Melatonin is a hormone produced by the pineal gland located deep in the center of the brain. It is produced in response to darkness and it’s production is inhibited by bright light. Melatonin is produced from serotonin which is produced from the amino acid tryptophan. Melatonin is literally responsible for the sleep/awake cycle of the body. These factors come into play in the case of night workers and shift workers as well as travelers who experience jet lag. As melatonin production peaks in adolescence and declines with age, it is one of the factors that contributes to less quantity and quality of deep sleep in aged adults. It has also been noted that melatonin is lower in patients with coronary artery disease.
A diet high in carbohydrates inhibits melatonin secretion by shifting the amino acid balance. The B vitamins are necessary to convert melatonin from tryptophan and should be supplemented during melatonin therapy. Other factors which decrease melatonin secretion are:
- Cardiac and blood pressure medicines such as beta blockers, calcium channel blockers and alpha
- Adrenergic blockers
- Ibuprofen and aspirin
- Electromagnetic fields
There are factors which increase melatonin production:
BENEFITS OF MELATONIN
The sleep produced by melatonin is characterized by:
- Improved sleep pattern
- Improved sleep quality and less trouble going back to sleep after waking at night
- Increased slow wave sleep with consequent increase in growth hormone production
- Dreams are usually vivid and many people report dreaming as a pleasure that they have not experienced since a younger age.
- Since melatonin is brought on by darkness and decreased by light it may reset the sleep cycle as in jetlag with the improved quality of sleep many people awake energized with an enhanced mood
- Melatonin has been shown to be a potent chemotherapeutic agent in solid tumors
- It counteracts the effects of stress (as a counterbalance to cortisol)
- Melatonin acts as a potent antioxidant and free radical scavenger, immunostimulant (during its use as a chemotherapy agent patients were protected from infectious disease. T cells, T cell helper cells and antibody production were all increased; melatonin also inhibits the cytokine system during inflammation; in one particular inventive study it was noted that blind people -who should have the highest levels of melatonin – had a 30% decrease in all forms of cancer)
- Melatonin may act to reduce elevated cholesterol.
- There is good evidence in animal studies that melatonin may be therapeutic in AIDS, asthma and cataracts; perhaps even Down’s syndrome, Alzheimer’s disease and Parkinson’s disease
- Melatonin is an excellent agent for the prevention of migraines (especially ‘cluster headaches) using dosages higher than usual in the 10-15 mg range
There is some evidence that melatonin may aide in resetting the ‘age clock’:
- Studies in rats have shown that increasing melatonin by transplanting pineal glands from young rats to old rats, the rats had a 30% increase in lifespan and were more healthy showing little effect of aging
- Conversely transplanting pineal glands from older rats to younger rats accelerated the effects of aging and reduced lifespan by 20 to 30% by feeding rats a diet supplemented with melatonin the rats were healthier and more vigorous with a 25% increase in lifespan and were more resistant to disease.
There is no standard dosage for melatonin and it is generally titrated to effect. Women are more sensitive to melatonin than men and the dose is usually started at 1 to 3 mg per day. Men require higher doses of melatonin and usually are started at 3 to 9 mg per day. Dosages larger than 10 mg per day are rarely used. The maximum dosage of melatonin is considered to be 45 mg per day. Micronized melatonin has a sustained release effect with therapeutic levels sustained for six hours in comparison with the over-the-counter products which have a sustained therapeutic effect for no longer than two hours.
When discontinuing melatonin the dosage should e cut back in increments over one to two weeks to avoid rebound insomnia. Melatonin is contraindicated in pregnancy and nursing mothers. it may be contraindicated in certain instances of autoimmune disease (multiple sclerosis), immune system cancers (lymphoma or leukemia) and possibly in some forms of metastatic disease being treated with chemotherapy.
Other than the desired side effect of sleepiness, one of the side effects of high dose melatonin includes a possible reduction and suppression of estrogen and testosterone. Other side effects include prolonged grogginess (usually due to too high a dose) and change in hair color (may actually be a deeper shade and more plentiful, less gray noted). As mentioned previously, vivid dreams may occur. Usually not unpleasant, nightmares for two to three days may be one of the side effects upon initiating melatonin therapy. Adverse side effects are estimated at 1%; melatonin may have not effect in 10%.
Melatonin is extremely effective in withdrawing patients from benzodiazepines (sedatives, often used as a sleep aid) without rebound insomnia. These patients are able to use melatonin as a sleep inducing agent rather than benzodiazepines which may produce memory loss and dependence.