Had Any Good Sleep Lately?
Melatonin may help you sleep better—
which, if you’re typical, you probably need
By Will Block
It is not true that some people need less
sleep than others. They simply sleep faster.
— Peter De Vries
ow "fast" do you sleep? Are you a speed demon, like the phenomenally productive Thomas Edison, who needed only a couple of hours of sleep each night, or do you sleep in the slow lane, needing a good 10 hours or so in order not to be a zombie during the day? Albert Einstein was a notoriously long, slow sleeper, but he sure made good use of his waking hours. In any case, let’s not kid ourselves that if we emulate either Edison or Einstein, we’ll turn into geniuses. We’re all different, and there is no "right" amount of sleep except that which meets our own body’s needs.
But what about the quality of your sleep? Do you conk out as soon as you hit the sheets and lie there like a log until morning, so oblivious to the world that a whole tree could fall on your roof without waking you? Or do you sleep lightly and fitfully, waking up whenever the dog rolls over (and the dog sleeps in the kitchen)? Or are you perhaps an insomniac, lying awake half the night, thinking dark thoughts about … whatever?
Sleep Needs Change with Age
Chances are it’s been a long time since you’ve slept like the proverbial baby. As we grow older, many things change (write that down!), including both our need for sleep and our ability to get the sleep we need. Our metabolisms change, which means that our energy demands and energy outputs change, and with them, our need for sleep to restore a healthy balance between the two sides of the energy equation.
The restorative power of sleep is as vital to life, ultimately, as food and water. (Some people can push themselves to go for several days without sleep; the record is an astounding 11 days.) Paradoxically, though, sleep is not the completely zonked-out condition of rest that it appears to be—at least not in the brain, which is the body’s biggest single consumer of metabolic energy, through cellular respiration.
The brain, as we’ve known for half a century, is very active during sleep, especially during REM (rapid eye movement) sleep, when we’re dreaming. In all, REM episodes (of which there are typically about four or five nightly) account for about 20–25% of the sleep cycle, or about 2 hours worth in a typical 8-hour stretch. Thus, if you live to be 100, say, you will have spent roughly 73,000 hours—8.3 years!—dreaming.
Melatonin Orchestrates Our Sleep Pattern
One subtle but important aspect of brain activity takes place, 24/7, in the pineal gland, a pea-sized object deep within the brain. This gland produces and secretes the sleep hormone, melatonin (whose precursor is the neurotransmitter serotonin), in a cyclic pattern. Heres how it works: during the day, bright light entering our eyes sends signals via the optic nerve to the visual cortex, resulting in the sensation of vision—you knew that. But signals are also sent to a cluster of cells in the anterior hypothalamus called the suprachiasmatic nucleus (SCN). Popularly known as the biological clock, the SCN is our circadian pacemaker, regulating bodily functions that follow the cycle of day and night.
One of these cyclic functions, of course, is sleep. During the day, the SCN signals the pineal gland to inhibit the synthesis of melatonin. When night falls and light stimuli to the SCN diminish, however, the signal (delivered by the neurotransmitter noradrenaline) is reversed: “OK, pineal gland, time to crank up the melatonin.” When that happens, we become sleepy, and nature takes her course—unless, of course, we resist because we have too many things we have to do or want to do, or because we’re too agitated or worried or whatever to fall asleep.
We’re a Chronically Sleep-Deprived Society
Interference with the natural sleep pattern that evolution built into our genes has become a way of life in our artificially lit, stimulus-rich, high-pressure environment. That’s not good. It leads to chronic sleep deprivation, a pervasive malady in America, and this, in turn, leads to a host of undesirable consequences: fatigue, irritability, depression, impaired reflexes and concentration and judgment, poor job performance, poor family relations, poor sex life (see the sidebar), poor health, and increased accidents. As a consequence of some of these factors, sleep deprivation even leads to premature death. Shift work exacerbates most of the problems and is increasingly viewed by public health authorities as a serious threat to the well-being and the very lives of the workers in question.
Are You Too Sleepy for Sex?
Question: What do insomniac agnostic dyslexics do? Answer: They lie awake all night wondering if there is a Dog. Well, let’s hope that you don’t fall into any of those categories and that you have better things to do in bed. Like sleep. Or have sex. But wait a minute—what if you’re too sleepy to have sex? And not because you’re exhausted from a long, hard day of work at the office or at home, but simply because you don’t get enough sleep on a regular basis to maintain a decent energy level. (Or an indecent energy level, if that’s how you like to look at it.)
According to a new National Sleep Foundation (NSF) survey of 1506 randomly selected American adults, nearly one-fourth of adults who live with a spouse or partner of some kind have sex less often or have lost interest in sex because they’re too sleepy. That’s a lot of good sex going to waste! Furthermore, a large majority (77%) of “partnered adults” report that their partner has a sleep-related problem, the most common of which is snoring. That’s no joking matter: the sleep problems of one’s bed partner cause an average loss of 49 minutes of sleep a night, or about 300 hours a year! So their sleep problem becomes your sleep problem as well, and it can have a terrible effect on the relationship.
Although the NSF recommends that adults get between 7 and 9 hours of sleep nightly, American adults average only 6.9 hours. Three-quarters of them admit to having frequent symptoms of a sleep problem, such as drowsiness at work or behind the wheel of a car (yikes!), but when asked if they thought they actually had a sleep problem, the same percentage said no. So there are an awful lot of sleepy people stumbling around in a state of denial, endangering themselves and everyone else on the road.
The survey also revealed the epidemic of obesity in America: based on body mass index data, 64% of adults are overweight or obese, conditions that can dramatically impair one’s ability to sleep well. Furthermore, adults who had at least one common medical condition, such as hypertension, arthritis, heartburn, or depression, reported significantly poorer sleep than those who did not, and they were found to be at much higher risk of serious sleep disorders, such as insomnia, sleep apnea, and restless legs syndrome. It pays to stay healthy and, in any case, to get as much sleep as your body needs.
- Sleep in America poll, National Sleep Foundation, 2005. Results can be seen at www.sleepfoundation.org.
It’s bad enough that we do battle, so to speak, with melatonin’s efforts to lull us into dreamland when night falls, but this situation is aggravated by an all too familiar factor: aging, which results in a gradual decline in melatonin synthesis. The evolutionary processes that gave us the biochemical mechanism for sleeping regularly and soundly never prepared us for living as long as we now do. Countless bodily mechanisms seem to be governed by internal clocks of their own, which say, in effect, “This person isn’t going to live much beyond 30 or 40, so you can start slacking off around then.”
Arrggh! It’s enough to make you … turn to supplements for help—especially if you suffer from insomnia.* Melatonin has long been used as an aid for sleep disorders (it must be taken at night, of course, unless you want to feel extra sleepy during the day); it’s particularly helpful for elderly people with insomnia, who have significantly lower levels of melatonin than age-matched people who do not have insomnia. The amounts used usually range from 0.1 to 5 mg daily; although 2 to 3 mg is typical, studies have shown that submilligram levels are probably adequate and perhaps optimal. Melatonin’s effect generally kicks in about 30 minutes after ingestion and lasts for at least an hour; its half-life in the circulation is about 35 to 50 minutes, so by morning, it’s virtually gone.
What’s the Real Story on Melatonin?
Dozens of clinical trials have been conducted on the use of melatonin for sleep enhancement, but they’ve given widely varying results, partly because they represent a dizzying assortment of methods and protocols. For example, they differ in the types of subjects chosen—young or old, healthy or sick, sane or insane, cogent or demented, and, rather importantly, normal sleepers or insomniacs. They also differ in the location used for testing (home or laboratory), the time of day (daytime or nighttime), and the duration (from 1 day to 2 months).
Not to mention the different techniques used for measuring sleep parameters (high-tech and objective vs. low-tech and subjective) and the different designs of the trial to begin with: randomized or not, placebo-controlled or not, double-blinded or not, and parallel or crossover (the manner in which treatment and placebo groups are compared). And let’s not forget the variability in the melatonin itself—different amounts administered on different schedules, using material from different sources, some of them reputable and reliable in terms of purity and quantitative accuracy, and some not.
Good grief! Trying to make sense of all that is like trying to evaluate the performance characteristics of a “standard” automobile based on a hodge-podge of vehicles, from beat-up old Fords to shiny new Ferraris, with some Hummers, go-carts, dragsters, off-roaders, and junkyard rejects thrown in to make it more challenging.
MIT Researchers Try to Find Out
But somebody has to try, now and then, to extract useful information from the welter of stuff that gets published in scientific journals (many of which, frankly, don’t deserve to be called that).* The best way to do this is by meta-analysis, a rigorous examination, by authorities in the field, of the pooled results of existing studies—but only the good ones that are worthy of serious consideration.
A group of researchers at MIT recently undertook a meta-analysis of melatonin studies to try to make sense of them. Of the 54 studies they considered initially, they wound up validating 17 (representing a total of 284 test subjects) for the meta-analysis. They rejected the remaining 37 for a variety of reasons having to do mainly with poor experimental design, poor execution, inadequate reporting of the results, or the use of children as subjects.
Melatonin is particularly helpful for
elderly people with insomnia, who
have lower levels than age-matched
people who do not have insomnia.
Melatonin Produces Modest but Significant Gains
The researchers selected the three most frequently recorded experimental outcomes on which to base their analysis: (1) sleep-onset latency (the time between lights out and the onset of verifiable sleep), (2) sleep efficiency (the ratio of total sleep time to total time in bed, expressed as a percentage), and (3) total sleep duration. Then it was data-crunching time. When the researchers woke up (just kidding), they found that melatonin treatment had produced the following results, on average:
- Sleep-onset latency was reduced by 4.0 minutes. (The normal range without sleep aids is about 15–20 minutes, and a value of 30 minutes or more is regarded as a symptom of insomnia.)
- Sleep efficiency was increased by 2.2%. (Normal sleep efficiency is about 90–95%.)
- Total sleep duration was increased by 12.8 minutes (that’s 2.7% of 8 hours).
It’s noteworthy that 15 of the 17 studies in the meta-analysis involved subjects who were generally healthy, with no known relevant medical conditions other than insomnia (the other two studies involved patients with schizophrenia or Alzheimer’s disease). When the same analysis was repeated on just these 15 studies, the results were similar: sleep onset latency was reduced by 3.9 minutes, sleep efficiency was increased by 3.1%, and total sleep duration was increased by 13.7 minutes.
All in all, the benefits were modest but significant. The authors stated,
The present meta-analysis implies that exogenous [from outside the body] melatonin might have some use in treating insomnia, particularly that associated in aged individuals with nocturnal melatonin deficiency or with an abnormal pattern of melatonin secretion.
How to Be Happier and Healthier
If you value your health and the health of those around you, you owe it to yourself—and to them—to try to get plenty of sleep so that you can be at your best when you’re awake, even if you’re not exactly another Edison or Einstein. People who sleep well are, in general, happier and healthier than those who don’t. It’s Mother Nature’s way of rewarding you for abiding by her rules and letting melatonin do its job. And if you’re a little short on the melatonin because of your age … no problem—it’s always available as a handy nutritional supplement.*
- Dew MA et al. Healthy older adults’ sleep predicts all-cause mortality at 4 to 19 years of follow-up. Psychosom Med 2003;65:63-73.
- Haimov N, Lavie P, Laudon M, Herer P, Vigder C, Zisapel N. Melatonin replacement therapy of elderly insomniacs. Sleep 1995;18(7):598-603.
- Zhdanova IV, Wurtman RJ, Regan MM, Taylor JA, Shi JP, Leclair OU. Melatonin treatment for age-related insomnia. J Clin Endocrinol Metab 2001;86(10):4727-30.
- PDR for Nutritional Supplements. Medical Economics Co., Montvale, NJ, 2001.
- Brzezinski A, Vangel MG, Wurtman RJ, Norrie G, Zhdanova I, Ben-Shushan A, Ford I. Effects of exogenous melatonin on sleep: a meta-analysis. Sleep Med Rev 2005;9:41-50.
Will Block is the publisher and editorial director of Life Enhancement magazine.