Does a glass of warm milk before bedtime really contain enough of the amino acid tryptophan to help you fall asleep? Yes.
A number of studies suggest that drinking warm milk before retiring for the night not only can shorten the amount of time it takes to fall asleep but also make the sleep more restful.
Not only the warm milk, but the act of warming the milk, of taking care of yourself, in a quiet setting also helps. It could be an "auto-suggestive technique" akin to "low-level hypnotherapy" that proves calming enough to bring on sleep.
Whatever the mechanism, for the estimated 10 to 17 percent of the adult U.S. population with insomnia, warm milk may be worth considering. Add in the millions of Americans who choose to burn the candle at both ends by averaging no more than seven hours of sleep a night when they should be getting at least eight, and you've got the majority of the population in a sleep-deprivation epidemic.
It's serious. Some $100 billion is lost yearly in productivity, sick leave, medical expenses, and property damage due to lack of sleep, according to the National Sleep Foundation.
The National Highway Traffic Safety Administration estimates that more than 100,000 crashes a year are caused by drivers nodding off behind the wheel. Thousands die in these accidents.
Admittedly, a glass of warm milk isn't going to solve the nation's sleep problem. But paying attention to what you consume—and when—can benefit the quality and quantity of your slumber. Here are several other food-related "sleep hygiene" steps to consider.
- Try chamomile tea
Chamomile is considered to have a mild sedative effect.
- Don't have a nightcap
Alcohol may help some people fall asleep, but it interferes with substances in the brain that allow for continuous sleep. The result is repeated waking (or partial waking) through the night, leading to fewer hours of truly deep, restful sleep. (A drink at dinner is okay, but avoid drinking between dinner and bedtime.)
- Don't eat a large meal too close to bedtime
Typically, it takes about four hours after eating for the stomach to empty its contents. But the acid secreted to break down those contents can last up to seven hours. That's a particular problem for those with acid reflux and the ensuing heartburn and other gastric distress it causes; such discomfort can keep people awake.
Eating too close to bedtime could also cause spontaneous arousal, or lightening of one's sleep, for reasons that don't appear to have anything to do with reflux.
- But don't go to bed too hungry, either
Going many hours without food causes the release of a hormone called glucagon, which sends a signal to let more sugar into the bloodstream. But glucagon has side effects that are thought to be similar to those of adrenaline, the fight-or-flight hormone that creates a state of agitation.
People with anxiety disorders might be especially sensitive to that effect and thus might want to be especially conscientious about not going to bed with a rumbling stomach. (Maybe that's the reason a glass of warm milk induces sleepiness in some people it staves off hunger.)
- For restless leg syndrome, talk to your doctor about taking supplements of iron or vitamin E
Up to five percent of the population has restless leg syndrome, which worsens when the body is inactive and thereby causes a very strong urge to move the legs and interrupt sleep. Some sufferers have an iron deficiency and see their symptoms diminish with iron supplementation. If you have these symptoms, have your doctor check your iron status.
- Be aware of caffeine and other drug ingredients
You already know that a cup of coffee has about 85 milligrams of caffeine—enough to interfere with a good night's sleep, since the powerful drug can exert a stimulant effect for up to seven hours. But were you aware that some over-the-counter pain medications, if taken several times a day, contribute as much caffeine as several cups of coffee?
Ingredients in cold medicines such as ephedrine, pseudoephedrine, and phenylpropanolamine, also act as stimulants—which is why some drugs taken to get a better night's sleep during a cold or flu contribute to sleeplessness after a few nights
Prescription drugs can take their toll on sleep, too.
If you are taking a drug on a regular basis and have difficulty sleeping, ask your physician if the drug could be at least partly responsible—and whether the dosage or the timing of the drug taking could be modified.