Ask SleepBetter: Sleeping in Shifts

Have you wondered about something related to sleep, but just can’t find the answer? Lots of people do, and that’s why we created Ask SleepBetter. You can ask your own question on the SleepBetter Facebook Page, or by using our Ask SleepBetter contact form. We will try to answer as many questions as possible, but we are not able to answer queries about physical issues or medicinal issues. Those should be addressed face-to-face with a physician.

Today’s question is about sleeping in shifts:

“I am planning to nap for 2 hours after dinner, from 8:30 p.m. to 10:30 p.m., then stay awake till past 1 a.m., then sleep again until 6 a.m. Is this kind of sleep cycle bad for my health? I want to have a full cycle of sleep before I wake up so I chose 2 hours, but is it too long or is it too short?”
-Yerim (via email)

Right off the bat, we can tell you that there is NO perfect sleeping pattern.  Individuals vary so much that what might work for you will not work for your next door neighbor (for instance).  What we can address is the idea of splitting your sleep, and whether that’s a good idea.

There’s actually been a lot of discussion over the last few years about the type of pattern you’re considering, as many scientists believe it’s the natural way people should sleep.  There is a lot of evidence that it was very common hundreds of years ago for people to go to sleep at sundown and wake for a time in the middle of the night.  We wrote about this in an article about sleeping in two segments, published here at SleepBetter in 2012:

Over the years, we tend to forget the way we used to do things, even when those old ways might have been better.  Such is the case with sleeping in two segments, which was quite normal before the invention of electricity freed us from the day/night cycle that had previously ruled our lives.  This “second sleep”, which has been mentioned in literature such as The Canterbury Tales, came after a short period of wakefulness in the middle of the night.  Individuals would go to sleep when the sun went down, and wake sometime around midnight.  They would stay awake for an hour or two before going to sleep again until dawn.

The reason why this makes sense for humans is that, while our sleep patterns used to be tied to the rising and setting of the sun, it stays dark far longer than the amount of sleep a healthy person needs.

The next question is, why don’t we do this anymore? With the invention of electric lights, we’re able to stay awake and be productive well past sundown.  When we finally do sleep, many of us don’t go to bed early enough for even the bare minimum amount of healthy sleep.

To address your idea directly, we wouldn’t expect that you’d see any adverse health effects from this plan.  If you follow the schedule you laid out, you’ll get seven hours of sleep.  We’d recommend you try to push that to seven-and-a-half if possible.  It’s a better total sleep time for most people, and you may find that since you’re not sleeping straight through the night, you may need a little extra.