Melatonin - The Magical Sleep Hormone

Melatonin - The Magical Sleep Hormone

Tina Ureten

Melatonin is known as a sleep hormone and it controls our circadian rhythms. The main production site of melatonin is the pineal gland in the brain however other organs such as bowels, lungs, kidneys, bone marrow and the retina of eye also contribute to melatonin production. Its production is increased by darkness and suppressed by light, by reaching the highest level in the night and dropping down to almost zero during the day. It regulates our biological clock and plays critical role for our health. Various factors play role in the production of the melatonin, the most important factor is body’s exposure to the light.

Recent studies show melatonin is not only a regulator of the biological clock. It has many other important functions for maintaining mental and physical balance.

It has protective and therapeutic benefits in the fight against the chronic diseases such as diabetes, heart disease, cancer, dementia and Alzheimer.  It plays roles as an antioxidant and anti-inflammatory, an anti-tumor agent and boosts immune system. It shows its functions on many systems which are very important for maintaining our health.

Health Benefits of Melatonin

Melatonin is a powerful antioxidant agent.

Antioxidants can neutralize the damaging effects of free radicals and protect cells and genes. Acting as a powerful antioxidant melatonin protects the cells from external damage, reduces harmful inflammation and limits DNA damage from free radicals.

Melatonin decreases risk for diabetes.

Melatonin has been shown to effect in regulating insulin metabolism and lower the risk of developing type 2 diabetes. Lower melatonin production is linked to higher rate of having diabetes. Maintaining good melatonin levels in the night time may cut the risk for diabetes in half.

Melatonin protects against age-related brain disease, including Alzheimer’s.

Melatonin play protective role for brain cells and decreased melatonin production is associated with Alzheimer’s disease and other neurodegenerative diseases. People with Alzheimer’s tend to show lower levels of melatonin compared to age peers without the disease. Studies show melatonin slows down the accumulation of harmful proteins and amyloid plaques in the brain, which many scientists think are behind the onset of the disease.

Melatonin acts like an anti-cancer agent.

Exciting research over the past several years has demonstrated that melatonin inhibits cancer cells and tumor growth. It boosts the effect of anti-cancer treatments. It can reduce the side effects from radiation therapy and chemotherapy. It has also preventive role for some type of cancers.

Melatonin boosts immune system.

Melatonin has significant roles for healthy immune system. Animals kept under constant light, to inhibit melatonin synthesis, showed impaired immune functions. Their symptoms can be reversed by melatonin injection. Melatonin regulates human the immune system and synthesized by fighter cells, lymphocytes.


Melatonin protects cardiovascular health.

Melatonin prevents cell death under ischemic conditions. It can also prevent and even treat the damage of chronic and age-related diseases, from cardiovascular disease to cancer and neurodegenerative diseases like Alzheimer’s. 

Melatonin’s analgesic properties.

Many recent studies have demonstrated melatonin efficacy in relation to pain syndromes. Melatonin relieves the symptoms in chronic painful conditions such as fibromyalgia, migraine, chronic back pain, and rheumatoid arthritis.

Melatonin and autism spectrum disorder (ASD).

ASD children shown lower levels of melatonin comparing to kids without ASD.  It is believed that melatonin production is impaired during intra uterine development of these children. External melatonin has a positive effect on problems associated with ASD, such as sleep disturbance, anxiety, pain/sensory processing, and gastrointestinal dysfunction. Melatonin can help children and adults with ASD sleep longer, get higher quality sleep, and fall asleep more easily, with additional benefits of improved wellbeing.

Melatonin as an anti-aging agent.

There is considerable evidence for melatonin to be an effective anti- aging compound. Because of its broad antioxidant and radical scavenger properties, melatonin may act as a protective agent against UV-mediated damage in the skin

Melatonin as a supplement.

Melatonin intake has grown in the recent years, often used for the short-term treatment of sleep problems, from jet lag or shift work. It was approved for medical use in the European Union in 2007 but not approved for medical use by FDA. Many side effects are reported when melatonin is used for long term and it is not recommended.

Without following body’s natural circadian rhythm, melatonin intake actually disturbs its natural production due to following reasons:

  • To adjust correct dosage for body’s need for melatonin is very hard as it fluctuates from zero to maximum level every day. The timing of taking melatonin also have a big impact on its effect on the body.

  • Too much melatonin can throw bio rhythms out of sync and may disrupt the body’s own melatonin production and actually brings more sleep problems.

  • Body’s own melatonin makes its peak during the late stage of sleep in the night, which is very hard to adjust with different absorption and release levels of different melatonin supplements.

  • Also some studies showed actual melatonin content in many supplements on the market may vary significantly from what product labels claim.

  • A recently introduced melatonin analog, agomelatine, is also offered as alternative to melatonin but it can cause many side effects especially when it is used as anti-depressive agent.

There would be more information about how melatonin affects the overall health with more researches. Its usage to treat and prevent illnesses, including the many that become more common with aging needs more investigation.



Melatonin secretion and the incidence of type 2 diabetes

Protective Roles of Melatonin Against the Amyloid-Dependent Development of Alzheimer's Disease: A Critical Review  

Melatonin in Alzheimer's Disease: A Latent Endogenous Regulator of Neurogenesis to Mitigate Alzheimer's Neuropathology 

Melatonin, immune function and aging

The Relationship between Autism Spectrum Disorder and Melatonin during Fetal Development

Melatonin and Comorbidities in Children with Autism Spectrum Disorder

Melatonin in Antinociception: Its Therapeutic Applications

Melatonin in Chronic Pain Syndromes

Melatonin: Nature's Most Versatile Biological Signal?

 Melatonin and human skin aging