prior to their arising in the morning.  (These levels didn’t drop until the subjects were up for an hour or so when they operated in artificial light conditions.)

These light bulbs may be what we need in our bedrooms. NOTE: I will be discussing these sorts of devices in a much later blog.

So, there you have it.   If you think you are having problems sleeping, cut off all your external light exposure at least an hour before you want to sleep.  (And, if you really want eight hours of sleep, that means 9 hours before you plan to awake.)  I can see a few of my friends adopting a new protocol- mellowing out on their decks under the skies before they plan to sleep.   Right, Andy?