Melatonin and Sleep: How It Works and How to Use It

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Melatonin usage in the United States has more than doubled in the past decade, according to a recent report. In a study published in JAMA, researchers found that just 0.4% of people reported taking melatonin in 1999, while that figure was up to 2.1% in 2018.

It’s worth noting that the study does not include the coronavirus pandemic years. It’s been widely reported that COVID-19 has had a negative impact on sleep patterns, so it’s no surprise that other studies have found an increase in melatonin usage over the past few years.

What is Melatonin?

Melatonin is a hormone that is naturally produced by the brain. It helps regulate our circadian rhythm, also known as the sleep-wake cycle. Melatonin supplements can also be bought over the counter as sleep aids.

How Does Melatonin Work?

Melatonin hormones are naturally released toward the end of the day. Melatonin production is related to sunlight levels; once it’s dark outside, melatonin starts to be produced. The hormone helps put the body in a state of relaxation that promotes sleep.

How Long Does Melatonin Last?

Depending on factors like your body size, dosage, and the type of melatonin, it can remain in your system for anywhere between four to eight hours. It’s important to consult your doctor to determine how much melatonin you should be taking for your body type.

Melatonin Side Effects

According to Mayo Clinic, the most common side effects of melatonin usage are:

  • Drowsiness
  • Dizziness
  • Headache
  • Nausea

Melatonin Safety

Though melatonin is generally considered safe, it’s important to take the right dose and be aware of possible drug interactions. According to Dr. Carleara Weiss, Ph.D., MS, RN and Aeroflow Sleep’s Sleep Science Advisor, “The lack of FDA regulation has created a market where high doses of melatonin and a mixture of melatonin with different compounds is available in grocery stores and pharmacies.”

This lack of FDA regulation can be dangerous: studies have found that up to 70% of labels on melatonin products do not properly reflect the supplement ingredients. “There is a very concerning risk for side effects and interactions with other drugs or supplements that one may be taking,” says Dr. Weiss.

How to Use Melatonin Properly

Given the potential risks associated with melatonin supplements, it’s important to know where to find reliable melatonin supplements and how to best take them. Take a look at some of the tips Dr. Weiss shares:

  • Only take melatonin supplements that are verified by the United States Pharmacopeial convention (USP verified).
  • Consult your doctor to ensure that melatonin is right for you.
  • Avoid taking high doses of melatonin. Consumption should be limited to 0.5mg-5mg, and it should be taken at least 30 minutes before bedtime.
  • Avoid melatonin if you are pregnant or on any medications for anticoagulants, high blood pressure, diabetes, or anticonvulsants.
  • Stop taking melatonin if you experience nausea, dizziness, excessive daytime sleepiness, or headaches.


How much melatonin should I take?

Adults should take between 0.5mg-5mg of melatonin.

How much melatonin is too much?

Though adults should not take more than 5mg of melatonin at a time, it is believed that taking more than 30mg of melatonin can be dangerous. There is more research needed to determine the dangers of taking too much melatonin.

Is melatonin safe for kids?

Short-term use of melatonin is generally considered safe for children. Studies show that children taking low doses of melatonin for short periods of time are unlikely to experience side effects. However, it's important to note that the US Food and Drug Administration (FDA) has not approved the usage of melatonin for children. Consult your doctor before treating your child with melatonin.

Can melatonin cause headaches?

Yes. Melatonin can cause headaches and it is one of the most common side effects of usage. If you are experiencing headaches while taking melatonin discontinue use.

Can melatonin cause nightmares?

Yes and no. Melatonin itself doesn't cause nightmares, but it does increase the amount of time you spend in REM sleep, which is the dreaming stage of sleep. By virtue of the fact that you'll spend more time in this stage, you are more likely to have nightmares.

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Mattress Clarity Team

The Mattress Clarity Team is here to tell you everything you need to know about sleep. Our advice on mattresses and bedding comes from hands-on testing and our teams’ combined years of expertise.


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