Melatonin, the natural sleep medicine

Melatonin deficiency seems to be a key variable in the incidence of sleep disorders in elderly people and melatonin replacement therapy may prove beneficial.

What if there was a safe and natural medicine that in addition to giving you a deep sleep would provide vivid dreams, eliminate jet lag and also improve your mood? What if it could enhance your immune system, treat a variety of diseases, and even prolong your life span?

Melatonin is now available as a supplement, no prescription needed. Is melatonin this miracle medicine?

A few years ago researchers in Switzerland gave mice melatonin in their drinking water. Another group of mice received plain water. At the start of the study all the mice were about 19 months old (equivalent to 60 years in humans) and healthy.

The researchers were surprised when the mice on melatonin showed such a striking improvement in their health, and most remarkable, lived so much longer! After 5 months on melatonin, astonishing differences in the fur quality and vigor of the two groups became evident. The mean survival time of the melatonin-treat-ed mice was 31 months (96 years in humans) versus 25 months (78 years) in the untreated group!

What is melatonin? "I've heard of it," said a friend of mine when I told her that I was writing a book on melatonin. "That's skin pigment isn't it?"

She was thinking of melanin, the dark color in skin and hair. Since that conversation I've encountered many people who confuse the two words. Melatonin is a natural substance made by the pineal gland, which is located in the brain. Melatonin is a molecule made from the brain chemical serotonin, which is in turn made from tryptophan, an amino acid that we ingest through food. Melatonin helps to set and control the internal clock that governs the natural rhythms of the body. Each night the pineal gland produces melatonin which helps us fall asleep. Research on this substance has been going on since it was discovered in 1958, but it has only been in the last few years that there has been such interest in this chemical. Close to a thousand articles about melatonin were published worldwide in 1994. One reason for this growing interest is that we are realizing that deep sleep is not the only by-product of melatonin. We are learning that is has significant influence on our hormonal, immune, and nervous systems. Research is accumulating about melatonin's role as a powerful antioxidant, its possible anti-aging benefits, and its immune-enhancing properties. It is an effective tool to prevent or cure jet lag, an ideal substance to reset the biological clock in shift workers, and a great medicine for those who have insomnia. Melatonin also may have roles to play in the treatment of prostate enlargement, as an addition to cancer treatment, in lowering cholesterol levels, in influencing reproduction, and more. A delightful bonus is that melatonin can induce vivid dreams.

Is melatonin safe? Whenever researchers want to test the dangers of a substance, they give it to laboratory animals such as mice. They give progressively higher and higher doses of the substance until a lethal dose (LD) is reached where 50% of the test animals die. This level is called the LD 50. Back in 1967, at the National Heart Institute in Bethesda, Maryland, Dr. Barchas and his colleagues gave mice 800 mg per kilogram of body weight of melatonin. The mice exhibited no significant ill effects. The researchers needed to give more to find the LD 50 but they could not concentrate the melatonin any further in the amount of liquid that the mice had to drink. The 800 mg./k. is equivalent to giving an average-sized human over 50000 mg. Most people do well with a nightly dose of less than 5 mg.

Are there any side effects with long-term use? When 300 human subjects were given as much as 6,000 mg. nightly for one month, some of them complained of abdominal discomfort. These high doses did lead to sleeplessness the next day, but only for a few hours. No serious side effects were reported. In a longer-term study using high doses, ovarian function was inhibited when women took 300 mg. nightly for four months. No other side effects were noted. The researchers speculate that high doses of melatonin could be used as an effective oral contraceptive. Low doses are not known to cause these side effects.

The longest user of melatonin that I know is Mark, a 56-year-old psychologist. He tells me, "I first started buying melatonin from overseas in 1991 before it became available in the U.S. I've been using 10 mg. every third night or so for four years and have not noticed any side effects. If I take melatonin every night it loses some of its effectiveness. I don't notice withdrawal or insomnia on the nights that I don't take it. I used to have chronic insomnia. I think melatonin has allowed me to sleep more and better. I think that this deeper sleep is strongly anti-aging since inadequate sleep accelerates aging."

Since melatonin is produced naturally, the body has evolved mechanisms to remove excessive amounts. It is metabolized by the liver and possibly other organs. No reports of any serious side effects have yet been reported in medical literature. None of the 200 individuals in my survey have reported any serious side effects. All the side effects reported have been minor and have quickly disappeared upon discontinuation.

Even though melatonin is an incredibly safe substance for short-term use, and probably very safe for long-term occasional use, it is still important to follow appropriate cautions until more studies are available.

Melatonin should not be used regularly by anyone who is pregnant, lactating, has a serious illness, or is taking medicines without first consulting a physician familiar with its use.

Disturbances in the pattern of sleep are very common in the elderly. Older people usually spend more time in bed but less time asleep. They are more easily disturbed from sleep than the young. They wake up more frequently and have trouble falling back to sleep. Consequences of inadequate sleep are easily predictable: daytime fatigue, napping, and low mood. Age-related changes in sleep are often not related to any medical or psychiatric disorders.

A study was conducted in Israel by Haimov and his associates concerning melatonin levels in the elderly. The study was published in the British Medical Journal in 1994. Haimov found that the quality of sleep in the elderly was proportional to the amount of melatonin secreted by the pineal gland. Elderly patients with insomnia had half the amount of melatonin as younger people. The researchers cautiously concluded, "Melatonin deficiency seems to be a key variable in the incidence of sleep disorders in elderly people and melatonin replacement therapy may prove beneficial."

As you can see from the graph, levels of melatonin progressively decrease as we age. The amount of time we sleep is roughly 16 hours as infants, eight hours in adolescence, seven hours as adults, and less than six house as we go on in geriatric years. Many people who are past middle age report shallower sleep; their circadian rhythm becomes increasingly irregular.

There are factors besides melatonin secretion that impair quality of sleep. Some important ones include decreased physical activity, depression and/or anxiety, illnesses such as heart disease or diabetes, medications that interfere with circadian rhythms, menopause (decreased levels of estrogen), and nocturia (going to the bathroom at night to urinate).

How is melatonin available? Melatonin supplements are currently available in .75 mg., 2 mg., 3 mg., 5 mg., and 10 mg. tablets or capsules. Lozenges are available in 2.5 mg. and 5 mg. Melatonin is not patented, therefore, a number of companies manufacture and distribute it. A wide range of doses works for people. Each person has a unique physiology, therefore, no blanket statements about dosages can be made. Furthermore, the amount of melatonin available in capsules, pills, or lozenges may vary between different products and manufacturers.

When taken on a full stomach, a melatonin pill does not seem to be as consistently effective; perhaps it is not absorbed as well, or it is absorbed too slowly. Taking it with a small meal or on an empty stomach is likely to be more effective. After swallowing a pill, peak levels in the blood are found in about one hour.

Melatonin in the range of .5 mg. to 12 mg. is effective in inducing and maintaining deep sleep in most people. If a person does not respond to a low dose, such as 1 or 2 mg., he or she is likely to respond to higher doses, such as 5 to 10 mg. If there is no response to pills, lozenges can be tried. Lozenges seem to be more consistently effective than pills since they do not need to be absorbed from the stomach. The melatonin directly goes into the bloodstream from absorption through the mouth. However, there are some people who respond weakly even to high doses.

When is the best time to take it? There is a wide variation between people on the best time to take melatonin. Pills are effective for most when taken about half an hour to two hours before bed. Lozenges dissolved in the mouth are effective when taken within 20 minutes to an hour before going to bed. Most people notice a yawn within 30 minutes of dosing. I personally do well with half or even a third of a 2.5 mg. lozenge taken an hour before bedtime. When I put my head on the pillow, I'm out within seconds. I have found lower dose is more effective when taken at least an hour to two before bed while a higher dose can be taken closer to bedtime.

In conclusion, it appears tests with melatonin show a definite help for jet lag, insomnia and mood elevation. In addition it is an important supplement for the immune system.

PHOTO (BLACK & WHITE): Melatonin helps to set and control the internal clock that governs the natural rhythms of the body. Each night the pineal gland produces melatonin which helps us fall asleep.



By Ray Sahelian, M.D.

Ray Sahelian, M.D., author of a recently published book, Melatonin, is a physician certified by the American Board of Family Medicine. He has treated patients with sleep disorders for over ten years. This article is an excerpt from Melatonin. Dr. Sahelian writes health and nutrition articles and frequently appears on radio and television. He is interested in learning about your personal experience with the use of melatonin. Write to Be Happier Press, P.O Box 12619, Marina Del Rey, CA 90295.

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