Insomnia and Melatonin
Melatonin is a naturally-occurring which helps in setting the body's internal clock, which regulates various mechanisms including your sleep and wake cycles. The pineal gland produces melatonin at night to help you fall asleep. Melatonin is available commercially as a health supplement. Studies confirm the benefits of melatonin supplementation for sleep/wake rhythm disturbance including insomnia and jet lag.
Effect of Melatonin on Insomnia
Melatonin supplements may help insomnia sufferers because melatonin decreases sleep-onset latency or the length of time that it takes to fall asleep.
Your melatonin level normally increases at mid- to late evening. It remains high for most of the night, and then drops in the early hours of the morning. Factors that affect melatonin levels include light exposure and age. It is believed that light interferes with melatonin production. Melatonin levels slowly drop with age. Some elderly people make very small amounts of it or none at all.
Research Evidence on Melatonin
A study published in European Neuropsychopharmacology on May 2003 suggested that melatonin may help improve sleep quality, mood and quality of life of people with weather-associated changes in mood and behavior.
Insomnia in the elderly
Reports of studies show that melatonin taken before bedtime decreases the amount of time it takes to fall asleep in elderly individuals with insomnia. Some of these studies, however, lack high quality designs and some findings show minimal or no benefits. Moreover, most of the trials have been brief in duration and long-term effects are not known.
Melatonin for jet lag
Several trials suggest that melatonin taken by mouth, started on the day of travel and continued for several days, reduces the number of days required to establish a normal sleep pattern, lowers sleep latency, improves alertness, and reduces daytime fatigue. However, more trials are needed to confirm these findings, to determine optimal dosing, and to evaluate use in combination with prescription sleep aids.
How to Use Melatonin
For symptoms of insomnia, melatonin dose range from 0.3 to 5 mg once daily, taken usually in the evening. You may to try melatonin at bedtime first, but if you find that the supplement does not work quickly enough for you, you may try taking it earlier in the evening.
Side Effects and Warnings
A safety study found that melatonin at a dose of 10 mg daily produced no toxic effects when given to 40 healthy males for a period of 28 days. ^ However, this does not prove that melatonin is safe when taken on a regular basis over the long term. Keep in mind that melatonin is not truly a food supplement but a hormone. As we know from other hormones used in medicine, such as estrogen and cortisone, harmful effects can take years to appear. Hormones are powerful substances that have many subtle effects in the body, and we're far from understanding them fully. While in one small study, use of melatonin over an 8-day period by healthy men did not affect natural release of melatonin or levels of pituitary or sex hormones, ^ another study found effects on testosterone and estrogen metabolism in men and possible impairment of sperm function. ^ Also, a small study in women found possible effects on the important female hormone called LH (luteinizing hormone). ^ Melatonin appears to cause drowsiness and decreased mental attention for about 2 to 6 hours after using it and may also impair balance. ^ For this reason, you should not drive or operate machinery for several hours after taking melatonin. In a study of healthy middle-aged and older adults, however, an extended release version of melatonin, which is said to more closely mimic natural fluctuations of the hormone in the body, did not impair mental ability or driving skills 1 to 4 hours later compared to placebo. ^ In either case, melatonin does not appear to have any "hangover" effects the following day. ^ Based on theoretical ideas of how melatonin works, some authorities specifically recommend against using it in people with depression, schizophrenia, autoimmune diseases, and other serious illnesses. One study in postmenopausal women found evidence that melatonin might impair insulin action and glucose tolerance, suggesting that people with diabetes should not use it. ^ However, another study found melatonin safe and effective for people with diabetes. ^ Because of these contradictions, we suggest that individuals with diabetes seek physician supervision before using melatonin.
Two exceedingly preliminary studies reported by one research group has led to publicized concerns that use of the supplement melatonin might increase night-time asthma. ^ However, one double-blind study of melatonin in people with asthma found evidence of improved sleep without worsening of symptoms. ^ Again, at the current state of knowledge, caution must be advised for people with night-time asthma who wish to try melatonin.
There is some evidence that melatonin may interfere with the ability of blood to clot normally, at least in healthy volunteers, ^ though the clinical significance of this finding is at yet unknown.
Maximum safe dosages for young children, pregnant or nursing women, or those with serious liver or kidney disease have not been established.
Supplements of Melatonin are also used to help cure jet-lag.
Leppämäki, S, et al., Effect of controlled-release melatonin on sleep quality, mood, and quality of life in subjects with seasonal or weather-associated changes in mood and behaviour. **Eur Neuropsychopharmacol. 2003 May;13(3):137-45.