Melatonin: Types, Symptoms, Causes, Risk, Treatments and More

What Is Melatonin?

Melatonin is a hormone naturally produced by the body. It is made by the pineal gland that is a small gland located in the brain. The hormone is for controlling the sleep and wake cycles of a person. Very small amounts of melatonin can also be found in certain foods like meats, fruits, vegetables and grains. It can also be made synthetically for medicinal use.

Melatonin: Types, Symptoms, Causes, Risk, Treatments and More

What Are The Functions of Melatonin?

It is often taken to adjust the internal clock of the body in such cases as jet lag, people who have shift changes (shift-work disorder) and for helping blind people establish a day-night cycle. There are many other uses for melatonin including treating insomnia and other sleep problems. It is also a sleep aid that can be used after discontinuation of benzodiazepine drugs. The other uses are for Alzheimer’s disease, depression, chronic fatigue syndrome, migraine, headaches and ringing in the ears.

What Are The Medical Uses of Melatonin?

Melatonin is likely effective for:

Sleep Disorders In People Who Are Blind – Taking melatonin orally helps improve sleep disorders in both children and adults who are blind.

Difficulty Falling Asleep – Also known as a delayed sleep phase syndrome, melatonin helps decrease the length of time needed by a person to fall asleep. However, after a year of stopping this treatment, the sleeping problem usually returns.

Sleeping problems in people with a disturbance in their sleep-wake cycle – melatonin helps people with disturbed sleep-wake cycles. It may also shorten the time it takes for children with developmental disabilities to fall asleep. It also helps improve sleep quality in people who have reduced rapid-eye-movement sleep. It is also effective for elderly people who have sleep-wake cycle disturbances and dementia.

Melatonin is possibly effective for:

Withdrawal from benzodiazepines – In controlled release form, melatonin taken orally seems to help people who are suffering from insomnia from withdrawal from benzodiazepines.

High Blood Pressure – In controlled release form, melatonin taken orally right before bedtime seems to lower blood pressure in people who have hypertension.

Insomnia – For those with primary insomnia (when it is not connected to any medical or environmental cause), melatonin taken orally seems to shorten the time it takes to fall asleep. According to one research, it only shortens the time by around 12 minutes and does not appear to improve sleep efficiency. Many people say melatonin makes them sleep better although there are conflicting results from studies. There is evidence that melatonin is more effective for older people which is most likely because they have less melatonin produced by the body.

Jet Lag – Most research shows that melatonin helps improve particular symptoms of jet lag. However, it may not help in shortening the time it takes for people suffering from jet lag to fall asleep.

Reducing Anxiety Prior To Surgery – Melatonin seems to help reduce anxiety before surgery. In fact, it may be as effective as midazolam, the conventional medication prescribed by doctors. It has notably lesser side effects compared to the conventional medication although it is not always effective due to unclear reasons.

Tumors – In some cases, taking high doses of melatonin in conjunction with other cancer treatments like chemotherapy might reduce the size of the tumor and improve the patient’s survival rate as well.

Sunburn – Melatonin, when applied to the skin prior to sun exposure, may be helpful in preventing sunburn.
Low blood platelets or thrombocytopenia – melatonin taken orally may help improve low blood platelet counts from cancer and other disorders.

Is Melatonin a Good Dietary Supplement?

Melatonin is one of the most popular dietary supplements for addressing sleep problems and improving sleep quality today. It is effective in most cases of sleep problems like difficulty falling asleep and it is effective in establishing a regular sleep-wake cycle. It is a good dietary supplement but due to unclear reasons, it is not always effective. Ask your health care professional whether taking melatonin as a dietary supplement can help treat your medical problems.

Video: What is Melatonin or Pineal Gland?

What Are The Possible Side Effects of Melatonin?

Melatonin is safe but may cause side effects on certain people when taken long-term. It has been used safely for up to two years by some people. However, the long-term side effects can include headache, slight depression, sleepiness during the daytime, dizziness, irritability and stomach cramps. Take note that you shouldn’t take melatonin then use machinery within five hours after.

Is Melatonin Easily Available?

Melatonin can easily be purchased in supplement stores and supermarkets since it is a very popular dietary supplement today.


Melatonin is a very important hormone that is directly connected to the sleep and wake cycle of the body. Hence, deficiency of the hormone can lead to sleep problems like insomnia. If you have difficulty sleeping or often find that you have an unstable sleep-wake cycle, you need to consult your health care provider to determine if it is because of melatonin deficiency or other health problems/conditions.

[1] Hardeland, Rüdiger; Pandi-Perumal, S.R.; Cardinali, Daniel P. (2006). "Melatonin". The International Journal of Biochemistry & Cell Biology
[2] Tan, Dun-Xian; Zheng, Xiaodong; Kong, Jin; Manchester, Lucien; Hardeland, Ruediger; Kim, Seok; Xu, Xiaoying; Reiter, Russel (9 September 2014)
[3] Boutin JA, Audinot V, Ferry G, Delagrange P (August 2005). "Molecular tools to study melatonin pathways and actions". Trends Pharmacol


Sam Kramer is a Registered Dietitian, Licensed Dietitian Nutritionist, Six Sigma Green Belt Certified, and Certified Sports Nutritionis

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