Melatonin is a hormone and neurotransmitter that is produced naturally in the pineal gland from the amino acid tryptophan. This is done in a step-wise process in which tryptophan is converted into 5-hydroxy tryptophan (5-HTP) which is converted to serotonin and then to melatonin. It happens after some time in the dark. Between the 2 a.m. and 3 a.m. is the body's melatonin production peaks. However, there is an immediate conversion of melatonin to serotonin in the brain, if the eye gets a certain amount of light - for example, if you turn on the light at night to go to the bathroom. It takes some time after the light has been turned off before the brain's melatonin level is returned to normal.

Melatonin regulates the body's circadian rhythm, which is why supplementation can time-shift "the brain's internal clock."

Melatonin induces drowsiness

Fatigue is your body’s way of expressing that it needs to rest. Technically, you can experience fatigue any time of the day, but the normal thing is to feel tired late in the evening. This is no coincidence. When night falls, your body secretes a hormone called melatonin. Produced in the brain in a small pea-sized gland called the “pineal gland”, melatonin induces a sense of drowsiness that makes you feel like settling down for the night. This pattern repeats itself on a daily basis.

Usually sleepers undergo five sleep stages 1, 2, 3, 4 and REM (Rapid Eye Movements). These stages are cyclic, beginning from stage 1 to REM, and then again with phase 1. A complete sleep cycle takes an average of 90 to 110 minutes. The night's first sleep cycle has a relatively short REM period and a longer period of deep sleep, but later that night the REM sleep is extended and the deep sleep period is shortened.

Stage 1 is light sleep where you drift into and out of sleep and easily can be awakened. At this stage, the eyes move slowly and muscle activity slows. At this stage, many people experience sudden muscle contractions following a sense of falling.

Stage 2 Here the rapid eye movements stops. The brain waves become slower and are only occasional interrupted by rapid brain waves.

Melatonin, a natural substance that gets produced in the human brain at night, is now available over-the-counter. This is great news to people who suffer from recurrent insomnia or individuals who do cross-Atlantic travelling all the time and tend to get jetlag.

People who routinely have problems falling asleep at night may find tremendous relief in melatonin, a natural “sleep hormone” that is now available in tablet form over-the-counter. The substance installs a restful and natural sleep, allowing you to wake up feeling fresh and invigorated. Unlike conventional sleeping drugs that can be habit-forming and tend to make you feel drowsy, melatonin stimulates the body’s natural sleep pattern and actually succeeds in making you sleep solidly through the entire night.

What is melatonin?

Melatonin is a hormone which the human body produces at nightfall. It is secreted naturally by the pineal gland (which is located at the center of the brain) in response to nightfall.

What is melatonin’s role?

Melatonin regulates the body’s 24-hour clock (also known as the circadian rhythm). The pineal gland secretes melatonin in response to darkness in order to induce drowsiness, which causes us humans to sleep. Besides functioning as a natural “sleep inducer”, melatonin functions as an antioxidant that repairs cellular damage during our sleep.

An alarming number of people rely on sleeping medicine in order to get some shuteye at night, but there is a better - and completely natural - way of dosing off. Melatonin, a hormone that is produced in the brain at night, can help you go to sleep whenever you want to.

At night, when it is dark out, most of us start feeling tired. We climb into bed and have absolutely no trouble falling asleep. Not everyone is that lucky, however, and surprisingly many people rely on sleeping medicine, but these drugs only make you drowsy and are not really able to produce a restful sleep. A new and better alternative has come up, though: a natural hormone called melatonin. The substance, which is nature's own sleeping remedy, gets produced in the brain in response to nightfall. Basically, what it does is to regulate our 24-hour periodicity - the so-called circadian rhythm (see box).