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Matthew J. Edlund M.D.

Why Can't I Sleep? Six Common Reasons You Can Fix

Can I ever feel fully alert again?

You're exhausted. You can't wait to sleep. Your head hits the pillow and, then: frustration. You open your eyes in the middle of the night and find yourself staring at the clock, which coldly stares back. And you just read that people who sleep less than seven hours die younger and last night you got only ...

Cool it. Americans have gotten so used to chronic sleep deprivation that most of us no longer even know what it feels like to be fully alert, awake, and aware.

You probably already know many of the common causes for not sleeping, from shift work to depression, but here are a few you may not have heard about — and which can more easily be fixed:

1. Clockwatching. You wake up, then look at the clock to know how much time you have left to sleep, right?

Wrong. Time rules life, particularly the important 24 hour rhythms that make heart attacks five times more common on Monday morning and set up early morning disasters like Three Mile Island and Chernobyl (see my "Body Clock Advantage" for how to use those clocks profitably.) So don't be surprised if you wake every morning at 3 AM, because looking at the clock entrains those 24-hour rhythms.

2. Caffeine's long reach. Harvard professor Quentin Regestein liked to explain how two young women diagnosed with narcolepsy lost their uncontrollable daytime sleepiness once they gave up their two cups of morning coffee. Wonderful as caffeine is, it can last a long time. The average "half-life" of caffeine is around five hours: After the first big hit distributed to all tissues your body gets rid of half the stuff in five hours, three-quarters in 10 hours, and seven-eighths in 15 hours — which means caffeine remains in your blood when you're trying to sleep.

And plenty of us knock off caffeine much more slowly, which means lots is there when it's time for shuteye. So when your teenager gulps two energy drinks to rev up for afternoon soccer, don't be shocked when she says she can't sleep.

3. Turning sleep into a job. It's eleven PM, you have an important early morning meeting, you've got to wake at 5:30 to shower, put on make-up, rouse the kids and make their lunches so you better sleep every minute.

Except often you don't. Worrying about sleep, thinking about sleep, is a great way to not sleep. Called psychophysiologic insomnia, it's a particular nightmare for working professionals. And consider your kid whose cell phone lays next to her head all night wondering who will call with an absolutely amazing story?

4. The amazing changing ways of booze. Lots of people use alcohol as their knockout drop, yet few know that alcohol thes sleeping pill will cause 15-25 more arousals that night. Most won't remember these brain arousals, because you usually have to be up 6-8 minutes to remember being awake. Plus it's the rare late night imbiber who knows long term alcohol use may provoke severe insomnia, or that alcohol's effects on the brain are 2-3 times greater at midnight than 6 PM, a cause of major night-time mortality.

5. Inadequately treated sleep disorders. For the millions of sleep apneics out there, it's time to wake up to the problem of insomnia. Studies presented at the recent sleep meeting in San Antonio demonstrated half or more of people with sleep apnea are also insomniac.
Why? Because CPAP machines and dental devices often do not solve sleep apnea let alone other sleep problems, nor cut the system wide inflammation sleep apnea causes.

6. Smoking. Sorry, smokers, but most of you undergo nicotine withdrawal every time you sleep. Your brain probably wakes up an extra 15-to-20 times.

What to Do?

Simple: Use your body the way it's built. Hide clocks behind a book; limit caffeine use to early-to-mid morning; rest before sleep, and avoid late-night alcohol. Quitting smoking is much tougher, but sometimes knowing what tobacco does to sleep gives that last necessary incentive to stop the expensive weed.

Fortunately sleep is a part of rest that's all about conditioning - the little behaviors that make falling asleep restful and fun, as sleep reworks and rewires your brain. Even 20-30 minutes of walking leads to new brain cell growth at night.

Remember that acorn on the forest floor? That acorn can generate a grand oak tree. That power of regeneration is what rest does for your body. Much of the insides of your cells are replaced in hours to days. The proteins pumping your heart that lets you read this sentence are gone in 60-to-90 minutes. That's pretty fast.

It's time to give rest a chance.


About the Author

Matthew Edlund, M.D., researches rest, sleep, performance, and public health. He is the author of Healthy Without Health Insurance and The Power of Rest.