Many people are affected by sleep disorders.

Although a common problem, poor sleep can have serious consequences.

Poor sleep can drain your energy, reduce your productivity and increase your risk of diseases like high blood pressure and diabetes ( 1 ).

Melatonin is a hormone that tells your body when it's time to go to bed.

This article explains how melatonin works and how much it needs to be consumed.

Melatonin is a hormone that is naturally produced by the body.

It is produced by the pineal gland in the brain, but also in other areas such as the eyes, bone marrow and intestines ( 2 , 3 ).

It's often referred to as the "sleep hormone" because high levels can help you fall asleep.

Melatonin itself, however, will not directly put you to sleep. It's just letting your body know it's night, allowing you to relax and fall asleep more easily ( 4 ).

Melatonin supplements are popular with people struggling with insomnia and jet lag. You can get it without a prescription in many countries.

Melatonin is also a powerful antioxidant that can provide a variety of other benefits.

It may even help support eye health, treat stomach ulcers and heartburn, relieve tinnitus symptoms and even increase growth hormone levels in men.

Melatonin works in concert with your body's circadian rhythm.

In simple terms, the circadian rhythm is your body's internal clock. They know when it's time to sleep, wake up, and eat.

Melatonin also helps regulate body temperature, blood pressure and hormone levels ( 5 , 6 ).

Melatonin levels rise in your body when it's dark outside, signaling your body that it's time to sleep ( 7 ).

It also binds to receptors in the body and can help you relax. For example, melatonin binds to receptors in the brain to reduce nerve activity. In the eyes, it can help lower levels of dopamine, a hormone that helps you stay awake ( 8 , 9 , 10 ).

Although the exact way in which melatonin helps induce sleep is unclear, there is evidence that these processes may help induce sleep.

Conversely, light suppresses melatonin production. That way your body knows it's time to wake up ( 11 ).

Because melatonin helps your body prepare for sleep, people who don't get enough of it at night can have a hard time falling asleep.

There are many factors that can cause low levels at night.Stress, smoking, too much light at night (including blue light), too little daylight during the day, shift work and aging affect melatonin production ( 12 , 13 , 14 , 15 )

Taking a melatonin supplement can help smooth out low levels and normalize the internal clock.

Taking melatonin before bed has been shown to help you fall asleep ( 16 , 17 , 18 , 19 ).

In an analysis of 19 studies of people with insomnia, scientists found that melatonin reduced the time it took to fall asleep by an average of 7 minutes.

In many of these studies, people also reported significantly better sleep quality ( 19 ).

Melatonin can also help with jet lag, a temporary sleep disorder.

Jet lag occurs when your body's internal clock is not synchronized with the new time zone. Shift workers may also experience jet lag symptoms as they work during a time normally scheduled for sleep ( 20 ).

Melatonin can help reduce jet lag by synchronizing your internal clock with the daylight saving time ( 21 ).

For example, an analysis of 10 studies examined the effects of melatonin in people who crossed five or more time zones. The scientists found that melatonin is remarkably effective in reducing the effects of jet lag

The analysis also revealed that both lower doses (0.5 mg) and higher doses (5 mg) were equally effective in reducing jet lag (22).

Taking melatonin may also provide you with other health benefits.

Current evidence suggests that melatonin supplements are safe, non-toxic and non-addictive ( 39 ).

That being said, some individuals may experience mild side effects such as drowsiness, dizziness, headaches, and nausea.

Melatonin can also interact with various medications. These include blood thinners, blood pressure medications, and antidepressants ( 40 , 41 , 42 ).

If you are taking any of the above, it is best to speak to your doctor before you start taking it.

There is also concern that taking too much melatonin will stop your body from making it naturally. However, several studies have shown that taking melatonin does not affect the body's ability to produce it on its own ( 43 , 44 , 45 ).

Melatonin is an effective supplement that can help you fall asleep, especially if you suffer from insomnia or jet lag. It may have other health benefits as well.

If you want to try melatonin, start with a lower dose of 0.5-1 mg taken 30 minutes before bedtime. If this doesn't work, you can increase your dose to 3 to 5 mg