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The Truth About Melatonin

Tuesday, February 25, 2020 - SleepTalk this month

What is Melatonin?

Melatonin is a hormone that is produced naturally by your body within pineal gland inside of the brain.1 Directly correlated with your sleep, it helps to regulate your body’s internal clock, also known as circadian rhythm.1

Circadian rhythms are the signals your body gives you at the same time each day which instruct your body to wake up in the morning, stay alert during the day and feel drowsy in the evening.5

Your own body's internal clock as well as the amount of light you are exposed to during the day actually influence the level of melatonin that your body produces at different intervals throughout the day.1 As the night sets in and the level of light decreases around you, your body produces a surge of melatonin.7  This process is called dim light melatonin onset or DLMO. Fatigue and sleepiness typically kick in about two hours after the surge, helping you fall asleep.7 While you are sleeping, melatonin levels remain heightened then start to drop before the sun comes up, causing you to wake up.1

To get the most benefit from your melatonin production, stay away from caffeine in the evenings, keep the lights low and avoid blue-light emitting screens before bed.4 You can also help your body produce melatonin for sleep at the right time of night by exposing yourself to as much sunlight as possible during the day.2

The Truth About Melatonin Supplements

For people whose sleep schedules have been thrown off by jet lag, shift work or late nights, taking a melatonin supplement at the right time and dose, may help get their sleep back on track.6

However, taking melatonin can be complicated. If taken at the wrong time, the additional melatonin can actually work against you.

Melatonin has been shown to have inconsistent effects on blood sugar and blood pressure that may provoke changes in either improving or worsening control. As the science is not clear at this time, melatonin should be taken with caution in these people with monitoring of the effects on blood pressure and blood glucose.7 Taken in larger quantities, melatonin can also cause prescription drugs to be less effective and has also shown to cause bad dreams and next-day foginess.6

As melatonin falls under the dietary supplements category, it is not as widely regulated as other drugs which means the quality may vary greatly by bottle.6 One study found that of the melatonin tested, 71% of the contents did not contain the ingredients listed on the label. That same study found that some of those capsules contained as much as four times the amount of melatonin as was indicated.6

Although much is known about our own melatonin production, more in-depth studies are needed to truly understand the effectiveness and safety of melatonin supplements in short and long-term use cases.3

As always, before you take any new medication or supplements, consult your health care practitioner.

1. Links, Rachael. “What Is Melatonin?”, 2018,

2. “Melatonin for Sleep: Does It Work?” Johns Hopkins Medicine, 2020,

3. “Melatonin for Sleep: Does It Work?” Johns Hopkins Medicine, 2020,

4. “Melatonin: What You Need To Know.” National Center for Complementary and Integrative Health, U.S. Department of Health and Human Services, 15 Oct. 2019,

5. Villines, Zawn. “What Is the Pineal Gland?” What Is the Pineal Gland?, Medical News Today, 1 Nov. 2017,

6. “Melatonin: What You Need To Know.” National Center for Complementary and Integrative Health, U.S. Department of Health and Human Services, 15 Oct. 2019,

7. Zisapel, Nava. “New Perspectives on the Role of Melatonin in Human Sleep, Circadian Rhythms and Their Regulation.” British Journal of Pharmacology, vol. 175, no. 16, 2018, pp. 3190–3199., doi:10.1111/bph.14116.

Tags: Sleep apnea Sleep hygiene