The pineal gland in the brain secretes a hormone called melatonin, which helps maintain the body’s internal clock and regulates other hormones.
The body clock, termed the circadian rhythm, is a 24-hour cycle that plays a major role in determining when we go to bed and when we wake up. It’s an ancient trait, no doubt dating to times when it was wise to hunker down because there was no artificial light, and predators abounded.
When it gets dark, your body produces more melatonin, dropping off as the light returns at dawn. That’s why artificial electronic light from televisions and computers can interfere with sleep because the bright lights in the evening disrupt the cycle. Similarly, being deprived of daylight also can throw the body clock off, which accounts for problems like jet lag, shift work health issues and other disturbances.
Melatonin is more than a sleep inducer. It also controls female reproductive hormones, determining when a woman will menstruate, the duration and frequency of menstrual cycles, and when menopause should begin. Some studies have indicated that pre-eclampsia, a pregnancy complication, may be tied to lower levels of melatonin.
As we age, sleep patterns change, and research has shown that melatonin may play a role in that shift. Children have the highest levels of melatonin, and there is a gradual change in that as we age, getting down to the point where some elderly may experience sleep problems and wake up earlier than when younger.
Melatonin also has antioxidant properties and is believed to strengthen the immune system.
Melatonin Roles in Sleep
The available research seems to indicate that melatonin does help with sleep cycles, particularly for the jet-lagged or shift workers whose circadian rhythms are thrown off by the transition from a “normal” sleeping schedule by travel or employment.
When taken for short periods, melatonin has been found to be more effective in controlled studies using placebos in reducing time to fall asleep, increasing the number of sleeping hours and boosting daytime alertness. The changes aren’t drastic, though – research has shown that the time to fall asleep is only changed by minutes, not hours.
When studies have given healthy people melatonin in a wide range of doses, the results haven’t shown much promise in those under age 55. However, for the seniors in the group, melatonin did help that group fall asleep faster, sleep more soundly and improved daytime alertness levels. For those with insomnia, that’s a definite quality of life improvement.
Other Uses of Melatonin
Beyond sleep issues, melatonin has been found to help with other body functions. Here are some issues that have been studied.
Heart disease – Some studies have shown melatonin to have anti-inflammatory and protective effects on the heart. It may lower blood pressure and improve cholesterol levels, but the direct link between dosage and benefits has not been established.
Benzodiazepine Withdrawal – Those who are weaning themselves from Xanax, Valium or Ativan can be helped by melatonin. Insomnia is often a side effect of withdrawing from these drugs, and melatonin can help with those sleep issues. Of course, combining melatonin with those drugs is a no-no unless under a doctor's supervision.
Menopause – There are studies that suggest melatonin helps prevent bone loss in perimenopausal women and may restore quality of life. However, it can’t do anything for hot flashes or some other symptoms. The long-term effects of melatonin on menopause are not yet known.
Breast Cancer – Low melatonin levels may have a connection with a risk of developing breast cancer -- women with the disease have been found to have lower melatonin levels. Lab tests have shown that low melatonin levels seem to stimulate the growth of certain breast cancer cells, while adding melatonin slows their growth. Another added benefit of melatonin is preventing lowered blood platelets, a good thing if undergoing chemotherapy, which often leads to bleeding complications.
Prostate Cancer – Similarly, men with prostate cancer have lower melatonin levels than men who don’t have the disease. Melatonin has been shown to block the growth of prostate cancer cells in lab conditions, but some other tests shows the drug seems to improve survival rates in men with metastatic prostate cancer.
Attention Deficit Hyperactivity Disorder and Autism – Melatonin has been found to be an effective sleep aid for those afflicted with these disorders, although behavioral symptoms remain unchanged.
Fibromyalgia – A significant drop in symptoms for this disease, characterized by aches and pains, has been linked with melatonin levels.
Sunburn – Melatonin in lotions, ointments and gels has been found to block the sun’s rays and prevent burning in several studies. Some of the studies used vitamin E combined with melatonin in a topical mixture.
Irritable Bowel Syndrome (IBS) – Melatonin can help with the abdominal pain that is common in this disease. But it’s still unknown whether it can help in the regulation of bowel movements or with the bloating that accompanies the condition.
Epilepsy – The duration and frequency of epilepsy seizures decreased in some children engaged in melatonin studies, but some had the opposite reaction, increasing the number of seizures.
Sarcoidosis – Melatonin helped pulmonary sarcoidosis patients in some studies.
Assisted Reproduction – Egg maturation and pregnancy rates were improved by melatonin supplement ingestion for women with polycystic ovarian syndrome.
Pain and Digestion – Minor studies have shown melatonin may help in these areas, but the research is scant to date.
Talk to a Doctor
Melatonin is something that should be taken under a doctor’s supervision. Many herbal and natural supplements on the market do not have sufficient levels of melatonin in them because the Food and Drug Administration does not monitor their production. Thus, suggested levels of the drug may not be met if taken, and the results obviously will be ineffective or inconclusive.
For adults, it is generally recommended that melatonin dosages should be one to three milligrams taken an hour before bedtime. For combating jet lag, about 0.5 to 5 milligrams should be taken before the desired bedtime at your destination, starting two to three days before your trip and continuing for two to three days after your arrival.