The secretion of melatonin follows a daily rhythm governed by the body's master clock. This clock is located in the brain and is synchronized by regular exposure to the 24-hour cycle of darkness and light. Melatonin secretion may serve as a biological time cue. Although its natural secretion in the body peaks at night, melatonin does not control sleep. If it did, night workers would not be able to sleep in the daytime when melatonin levels are low.

Healthy young and middle-aged adults usually secrete about 5 to 25 micrograms of melatonin each night - at least 80 times less than is in the commonly sold 2 milligram (mg.) tablet or capsule. The amount of melatonin the body secretes tends to decline with age, a possible link with an age-related rise in difficulty sleeping. See similar questions...

Melatonin has a rapid, mild sleepiness-inducing effect. Because of this trait, properly timed melatonin supplements may help people adapt to changes in sleep-wake schedules, as may occur after jet travel across many time zones or in shift work. The effectiveness of melatonin for relieving insomnia is uncertain. Many concerns remain about melatonin's safety, especially for long-term use. See similar questions...

Melatonin regulates biological rhythms such as the sleep/wake cycle. It also acts as an antioxidant, protecting cells from damage caused by free radicals, the toxic by-products of normal cell metabolism.* Melatonin is one of the most useful and versatile substances produced in the body. See similar questions...

Melatonin's long-term safety has not been established. There are growing concerns about the possibility of damage to the retina of the eye associated with melatonin use. you work as a pilot, trucker, railroader, or in another occupation in which a lack of alertness on the job could endanger yourself or others Because of concerns about transmission of viruses through animal products, melatonin derived from cow pineal glands should not be taken. See similar questions...

Acute: Minor. About eight out of 100 people taking 5 mg. melatonin or less per day to prevent jet lag feel sleepy in the daytime. Fewer than two out of 100 on this dose suffer a headache, feelings of fuzziness or giddiness, or nausea. In research studies using doses up to 300 mg. daily, the side effects occurring most frequently were diarrhea, abdominal pain and headaches. See similar questions...

Melatonin is sold as a dietary supplement, not as a drug, often in health food and other grocery stores and some drug stores. Because it is not labeled as a drug, Food and Drug Administration (FDA) regulations that apply to medications sold in the United States do not apply to melatonin. The FDA does not require manufacturers of melatonin to demonstrate that their product is safe and effective nor to monitor its safety and efficacy, as is the case for drugs. See similar questions...

HTP may prove to be better than melatonin. Several clinical studies have shown 5-HTP to produce good results in promoting and maintaining sleep in normal subjects as well as those experiencing insomnia . One of the key benefits with 5-HTP in the treatment of insomnia is its ability to increase sleep quality. See similar questions...

Any product which is offered in liquid form will be more quickly available for your body, because it is more quickly absorbed. Because the effects of Liquid Melatonin vary among individuals, the dosage is easily adjustable. See similar questions...

No. You should normally wake up well refreshed and full of energy. If you wake up feeling a little tired you should reduce your dosage until you wake up feeling well refreshed. See similar questions...

As we age our bodies produce less and less melatonin so that by age 45, most people produce less than half the melatonin they produced at age 20. This reduction in melatonin can make restful sleep more difficult to achieve. Dietary supplementation with MELATONEX can help to restore the melatonin we need for restful, natural sleep.* See similar questions...

For your health and safety the melatonin in MELATONEX is produced in a laboratory, eliminating the risk of contamination associated with animal sources. See similar questions...

Yes. Several thousand people have taken melatonin in carefully monitored clinical studies, some in daily doses of several thousand grams or more. Without exception, these studies have shown no toxic effects and leading experts in the field agree that melatonin is remarkably safe. See similar questions...

People who have the following conditions should always check with their physicians before taking melatonin: persons who are pregnant or lactating, or have an autoimmune, seizure or endocrine disorder. See similar questions...

Review #1 - ME/CFS Sufferer (inc. general info) : Melatonin review / Melatonin suggested use ~ "Melatonin is your natural 'sleep hormone' that your brain produces when it gets dark. PVFS/CFS/ME and FMS sufferers have been shown to have abnormal levels of melatonin. Research suggests that ME/CFS..." More... Review #1 - ME/CFS Sufferer: Chronic Fatigue Diet ~ "This book really woke me up to the importance of what you eat when you have CFS . A good CFS diet is crucial..." More. See similar questions...

No studies of humans support this notion. In one group of animal studies, the pineal glands of young mice were transplanted into old mice, and vice versa. The old mice allegedly lived longer. The young mice allegedly died sooner. Some strains of mice used in these studies, however, have a genetic defect that keeps them from producing melatonin. The alleged benefits therefore could not have come from melatonin. See similar questions...

While some positive evidence comes from animal studies, more work must be done to confirm and extend these findings. It is a big leap from mice to humans. See similar questions...

It is important in regulating sleep, and may play a role in maintaining circadian rhythm, the body's natural time clock. Natural melatonin production decreases with age, and the decrease is associated with some sleep disorders, particularly in the elderly. The use of melatonin supplements became popular in the mid-1990s as a way of treating insomnia. (Adapted from Answers.com) See similar questions...

Based on available studies and clinical use, melatonin is generally regarded as safe in recommended doses for short-term use. Available trials report that overall adverse effects are not significantly more common with melatonin than placebo." (U.S. National Institutes of Health) In the most extensive clinical trial to date a high dose of 75 milligrams of melatonin per day was given to 1400 women in the Netherlands for up to four years with no ill effects." (Newsweek, 6 Nov. 1995, 60-63.) See similar questions...