The benefits of melatonin extend beyond helping you get a good night’s rest, benefitting many areas of a person’s health.

Here, we will discuss the role of melatonin in alleviating depression, multiple sclerosis, cancer and gastroesophageal reflux disease (GERD).

Stabilising circadian rhythm

The amount of natural light exposure influences one’s mental and physical wellness. Melatonin levels rise at night due to the absence of natural light, signalling to your body that it’s time to wind down and go to bed.

But when you are exposed to bright artificial lights from your phone, TV and other devices, this tricks your system and suppresses melatonin levels. Blue light from electronic screens has been found to be quite damaging to the process of maintaining a good sleep pattern.

However, because light sources that fall in the red and orange spectrum do not affect melatonin production, light therapy has been found by many studies to be very effective in alleviating depressive symptoms.

It is thought that the effectiveness of light therapy is due to how it restores proper melatonin levels and synthesis, thus repairing the circadian rhythm.

Melatonin and multiple sclerosis

Multiple sclerosis (MS) is linked with vitamin D deficiency due to lack of sun exposure, but new research indicates that proper melatonin levels may influence whether a person develops autoimmune diseases like MS and seasonal affective disorder (a condition that occurs in countries with colder seasons).

Neuroscientist Mauricio Farez at the Dr Raúl Carrea Institute in Argentina led one such study for Neurological Research, which looked at 139 MS patients living in Buenos Aires.

Approximately 32% of the patients experienced fewer relapses during the autumn and winter months, compared to spring and summer seasons.

In commenting on the study, the Scientific American Journal noted: “MS flare-ups should decrease during warmer, brighter months when people receive more exposure to sunlight and thus produce more vitamin D, which also has anti-inflammatory properties.

“But some studies, including this one, show that relapses increase in the spring and summer, pointing to the possibility that other environmental factors, such as melatonin levels, are involved.

“Melatonin regulates pathways central to the immune response, so these results may pertain to other autoimmune diseases, particularly where seasonal flare-ups occur, such as lupus and rheumatoid arthritis…”

Although we do not have cold seasons here in Malaysia, individuals who work night shifts might experience the same effects of overexposure to bright lights.

Light at night causes disruption of the master circadian clock, disruption of endocrine function and suppression of melatonin secretion that alters the immune function.

Melatonin and cancer

Melatonin may be important in cancer treatment as it protects against the toxic effects of radiation therapy.

Melatonin receptors are present throughout the cells in your body, including cancer cells. Melatonin is cytotoxic, which means that it can induce tumour cell death.

It has a placating effect on other reproductive hormones apart from oestrogen, which may be why melatonin appears most effective in fighting against sex hormone-driven cancers, including ovarian, endometrial, prostate, testicular and breast cancers.

In 2004, the first clinical trial evaluating melatonin’s effects in patients with lung cancer was conducted by the Life Extension Foundation, in collaboration with Cancer Treatment Centers of America.

Researchers found a tumour response in just over 29% of those receiving melatonin at night; 8% of those receiving it in the morning; and 10.5% of placebo recipients.

Melatonin also helps fight cancer in the following ways:

• Acts as an antioxidant agent by limiting oxidative damage to DNA.

• Increases the production of immune-optimising substances, which attack mutated cells that lead to malignant cancer.

• Prevents the development of new tumour blood vessels, slowing down cancerous cells from spreading.

Melatonin and GERD

Heartburn and stomach pains after meals and at night are tell tale symptoms of GERD.

GERD might be avoidable if a person makes several lifestyle changes, such as avoiding trigger foods like spicy and greasy foods; consuming properly portioned meals in a slow and relaxed setting; eating dinner not less than three hours before bed; and maintaining a healthy weight, which reduces pressure on the stomach that causes reflux.

Medication is necessary if lifestyle and dietary changes are not enough to prevent long term damage to the oesophagus. Try a modest dose of melatonin, about 3mg nightly, in combination with omeprazole to improve any reflux symptoms.

The antioxidant effects of melatonin can protect the oesophagus from damage. It’s worth a try, as melatonin supplements in the right doses are safe, affordable and accessible.

Melatonin and tinnitus

Tinnitus is a condition of chronic ringing in the ears that can interrupt your hearing and sleep.

In a randomised, double-blind, placebo-controlled crossover study, researchers gave patients 3mg melatonin nightly (or placebo) for a month and measured the severity of tinnitus.

It was found that melatonin may have reduced the severity of tinnitus. It is a multifactorial condition that may be influenced by damage to the inner ear, medication side effects and female hormones. As a natural supplement, it does not hurt to try melatonin to see if it helps this condition.

Melatonin and pelvic pain

Pelvic pain that comes with endometriosis can be excruciating. Often, surgery is needed to remove abnormalities and mitigate some of the pain, but that may lead to problems of its own, such as digestive and fertility issues.

A double-blind, placebo-controlled trial found that a dose of 10mg of melatonin daily reduced endometriosis pain over two months. Although melatonin alone will not be able to manage endometriosis, it is a helpful pain reliever that may be safer than some pharmaceutical analgesics.

Sleep well for your health

Sometimes, oxidative damage can break down the body’s natural defences, and a possible solution could be targeted antioxidant therapies like melatonin supplements.

It adds to what’s already made by our system, making it a safe option for conditions related to oxidative stress. Since oxidative damage can occur in all our cells and tissues, and melatonin is a safe supplement that can help reduce problems, it’s very likely that melatonin will be recommended as a treatment for many more conditions in the future.

Remember, when your circadian rhythms are out of sync, less melatonin is produced by your body, which means there is less protection against free radicals that may speed up the process of ageing, cancer and other diseases.

Even if you’re having just mild trouble sleeping, there’s no harm in seeking advice on how to improve your sleep quality naturally.


Datuk Dr Nor Ashikin Mokhtar is a consultant obstetrician and gynaecologist. For further information, visit www.primanora.com. 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.