Melatonin

Melatonin is a hormone that is produced from the pineal gland in a circadian pattern and plays a role in the initiation of sleep.

The production and release of this hormone is connected to the time of day, ideally increasing when it is dark and decreasing when it is light. Melatonin and cortisol follow opposite circadian patterns but are not cross-regulated in a negative feedback manner.

The production of melatonin decreases with age.

Early morning melatonin is somewhat representative of melatonin produced during the dark period throughout the night if saliva is collected within the first 30 minutes of awakening. Light exposure in the morning will begin to rapidly deplete melatonin levels in the bloodstream and saliva.

Melatonin is known to have many different beneficial effects in the body. It helps slow the aging process, is a potent antioxidant, inhibits formation and growth of tumors such as breast and prostate cancers, and helps regulate the synthesis of the sex-hormones estradiol and progesterone (melatonin increases progesterone and decreases estrogens).

If sleep issues are problematic melatonin supplementation may be helpful. Treatment with melatonin has been found useful in people with circadian rhythm sleep disorders or frequent travel through time zones. If melatonin is taken as a supplement (available OTC) to correct low levels or treat a condition, the timing and dosage are important to its effectiveness, especially as a sleep aid. Response to supplemental melatonin can be very individual. For optimal benefit it is best to work with a health care provider familiar with melatonin dosage and timing. Excessive dosing can result in spillover of melatonin into daylight hours, causing excessive sleepiness during the day, and disruption of the normal melatonin-cortisol circadian rhythms.