Melatonin is a hormone secreted by an endocrine gland in the brain called epiphysis. In humans, the main role is to stimulate and regulate the sleep cycle and many biochemical functions through the regulation of the circadian rhythm.
Thanks to the above property, it is also called sleep hormone while is further characterized with anxiolytic properties. Natural sources are cherries, tomatoes, olive oil, wine, beer, grapes, walnuts, almonds, mustard and corn.
Action & properties
Human body has its own internal clock that regulates the hours we wake up or sleep. This biological clock (circadian rhythm) is adjusted by the action of certain hormones including melatonin.
In the biosynthesis of hormone in the epiphysis, it is also involved, as structural element, the essential amino acid tryptophan and serotonin. Melatonin secretion gradualy starts when is getting dark because darkness triggers its production. The peak is late at night and then gradually decreases until the first morning hours. It is a light-sensitive hormone. The secretion of melatonin induces a series of chemical changes in the body thereby causing drowsiness. Specifically, it reduces body temperature, blood pressure and stimulates the central nervous system, gradually promoting relaxation, rest and sleep.
The melatonin secretion varies between age groups. Teens can sleep later and wake up later while the elderly presents a dramatic decrease of melatonin secretion. General factors – conditions that can affect the production of melatonin and affect the quality of sleep are:
- Circular working hours
- Degeneration of the central nervous system
- Diabetic neuropathy
- Certain cancer types
- Alzheimer’s disease
- Certain drugs (beta-blockers, antidepressants, nonsteroidal anti-inflammatory)
Insomnia & jet lag
Adequate sleep is essential for the overall health of the organization. Many studies have shown that taking melatonin supplementation helps significantly to enhance sleep quality and duration. People who benefit from melatonin supplementation are those who suffer from insomnia and sleep disorders (nocturnal awakenings) either due to lifestyle, such as stressful events, or due to normal aging.
Moreover, many studies have shown that people who have night or cyclic shifts in work can improve the duration and quality of sleep even during the day. Similarly, it helps both prevention and reduction of jet lag, which is observed in people who make long flights in different time zones, and helps body clock to adapt faster to the time changes.
Antioxidant and anti-aging effects
Melatonin has antioxidant and anti-aging properties, offers cardiovascular protection while it promotes the production of antioxidant enzymes.
Due to the chemical structure of the molecule, it can easily penetrate in cells, especially in brain and to cross the blood-brain barrier, a property that no other antioxidant molecule has. Doing so, it protects the cells and nerves in the brain from degeneration due to oxidative stress.
Alzheimer’s Disease & Memory
Melatonin has also a key role in Alzheimer’s disease and dementia as it appears to have neuroprotective properties.
Specifically it has been shown that people with Alzheimer’s disease suffer from sleep disorders and confusion. By taking melatonin supplements they can improve their memory and/or delay the decline of cognitive function.
Depression and mental illness
Several studies suggest the involvement of melatonin in various psychopathological conditions such as depression, bipolar disorder, etc.. These mental diseases are characterized by deregulation of circadian rhythm. Taking melatonin supplements seem to help treat seasonal depression and emotional disorders.
Migraines & Headaches
Melatin supplementation also seems to help prevent headaches and migraines or even reduce tinnitus.
As one of the physiological effects of melatonin secretion is the reduction of blood pressure, it has been found that supplementation can lead to a reduction of nocturnal pressure without altering heart rate, thus contributing to better arterial pressure control.
Obesity and metabolic syndrome
References demonstrate the role of melatonin even in weight management. It seems that the hormonal role extends to body’s thermogenesis ability.
Dosage forms & supplements
Usually the doses are between 0.3-10 mg per day. Commercially supplements exist in tablets, capsules, sublingual lozenges and sprays. Immediate or fast release is usually achieved with sublingual tablets and sprays. In each case, the peak levels of melatonin in the blood serum is achieved within about 1 -2 hours.
Depending on the formulation, it is usually taken 30-60 minutes before bedtime. In many supplements it is combined with passionflower, vitamins of b complex, amino acids and other sedative herbs such as chamomile and hops.
Side effects & interactions
There have been reported mild gastrointestinal disturbances such as nausea, excessive sleepiness in the morning, irritability, hypothermia and even vivid dreams.
The use should be avoided by children, pregnant or lactating women, people taking antidepressants, beta-blockers to control blood pressure, hypnotics, anticoagulants, contraceptives and antidiabetic drugs. Furthermore, avoid taking melatonin supplements along with alcohol.
In Vita4you you can find a wide variety of melatonin supplements.