Melatonin does more than promote sleep

Melatonin is considered the “sleep hormone” as it is usually recommended for supporting a good night’s sleep, but it turns out that the benefits of melatonin don’t just stop at sleep.

Understanding how melatonin works to support your immune system, weight loss and disease prevention can pave the way to better health.

Let’s take a closer look at how melatonin works.

Natural relaxation

Melatonin is produced mainly by the pineal gland, which is a pea-sized gland located above the middle of the human brain.

It’s a misconception to think of melatonin as a natural sleeping pill.

Instead, it is a hormone that promotes a state of calm to help you feel relaxed and fall asleep faster.

Low levels of light encourages melatonin production, which regulates the body’s circadian rhythm, i.e. the sleep-wake cycle.

Melatonin production can be disrupted by any interference in natural darkness (such as prolonged exposure to light) and this can affect the body’s sleep cycle.

Poor sleep habits, shift work and too much screen time can also greatly upset melatonin production.

Your body produces melatonin during rest periods at night, so when something like jetlag or night shift work disrupts your sleep cycle, you’ll start experiencing sleep issues.

So, cultivating a strict sleep schedule – going to sleep and waking at the same time each day, including weekends – can work wonders to turn around poor sleep quality.

Too much screen time on your phone, tablet, computer and/or TV in the hours leading up to bed can also disrupt melatonin production.

That’s because you are extending your exposure to blue light into the evening hours when that should only occur during the day.

Removing all screen time and dimming the lights several hours before bed can help recalibrate your circadian rhythm.

Try a blue light screen protector that filters blue light from reaching your eyes to reduce the exposure if you must work in the evening hours.

Powering mitochondria

Melatonin is a powerful antioxidant that neutralises free radicals and protects against chronic illnesses such as cancer, heart disease and Alzheimer’s disease.

It shines by supporting mitochondrial function.  Melatonin has the rare ability to enter your mitochondria, where it helps “prevent mitochondrial impairment, energy failure and apoptosis of mitochondria damaged by oxidation.” (Antioxidants, 2020).

Mitochondria are like tiny powerhouses in our cells, which break down nutrients to produce energy for our cells.

Indeed, melatonin is found in higher concentrations in the mitochondria than other sub-cellular locations.

When the body’s tissues experience oxidative stress – i.e. when antioxidants are losing their fight against free radicals – the cells’ detoxification abilities are impaired, leaving the body vulnerable to diseases such as:

• Rheumatoid arthritis
• Chronic obstructive pulmonary disease (COPD)
• Inflammatory bowel disease
• Certain cancers (leukaemia, melanoma, breast, prostate, colorectal, gastric, lung and ovarian)
• Cardiovascular diseases
• Huntington’s disease
• Wilson’s disease
• Diabetes
• Acquired immunodeficiency syndrome (AIDS), and
• Viral illnesses such as colds, the flu and Covid-19.

The mitochondrial membranes allow for the rapid uptake of melatonin, enabling this antioxidant hormone to annihilate free radicals and help prevent disease.

Melatonin benefits for the immune system

Our immune system works hand-in-hand with melatonin to fight off diseases and infection.

White blood cells have melatonin-specific receptors and the enzymatic machinery required to synthesise melatonin.

Melatonin also triggers the production of T-cells, which combats infected host cells, activates other immune cells and helps regulate immune response.

In addition, melatonin enhances the phagocytosis process, which removes pathogens and debris from cells.

The protective effects of melatonin due to its antioxidant powers also help in regulating and preventing chronic inflammation.

It is also known to inhibit NLRP-3 inflammasomes, which lead to respiratory distress in the lungs.

NLRP-3 inflammasomes are also associated with diseases of the central nervous system, including:

• Meningitis
• Subarachnoid haemorrhage
• Parkinson’s disease
• Cerebral haemorrhage
• Glutamate-associated brain damage
• Ischaemic stroke.

Production of melatonin diminishes with age, contributing to immune dysfunction and increasing oxidative stress, inflammation, and infection susceptibility (Ref).

Melatonin benefits for heart, brain and weight

Melatonin also contributes to a healthy cardiovascular system.

It helps regulate the function of the mitochondria in the heart, brain, kidneys and the renin-angiotensin system – the hormone system responsible for regulating blood pressure, fluid and electrolyte balance, as well as blood circulation.

It also plays a protective role in the brain, where its antioxidant properties fight the free radicals that cause oxidative stress.

Melatonin might serve as potential therapy for certain neurodegenerative disorders, such as:

• Huntington’s disease
• Amyotrophic lateral sclerosis (ALS)
• Alzheimer’s disease
• Parkinson’s disease.

The protective effect of melatonin on the mitochondria has also been shown to have an impact on diabetes, insulin resistance and obesity.

Melatonin regulates insulin secretion and decreases blood glucose levels.

Research suggests that melatonin does the following:

• Tips the energy balance in the direction of reducing food intake and increasing brown adipose tissue (also known as brown fat or “good” fat) energy expenditure, thus preventing excessive body weight gain.
• Regulates energy homeostasis and influencing feeding, energy storage and expenditure.
• Regulates glucose metabolism by inducing insulin resistance at night and insulin sensitivity during the day, which is closely associated with nocturnal fasting and daytime feeding.

Supplements can help with melatonin deficiency, which occurs naturally with ageing and/or frequent night shifts.

Even at higher dosages, melatonin is generally safe, but do seek the guidance of a medical professional for dosage recommendations.

Can melatonin cause Alzheimer's?

Melatonin supplements are generally safe and are used to treat insomnia. They may modestly improve sleep, which could theoretically lead to long-term protection against Alzheimer's. A review and meta-analysis on melatonin treatment in Alzheimer's published in Neuroscience & Biobehavioral Reviews (Aug 2021) showed individuals with Alzheimer's improved with more than 12 weeks of treatment.

Melatonin benefits for COVID-19

Assisting sleep and rest is already an immune system-supporting benefit, but melatonin has more to offer. It is a powerful antioxidant that supports your immune health, brain, eyes, digestion, and more. It may even be helpful when it comes to COVID-19. 

Data from Cleveland Clinic supports the use of melatonin. Here, the researchers analyzed patient data from the Cleveland Clinic’s COVID-19 registry using an artificial intelligence platform designed to identify drugs that may be repurposed.

"Patients who used melatonin as a supplement had, on average, a 28% lower risk of testing positive for SARS-CoV-2. Blacks who used melatonin were 52% less likely to test positive for the virus."

As stated in the FLCCC (Front Line Covid-19 Critical Care) I-MASK+ prevention and treatment protocols, COVID-19 prevention and treatment are further enhanced if melatonin is combined with vitamin D, vitamin C, quercetin (a plant flavonol) and zinc supplements.

Based on melatonin’s therapeutic potential and well-established safety profile, it has been suggested those at higher risk for severe illness and complications from viral respiratory infection, including the elderly and those with chronic medical conditions, may benefit most from regular use of 3–10 mg melatonin at bedtime (Ref). 

Fluvoxamine (Selective Serotonin Reuptake Inhibitor) might also exert beneficial effects in COVID patients through its well-characterized ability to substantially increase (~ 2–3-fold) night-time plasma levels of melatonin. This increase appears to result from fluvoxamine’s inhibition of the melatonin-metabolizing liver enzymes (von Bahr et al. 2000).

Some researchers have suggested high doses of melatonin, ranging from 50 to 200 mg twice daily, might help treat patients hospitalized for severe acute respiratory illness (Ref).

In a small Philippine case series study of 10 hospitalised COVID-19 patients, high dose melatonin (hdM) was given in addition (adjuvant) to standard therapy. According to the authors:

"High dose melatonin may have a beneficial role in patients treated for COVID19 pneumonia, in terms of shorter time to clinical improvement, less need for MV, shorter hospital stay, and possibly lower mortality."

One study found that among 26,779 people tested for COVID-19, those who reported using melatonin supplements were less likely to have the disease (PLoS Biol. 2020).

In another observational study that followed 11,672 individuals, melatonin use was associated with a reduced risk of testing positive for a common, highly infectious respiratory virus (Ref).

Another study looked at data from 791 patients intubated for respiratory support during an outbreak of a severe acute viral respiratory illness and 2,981 patients needing the same level of respiratory support for other reasons. The use of melatonin, most often for sleep issues, during the intubation period was associated with significantly improved outcomes in both groups and increased the likelihood of survival in virus-infected patients who required mechanical ventilation (Ref).

Melatonin also helps recharge glutathione as glutathione deficiency has been linked to COVID-19 severity.

As of November 2021, there are 10 published clinical studies (constantly updated) of melatonin for treatment and prevention in COVID-19 and the results are promising even when it's given as a late treatment.

Clinical Trials are also currently underway to investigate the benefits of melatonin against COVID-19. Ultimately, the results of the above trials will offer more definitive evidence.

Safety: If you take a melatonin supplement, please take note: Too much can cause daytime sleepiness. There is no federal RDA nor any formal advice on supplement dose ranges. Based on an on-going Spanish study, a 2 mg daily dose protocol is being investigated for prevention of COVID-19. Do take note that the dosage for 'prevention' and 'treatment' is different, For prevention or maintenance, a lower dosage is normally recommended whereas a 'treatment' or 'therapeutic' dosage is normally higher.

Typical doses of 1–10 mg/day melatonin appear to be safe for short-term use (Source). Reported side effects, which are usually minor, include dizziness, headache, nausea, upset stomach, rash, and sleepiness. However, some reports have linked high blood levels of melatonin with delayed puberty and hypogonadism.

Studies have not evaluated melatonin supplementation during pregnancy and breastfeeding, but some research suggests that these supplements might inhibit ovarian function (Source). Therefore, some experts recommend that women who are pregnant or breastfeeding avoid taking melatonin.

Online Shopping Guide

Before adding a new supplement to your routine, discuss its use with your healthcare provider, especially if you have an underlying health condition or are taking medication.

While many of the supplements may be available in local stores, it may be more convenient or affordable to shop for them online on Amazon:

• Amazon Best Sellers in Nutritional Sleep Supplements

Disclaimer: The information provided is for educational and communication purposes only, and it should not be construed as personal medical advice. Information published in this article is not intended to replace, supplant or augment a consultation with a health professional regarding the reader’s own medical care.

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