“7” Facts about the “Hormone of Darkness” — Melatonin

Joseph R. Anticaglia MD
Medical Advisory Board

In 1958, with the help of a team of researchers, a Yale dermatologist, Dr. Aaron Lerner discovered the hormone Melatonin, which regulates the sleep-awake cycle (circadian rhythms). The hormone promotes sleep and is produced by the pea-sized pineal gland which is located in the middle of the brain. What follows are 7 selected facts, among many, concerning the “Hormone of Darkness.”

Delayed sleep phase disorder

Children and adults with this problem are tired, go to bed but can’t fall asleep. It may take 2 or more hours beyond the customary bedtime to fall asleep. They go to sleep late and get up later than usual. Melatonin makes you go to sleep faster and get up earlier.

Melatonin in Children

Melatonin has benefited children in a number of situations with sleep-wake cycle difficulties. Delayed sleep phase syndrome, attention-deficit hyperactivity, autism spectrum are examples in which Melatonin has proven to be useful.

People Who are Blind

Children and adults, besides coping with partial or total loss of sight, have many additional challenges. One concern is that the circadian rhythm is discombobulated. Ordinarily, light enters the back of the eye and is transmitted to a special region in the brain called the SCN (suprachiasmatic nucleus).

There are neurologic connections and feedback mechanisms among the eye, SCN and the pineal gland. This feedback loop is not functioning properly in people who are partially or totally blind. This results in a de-synchronization of the biological clock causing people to experience symptoms similar to jet-lag. Melatonin has been helpful in persons with this condition.

Shift Work Disorder

Refers to men and women who work outside the conventional morning to evening working hours (6 a.m. to 6 p.m.). If an employee is working 11 p.m. to 7 a.m., the American Academy of Sleep Medicine recommends, taking Melatonin, if necessary, before going to sleep.


Melatonin production decreases with age

“Hormone of Darkness”

The production of Melatonin decreases when there’s light (daytime) and increases at night or when it’s dark — hence the name. Also, blue light decreases Melatonin and red light increases the output of the hormone.

Unfavorable Interactions

Melatonin is generally considered a safe medication especially when used on a short term basis. However, drug interactions can occur. As noted in a previous post, one is the concern about the use of Melatonin with blood thinning, diabetic, blood pressure and seizure medications.

There are other unwanted interactions of melatonin with drugs, herbs or supplements. Check with your physician or pharmacist before using melatonin with them.

Research is ongoing about the efficacy and long term safety of Melatonin. Not everyone is in agreement about the varied uses of Melatonin.


Anticaglia, Joseph R; Melatonin: What You Need to Know — Blue Light, Electrosmog, and the Third Eye; HC Smart, 2018

James JE Jan et al; Melatonin treatment of sleep-wake cycle disorders in children and adolescents; Developmental Medicine and Child Neurology; July I, 1999 Jan JE et al Clinical trials of controlled-release melatonin in children with sleep-wake cycle disorders; J Pineal Res. Aug; 29, 2000

Sanchez-Barcelo EJ; Clinical uses of melatonin in pediatrics; Int J Pediatr; June 16, 2011 Skene DJ, Arendt J; Circadian rhythm sleep disorders in the blind and their treatment with melatonin; Sleep Med; Sept 8, 2007

NIH National Center for Complementary and Integrative Health; Melatonin: In Depth; Sept 24,2017

This article is intended solely as a learning experience. Please consult your physician for diagnostic and treatment options.