There is strong evidence that melatonin has benefits for sleep. It may increase the duration and quality of your sleep and help with insomnia. Dosage determines how it will affect your sleep.

Melatonin is a hormone that your body makes naturally. It’s produced by the pineal gland in the brain, but it’s also found in other areas, such as the eyes, bone marrow, and gut.

It’s often called the sleep hormone, as high levels can help you fall asleep.

However, melatonin itself won’t put you to sleep. It simply lets your body know that it’s time for bed so that you can relax and fall asleep more easily.

Here’s what the research says about its benefits, as well as potential side effects and risks for certain populations.

Melatonin works in tandem with your body’s circadian rhythm.

In simple terms, the circadian rhythm is your body’s internal clock. It lets you know when it’s time to:

  • sleep
  • wake
  • eat

Melatonin also helps regulate blood pressure, blood glucose, body weight, hormone levels, and body temperature.

Your melatonin levels start to rise when it’s dark outside, signaling to your body that it’s time to sleep. They then decrease in the morning, when it’s light outside, to promote wakefulness.

Because melatonin helps your body prepare for sleep, people who don’t make enough of it at night can have trouble falling asleep.

Many factors may cause low melatonin levels at night, such as alcohol consumption, smoking, caffeine consumption, shift work, aging, certain medications, and exposure to too much light at night — including blue light.

Taking a melatonin supplement may help counter low levels and normalize your internal clock, but it’s important to speak with a doctor first to determine if it’s the best option for you.

Strong evidence suggests that taking melatonin before bed decreases sleep latency — the time it takes to fall asleep — while increasing total sleep time.

A 2019 review of 11 studies demonstrated that taking melatonin before bed decreased sleep latency by almost 3 minutes and increased total sleep time by about 30 minutes, compared with a placebo.

A 2021 review of 23 studies involving people with disease-related sleep disorders found that melatonin significantly reduced sleep disturbances and sleep latency while increasing sleep duration and quality.

Additionally, melatonin may counteract jet lag, a temporary sleep disorder.

Jet lag occurs when your body’s internal clock is out of sync with a new time zone. Shift workers may also experience jet lag symptoms because they work during hours that are normally used for sleep.

Melatonin may help reduce jet lag by syncing your internal clock with the time change.

Before using melatonin, though, try implementing healthy sleep habits, such as establishing a consistent sleep schedule, limiting alcohol and caffeine consumption, and reducing your exposure to light and electronic devices before bed.

In addition to improving sleep, melatonin may help manage other health conditions.

  • Eye health: Research from 2019 found that melatonin supplements may reduce age-related macular degeneration by neutralizing free radicals and decreasing inflammation due to its antioxidant effects in the body.
  • Acid reflux and GERD: Melatonin may help alleviate acid reflux and gastroesophageal reflux (GERD) by protecting the lining of your esophagus — the tube that connects your throat and stomach — against irritants such as acid, alcohol, and nonsteroidal anti-inflammatory drugs.
  • Tinnitus: Researchers suggest that taking melatonin may help reduce symptoms of significant tinnitus, a condition characterized by ringing in the ears.
  • Migraine attacks: Several prescription drugs help treat migraine, but melatonin may also offer relief due to its ability to inhibit pain sensations.
  • Brain health: Some studies suggest that melatonin improves sleep quality and morning alertness in individuals diagnosed with Alzheimer’s disease. Still, more research is needed to understand melatonin’s effect on the brain.

If you’re considering trying melatonin for insomnia, start with a low dose supplement.

For instance, start with 0.5 to 1 milligrams (mg) 30 minutes before going to bed. If that doesn’t seem to help you fall asleep, try increasing your dose to 3 to 5 mg.

Taking melatonin in excess of 5 mg is unlikely to help you fall asleep faster. The goal is to find the lowest dose that helps you sleep.

However, it’s best to follow the instructions that come with your supplement and to talk with a healthcare professional before adding over-the-counter melatonin to your routine.

Because melatonin comes in different forms, you may also want to consult a doctor or pharmacist about the best form for you.

Current evidence suggests that melatonin supplements are safe, nontoxic, and not addictive for either children or adults.

Supplementing with melatonin long term is also likely safe. Studies have found no significant adverse events associated with daily melatonin intake in dosages of 2 to 10 mg for up to 3.5 years.

Unlike other hormones, no evidence suggests that taking melatonin affects your body’s natural ability to make its own.

However, several minor, short-lived side effects of melatonin supplements have been reported, including:

  • daytime sleepiness
  • fatigue
  • dizziness
  • headaches
  • nausea
  • a cold feeling

Despite its relatively strong safety profile, melatonin may interact with a variety of medications by either altering their effectiveness or increasing the risk of side effects.

Medications that melatonin may interact with include:

  • sleep aids or sedatives
  • blood thinners
  • anticonvulsants
  • blood pressure medications
  • antidepressants
  • oral contraceptives
  • diabetes medications
  • immunosuppressants

If you have a health condition or take any of the above medications, talk with your doctor before starting to use melatonin.

Melatonin may also interact with alcohol. Some research from 2024 suggests that moderate to heavy alcohol use reduces melatonin levels and thus disrupts sleep quality, though results are mixed.

Your natural melatonin levels are important during pregnancy.

During pregnancy, melatonin transfers to your developing baby. Melatonin contributes to the development of circadian rhythms and both the nervous and endocrine systems.

Melatonin also appears to protect the fetal nervous system. It’s believed that this hormone’s antioxidant effects safeguard the baby’s developing nervous system from damage due to oxidative stress.

While it’s clear that melatonin is important over the course of a pregnancy, few studies have examined melatonin supplementation during pregnancy.

As such, taking melatonin supplements during pregnancy is not recommended.

Additionally, although melatonin is a natural component of breast milk, no data exists on the safety of melatonin supplementation during breastfeeding. For this reason, using melatonin supplements while nursing is also not recommended.

The effectiveness of melatonin in children and adolescents is still being investigated.

A 2019 review on melatonin use in children and adolescents found that children receiving melatonin as a short-term treatment fell asleep faster and slept longer than children receiving a placebo.

A 2018 study followed up with 69 people who had been using melatonin since childhood, for about 11 years. It found that their sleep quality wasn’t notably different from that of a control group who hadn’t used melatonin. This suggests their sleep issues normalized over time.

Tolerance, dosage, and precautions

Melatonin is well tolerated in children. While some research suggests that long-term melatonin use may delay puberty — because a natural decline in evening melatonin levels is associated with the onset of puberty — more studies are needed.

Melatonin supplements for children are often sold in the form of gummies.

Some health experts recommend 1 mg for infants, 2.5 to 3 mg for older children, and 5 mg for young adults.

Additionally, because researchers don’t yet understand the long-term effects of melatonin use in children, it may be best to help your kids implement good sleep practices first before trying melatonin.

Melatonin is an effective supplement that may help you fall asleep, especially if you have insomnia or jet lag. It may also offer other health benefits.

If you’re considering melatonin, talk with a doctor or pharmacist first to find out whether it’s right for you and whether it might interact with any medications you’re taking.

Then, you can start with a low dose of 0.5 to 1 mg 30 minutes before bed. If that doesn’t help, try increasing your dose to 3 to 5 mg.

Melatonin is generally well tolerated, although mild side effects are possible.