03/18/2010 05:12 am ET | Updated Nov 17, 2011

Caffeine Adversely Affects Sleep Cycle For Many

Coffee is most everyone's number one choice for a pick-up-me. Have to work late? Coffee. Couldn't get a full night's sleep? Coffee. Need a jolt of energy to stay focused and alert? Coffee.

You can count on coffee, or really anything with caffeine in it, to get you through it. But watch out if you're among those who work at night and sleep during the day: there's new evidence that coffee can really tie a knot in your attempts to get some sleep when you need it most.

According to a recent study led by a Canadian researcher in Montreal, caffeine interferes with sleep and this effect worsens with age. For shift workers, who need to sleep during the day, caffeine can really antagonize sleep.

Okay, so that may not sound like anything too shocking and new. We all know caffeine is a stimulant that can disrupt sleep when taken too close to bedtime. But what this study pointed out is the fact caffeine can have unintended consequences. Many people who enjoy coffee claim that they can sleep like a baby after drinking coffee, and that it doesn't affect them as significantly as others.

That's not necessarily true. If you put these self-proclaimed caffeine warriors into sleep labs, you'll find their sleep fragmented. They don't get high-quality sleep even though they think they do.

This is lesson for all, not just shift workers who are in a unique situation. Don't fool yourself into believing you're superhuman and that caffeine doesn't work on you. Nice try. While it's true that everyone's tolerance and metabolism for caffeine may be slightly different, that doesn't mean some of us get a free pass on its negative consequences to sound sleep.  So whether you're a shift worker or have a day job, heed the following:

  • Avoid caffeine within eight hours, if possible, of your bedtime (that's 2 pm for most of us).
  • Watch out for caffeine lurking in other products, like headache medicine, chocolate, and energy drinks.
  • Think about going a little lighter on the caffeine if you're older than 40. At appears that the older you are, the more caffeine will interrupt your sleep.

Besides, there's no greater solution to fatigue and energy loss than a good night's sleep. Even naps have already been proven to be better than a cup of joe. There's a time and place for caffeine, so just mind it. 

Sweet Dreams,

Michael J. Breus, PhD

The Sleep Doctor™

This article on sleep and caffeine is also available at Dr. Breus's official blog, The Insomnia Blog.