It's no wonder many of us are sleepy at work

Have trouble nodding off at work?

If so, you're not alone. If you're like a thousand people studied by the National Sleep Foundation, the reason behind your drowsiness may be simple mathematics.

That's because the average person surveyed goes to bed at almost 11 p.m., and wakes up about 5:30 a.m. That's only six hours, 40 minutes a night, or an hour and 20 minutes less than the optimum eight hours a night. Keep up that schedule over a week, and it's no wonder some of us are nodding off at our keyboards.

No big deal if you're working in an office somewhere, but what about the videotape that surfaced of guards sleeping in a "ready room" at the Peach Bottom plant in south-central Pennsylvania?

Or what about the airline pilots who allegedly fell asleep at the controls in a short hop from one island to another in Hawaii?

It's a common problem, common enough that at least two local hospitals have established sleep labs to diagnose problems like sleep apnea, restless leg syndrome and other disorders.

We tend to think the popularity of caffeinated drinks like espresso and energy drinks don't do our sleep habits any good. Neither does Daylight Saving Time, which kicks in Sunday ... but that's another issue.

The Mayo Clinic seems to agree, advising people to avoid nicotine, caffeine and alcohol in the evening among the "10 tips for better sleep" on MayoClinic.com. It takes hours for your body to eliminate caffeine, and although alcohol is often believed to be a sedative, it actually disrupts sleep.

Other tips:

* Go to bed and get up about the same time every day, even on the weekends. That reinforces your body's sleep-wake cycle and helps you fall asleep better at night.

* Don't eat or drink large amounts before bedtime. Eat a light dinner about two hours before sleeping, and avoid spicy or fatty foods if you are prone to heartburn.

* Exercise regularly to fall asleep faster and have more restful sleep. Do it more than three hours before bedtime, however.

* Make your bedroom cool, dark, quiet and comfortable. Use blackout curtains, eye covers, ear plugs, extra blankets, a fan or "white noise" devices to create a good sleeping environment.

* Sleep primarily at night. Daytime naps may steal hours from nightime slumber. Limit daytime sleep to about a half-hour and make it during midafternoon.

* Choose a comfortable mattress and pillow.

* Start a relaxing bedtime routine. Do the same things each night to tell your body it's time to wind down, perhaps including a warm bath, shower, reading a book or listening to soothing music.

* Go to bed when you're tired and turn out the lights. If you don't fall asleep in 15 to 20 minutes, get up and do something else, and go back to bed when you are sleepy.

* Use sleeping pills only as a last resort.

If you're having consistent trouble going to sleep, contact your doctor, who may prescribe a sleep study, a CPAP device, medication or lifestyle changes.