IT SOUNDS STRANGE, THAT TERM "sleep hygiene," but that's the term sleep researchers use when they're talking about good sleep habits. Just as you can have good dental hygiene or bad, so you can have good sleep hygiene or bad. And just as bad dental hygiene can give you cavities, bad sleep hygiene can bring on insomnia, the inability to fall asleep or stay asleep.
Below are some of the rules for good sleep that constitute sleep hygiene. They come from the sleep researchers interviewed for this story and from "No More Sleepless Nights," a thorough, sensible and clear guide to ending insomnia by Peter Hauri, the director of the Mayo Clinic Insomnia Program, and science writer Shirley Linde.
*Limit caffeine. "Caffeine can be a huge problem," says David N. Neubauer, an assistant professor in the department of psychiatry at Johns Hopkins who is associated with the Johns Hopkins Sleep Disorders Center at Francis Scott Key Medical Center. He notes that the effects of this drug -- and caffeine is a drug -- are often underestimated.
Not only can it make it harder for you to fall asleep, it also can make it easier for you to wake up during the night and lower the quality of sleep itself. Most researchers advise avoiding it in the afternoon and evening, but some individuals are so sensitive to its effects that they might try leaving it out entirely. Remember that caffeine is found not only in coffee and tea, but also in many soft drinks, in chocolate and in some drugs such as diet pills and diuretics.
*Limit alcohol. "Alcohol is very interesting because everybody believes it's sedating and it might make you fall asleep," Dr. Neubauer says, but it causes "greater problems later on at night because it promotes much lighter sleep later on at night." A drink at dinner probably won't hurt, say Dr. Hauri and Dr. Linde, but one or more within two hours of bedtime probably will.
*Cut out smoking. Nicotine is a stimulant, Dr. Hauri and Dr. Linde note, and they say a number of studies have associated it with insomnia.
*Avoid napping. Although napping is recommended in some cases, it is almost always ruled out for insomniacs for fear of further disturbing their already disrupted sleep-wake rhythms.
*Don't spend too much time in bed. "People who have insomnia believe they need to spend a huge amount of time [in bed] to achieve every possible potential of sleep they can get," says Dr. Neubauer, citing one patient who would go to bed at 9 p.m. and stay there till 9 a.m. But that kind of extended sleep is scattered and not as refreshing as consolidated sleep, Dr. Neubauer continues, so "sometimes we will also restrict the total amount of time someone stays in bed to consolidate."
If you have been extending your hours in bed in the hope of making up sleep, Dr. Hauri and Dr. Linde recommend cutting back your time in bed to the amount of sleep you used to feel comfortable with before developing insomnia. Others take a more radical approach to consolidating sleep, cutting it to a very short time and then gradually increasing it as the habit of sleeping soundly is re-established. (The case of Loretta Augustin in the accompanying story on sleep disorders is one example, and "No More Sleepless Nights" also includes a discussion of how to consolidate sleep on your own.)
*If you can't sleep, get up and do something else till you feel sleepy. "Do not lie in bed awake for more than 30 minutes," says Thomas E. Hobbins, director of the Maryland Sleep Diagnostic Center in Ruxton. "Get up and do something relaxing." He warns that lying in bed tossing and turning can encourage what is called psychophysiological insomnia, in which you become conditioned to being awake when you should be sleeping. Similarly, don't use your bedroom for an office or for any other activities not associated with sleep, or else you may come to associate being in bed with being awake, not with sleeping.
In some psychophysiological insomnias, Dr. Neubauer says, a specific problem such as a personal crisis will set off a bout of insomnia -- and the insomnia then becomes a habit with a life of its own. "This sort of conditioning occurs very easily in some people," he says. "Some people seem to be more vulnerable to expressing the stresses in their life in their sleep."
*Go to bed and get up at the same time every day. This applies even if you have spent half the night reading because you couldn't sleep in observance of the rule before this one. Otherwise, warn Dr. Hauri and Dr. Linde, "Your body will simply learn to read all night and then sleep all day." If you are an insomniac, they stress, you need to preserve a regular rhythm of sleeping and waking.
*Avoid vigorous exercise within two hours of bedtime, says Dr. Hobbins, because it raises your body temperature: "We sleep best when the body temperature is falling, and we find it hard to sleep when the body temperature is rising." However, overall fitness has been shown to improve sleep, so do exercise -- just not right before bed.
*Don't drink too much liquid or eat a heavy meal before going to bed. If you're dieting, though, note Dr. Hauri and Dr. Linde, a low-cal bedtime snack might help you sleep better, since people who are losing weight are likely to sleep poorly.
*Avoid sleeping pills. If you feel you must use them, use them only sparingly and occasionally for short-term crises or as a very brief break from chronic insomnia, say Dr. Hauri and Dr. Linde. But if you get used to taking them night after night, their efficacy will decrease, and they will cause rebound insomnia when you stop using them.
In addition, prescription sleeping pills often impair performance on the day after they were used, and they can be addictive. They all have side effects, and one of the most popular, Halcion, has been shown to cause short-term amnesia in high doses.
If there is any possibility that you have sleep apnea, absolutely do not take sleeping pills, since they slow respiration, which is already problematic in apneics. Also do not combine them with alcohol, since the combination can be fatal.
Over-the-counter sleep aids usually contain antihistamines, which also become ineffective if used regularly. They also may have side effects.
*If you suspect your insomnia is caused by depression or anxiety, get treatment for that. "Almost half the people reporting insomnia have some mental illness such as depression or an anxiety disorder," says Dr. Susan J. Blumenthal, chief of the behavioral medicine program at the National Institute of Mental Health and clinical professor of psychiatry at Georgetown School of Medicine. "Sleep disturbances are characteristic of many mental illnesses." For dealing with garden-variety tension and anxiety, "No More Sleepless Nights" includes a chapter on bedtime relaxation techniques and one on managing stress.
*Don't worry about your insomnia. Difficult though this may be to believe at 3 a.m. on a sleepless night, write Dr. Hauri and Dr. Linde, you will be able to function tomorrow. If you don't believe it, think of the high achievers who have had the same problem you do: Mark Twain, Sarah Bernhardt, Lewis Carroll, F. Scott Fitzgerald, Proust, Kafka, Kipling and Nietzsche among them. You're in good company.