Does melatonin work?

We all need a little help getting to sleep from time to time, and increasing numbers of people are turning to supplements to help them wind down in the evening. One of the most popular sleep aids is melatonin. But does melatonin work? 

We asked Michael J. Breus, clinical psychologist and fellow of the American Academy of Sleep Medicine, aka The Sleep Doctor, for the lowdown. "It all depends upon several factors," he said. "Does the patient have a melatonin deficiency? And have they been tested? If so, and you do get them the right dose, then yes, melatonin can be very effective."

"However," he added, "you should always remember that melatonin isn’t a sedative – but it is a powerful facilitator."

What is melatonin?

Melatonin is a hormone that occurs naturally in the human body in response to darkness. Produced by the pineal gland in your brain, its primary function is to help encourage and moderate sleep. Your levels of melatonin will rise in the evening before peaking in the early hours of the morning, declining once more during daylight hours. 

But that’s not all it does. A 2014 study from the Department of Cellular and Structural Biology at the University of Texas showed that melatonin is a great antioxidant, helping to protect the health of your cells and your brain. 

But as Breus explained, there are a variety of reasons why your levels of melatonin might diminish — your advancing years being a chief culprit. From the ages of 40 to 45, naturally occurring melatonin begins to decline. Research from the Insomnia Study Group of the Spanish Sleep Society found that a 70-year-old adult has just 10% of the melatonin production of prepubescent children — the period when levels are at their highest. "You never completely lose your melatonin but as we age it can lower in total production," Breus said. "The time in which it is produced can change too."

Melatonin levels can be affected by a range of factors, some of which are within your control and others that aren’t. This can include age, stress levels, medication and irregular sleeping patterns caused by shift work. Your environment is another example. All too often the light inside and outside our homes can prevent our melatonin levels from rising naturally and this can cause disrupted sleep patterns. Blue light from computers, cell phones and tablets can also disrupt melatonin production if used before bedtime.

In some cases, the only option for people to restore their melatonin levels and achieve better sleep is by taking melatonin supplements. These come in a range of forms, including liquids, pills and even chewable tablets. However, it's best to consult a doctor before taking them, and manage your own expectations about what melatonin might do for you and your sleep. 

Does melatonin really work?

Melatonin does work, but it's worth noting that these supplements are not a panacea and won’t help to ‘cure’ other sleep disorders like sleep apnea. There is also no clear evidence to suggest that taking melatonin actually improves sleep or sleep quality. "Think of them as a sleep regulator and not a sleep initiator, Breus said.

A recent survey published in the Journal of the American Medical Association examined data from the National Health and Nutrition Examination Survey that had been collated between 1999 and 2018 and found that U.S. adults were taking more than twice the amount of melatonin they were a decade earlier. 

For some people suffering with disrupted sleep, melatonin supplements can help in restoring a degree of normality to sleep patterns. Typically, there are three types of people who will benefit most from additional melatonin. If you’ve been traveling and are suffering from jetlag, then a dose of melatonin can help you back on track when it comes to sleeping. Similarly, shift work, especially overnight, can throw your circadian rhythm and melatonin production out of sync. Melatonin supplementation can help to trick your body into thinking it’s time for sleep, even if it's light outside.

Finally, if you have a melatonin deficiency then the right dose of a melatonin supplement can be extremely effective. "If you’re taking melatonin in pill form, I recommend taking 0.5 mg to 1.5 mg about 90 minutes before bed," Breus said. "If you’re taking melatonin in liquid form, take that same dosage but half an hour before bedtime."

Signs of a melatonin deficiency include daytime fatigue, trouble with concentration and focus, anxiety and depression, trouble falling asleep for a prolonged period, and feeling "groggy" in the morning. 

If you are concerned that you might be melatonin deficient, you can arrange a test with your doctor. Home tests are increasingly popular too.

What are the risks of taking melatonin?

Generally speaking, less is more when it comes to taking melatonin supplements, but there are certain considerations to discuss with a medical professional before you embark on a course.

If you're pregnant, plan on getting pregnant or are breastfeeding, you shouldn’t take melatonin. Similarly, those taking antidepressants should refrain as it can make the symptoms of depression worse. "People with bleeding disorders, people who’ve had an organ transplant and patients with diabetes should also think twice as melatonin can have negative side effects," Breus added. "And I would never recommend it for anyone under 18."

Melatonin supplements have also been known to raise blood pressure, including in those already taking medications to control it. Side effects of melatonin may also include headaches, nausea and dizziness. If you are taking melatonin supplements, you should not drive vehicles or operate machinery after taking it.

If melatonin does make a difference to your sleep and you don’t suffer any adverse reactions, it will be safe to take each night for anything up to two months. Do remember, however, to cease taking it if it isn’t working for you — you should know within two weeks if that's the case.

Originally published on Live Science.