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Shelby Harris, Psy.D., C.BSM is Director of the Behavioral Sleep Medicine Program at the Sleep-Wake Disorders Center at Montefiore Medical Center and Assistant Professor of Neurology as well as Psychiatry[…]
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In the pre-modern world, circadian rhythms were synched with the rising and setting of the sun, but modern life requires many to adjust their internal clocks to accommodate alternative sleeping habits.

Question: How do circadian rhythms affect our sleep patterns? 

Shelby Harris: So when it comes to circadian rhythms, it’s a clock that’s basically programmed in our body.  So if you think back to times when people lived on farms and we didn’t have electricity.  People went to bed when the sun went down and they woke up when the sun came up.  That’s what our bodies are naturally programmed to do.  However, with all the new stresses in life with electricity, with technology, we tend to override that system and we’ll stay up later and we’ll get up earlier or later, and we use alarm clocks, we use the light.  We haven’t really – it’s harder for us to set those rhythms.  So it’s really important to keep a steady bedtime and wake time to really lock in those rhythms.  

Now circadian rhythms become very interesting and problematic for patients because when you become a teenager, your rhythms actually tend to naturally shift.  So someone who is a child usually goes to bed about 8:00 or 9:00 at night, but then when they have a circadian rhythm shift, it shifts later.  And this is natural.  And they start to go to bed at 11:00, 12:00, 1:00 and they want to sleep later.  So we see this a lot in teens.  And there’s a problem for them when they have to get up and go to school in the morning, they’re very sleepy, yet on the weekends, they’ll sleep 12 hours, they’ll sleep late and then go to bed late and wake up late.  And on vacations, it’s not a problem.  

So we don’t really treat it unless it’s actually a real problem for them in school.  And then some patients actually find that this problem continues into adulthood.  We’re not really sure why it continues, but when they become adults, we usually have to treat it because many people need to get up early to go to work and they can’t be sleeping until 11:00 or 12:00.  So we use treatments like bright light therapy, melatonin, things like that that are very effective.  

And then we have other opposite problems with circadian rhythms that can happen when you – a lot of times with older adults.  They start to go to bed at 6:00, 7:00 at night and they wake up at 2:00 in the morning.  And they’re rhythms actually shift earlier, but sometime it can just kind of miss the mark and shift too much earlier and that’s when we need to treat it with bright light.  

And circadian rhythms come into play with shift work.  So a lot of people who work rotating shifts and they work at night, their bodies are set to want to be awake during the day and sleep at night.  So there are some people who have a lot of trouble adjusting their rhythms and they have trouble working the night shift, they’re sleepy, they’re drowsy driving home.  And that’s when we need to look at as well and really treat it if it’s becoming a problem. 

Question: Is it possible to live nocturnally and get enough sleep? 

Shelby Harris: Yeah, there’s some people who just naturally do it better.  It’s uncommon, but there are some people who just have a delayed circadian rhythm and they just – they sleep better during the day then they do at night.  So they’ve – a lot of those people with delayed sleep phase disorder they start to work in bars, they work some of the late night shifts, they sort of adjust to doing it more and more as time goes on.

Question: What’s the best way to deal with jet lag?

Shelby Harris: All right, so jet lag depends on which direction you’re going and it can be a little complicated, but there are a few different treatments.  So one would be if you’re going somewhere – sorry it’s hard to think about it.  If you’re going somewhere East from here, generally what you want to do is you want to try to have your bed time earlier and earlier so what we’ll do is I’ll have someone adjust for a week or two by going to be 15 minutes earlier and getting up 15 minutes earlier every night.  So that can be a really simple thing.  Honestly, what we use a lot is melatonin.  So we use lower dosages of melatonin, taking it at different times, depending upon where we are traveling and that can really help adjust the body’s rhythm to wherever you are going.  


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