melatonin safe

Is It Bad To Take Melatonin Every Night?

Dr. Jolene BrightenPublished: Last Reviewed: Sleep Leave a Comment

Most people know melatonin as a supplement to help you sleep with bonus antioxidant benefits. It has a reputation for being safe and effective. But is it bad to take melatonin  every night? 

In this article, we’ll look at naturally occurring melatonin, the safety of melatonin supplements, and alternative non-drug sleep enhancing options. 

What Is Melatonin?

Melatonin is a naturally occurring hormone produced by the pineal gland in the brain. It plays various roles in the human body but is primarily known for regulating the circadian rhythm or the sleep-wake cycle in humans.

But, it’s not only the sleep wake cycle that it controls. Melatonin is also useful in regulating hormonal cycles linked to menstruation and fertility.

On top of that, melatonin has been shown to be a powerful antioxidant. It may help reduce inflammation and help fight free radicals, which can cause damage to cells. This antioxidant potential is also why melatonin is often used in supporting fertility.

How Does Melatonin Work In The Body?

Your body releases melatonin as darkness sets in. It peaks overnight, and slows its production as the body senses light. As you can imagine, late-night screen use and bright electric lights can mess with melatonin release and in turn, our sleep-wake cycles. If our melatonin release is interrupted, it’s not just our sleep that can suffer, but our reproductive hormones and inflammation levels can go off-kilter, too.

If Melatonin Occurs Naturally, Why Do I Need A Supplement? 

Melatonin levels can get out of sync because of things like working the night shift, using light-emitting electronic devices close to bed time (ahem…scrolling before bed), and jet lag

We also understand that natural melatonin production decreases with age. So, older adults who have difficulty sleeping may find melatonin supplementation useful.

Furthermore, melatonin has been shown to settle pre-surgery anxiety without the side effects of other pre-surgical calming medications. 

As mentioned previously, melatonin is often used to support fertility. It is often used in IVF, cases of infertility, and when women are aiming to improve egg quality. Both in the literature and clinically we see that shift workers can have a disruption in their menstrual cycle.

Melatonin supplementation has also been shown to be beneficial in cases of endometriosis. In one randomized, double-blind, placebo-controlled trial it was found that melatonin can help reduce pelvic pain in women with endometriosis.

It has also been trialled in kids with autism and attention deficit hyperactivity disorder (ADHD) because these conditions can cause issues with sleep. In a 2019 review of 18 studies it was found that melatonin worked better than placebo in both time to fall asleep and amount of sleep. At this time there is not sufficient evidence on the long term use of melatonin in children to understand if the benefits outweigh any potential risks. It’s best to work with a healthcare provider before supplementing melatonin in children.

How Does A Melatonin Supplement Work? 

Melatonin promotes sleepiness by inhibiting the signals in the brain that promote wakefulness. 

As with most supplements, when the body doesn’t have enough of something, taking a supplement is one way to increase that substance in the body.

So, for sleep difficulties, taking a melatonin supplement one to two hours before bedtime may boost your melatonin levels and help you to fall asleep.

What to Look For in a Melatonin Supplement

A higher dose isn't necessarily more effective. It may take some trial and error for you to find the right dosage for you so it is best to start low.

Melatonin Dose

Typical dosage is usually between 1 to 5 mg taken 1-2 hours before bed.

You’ll want a melatonin supplement that contains enough to be effective, but not so much that you experience “melatonin hangover” the next day. Ask your doctor for a recommendation. I usually suggest that my patients take 3 mg, and I keep close tabs on how that’s working for each individual. 

For some people, taking a formula with melatonin, which can help you fall asleep, along with ingredients like GABA that help you stay asleep can promote the best sleep.

Ingredient Quality

Not all melatonin supplements are the same. Currently in the U.S., melatonin is regulated by the Food and Drug Administration (FDA) as a dietary supplement. But what you buy over the counter is not regulated as tightly as prescription medications because they are not intended to treat or prevent disease like a pharmaceutical.

A study published in the Journal of Clinical Sleep Medicine found that the majority of over-the-counter supplements did not contain the amount of melatonin that the label indicated. It also found that over a quarter of all supplements contained serotonin. 

Serotonin is known as the happy hormone. Although it sounds like a nice idea to get a bonus hit of happy, when serotonin is taken unknowingly it can be harmful — especially for people already taking medications that alter serotonin levels such as certain antidepressants.

Besides, you want the products you buy to be what they say they are, period

Which Melatonin Supplements Are The Safest?

The safest way to supplement with melatonin is to do so under the guidance of a health professional with specialized knowledge in supplements and their safety. 

Be sure to use only professional grade supplements with a Good Manufacturing Practices (GMP) stamp so that you know you’re taking what the label says you’re taking.

Is Melatonin Safe If I Take A High-Quality Supplement? 

It depends. In the short term, a melatonin supplement is relatively safe for most people but may cause some mild side effects. Long-term use is lacking in research, so it’s best to avoid taking melatonin long term unless directed by your healthcare professional.

If you need help with sleep and are looking for alternatives to melatonin, I've got a full article on it!

Short Term 

If you’ve found a high-quality supplement through a reputable health professional, short term use is typically considered safe

However, some people experience side effects when they take melatonin. If you start with a low dose you are less likely to experience these possible side effects

Side effects 

The most common melatonin side effects include:

  • Daytime sleepiness
  • Dizziness
  • Headaches
  • Nausea 

Some less common side effects can include:  

  • Agitation
  • Mood swings
  • Fatigue or drowsiness
  • Skin irritation
  • Nightmares
  • Palpitations 

The side effects typically settle on their own within a few days, or go away once you stop the supplement. It is important that you check in with your health professional about your side effects. 

Long Term

Melatonin influences our circadian rhythm. But it can also influence other rhythms and cycles of the body, including the female menstrual and reproductive hormone cycles. Currently melatonin’s impact on female reproductive cycles is under investigation

Melatonin supplementation hasn’t been studied for long enough to know what the long-term impacts are on the body and the hormonal system. So it’s best to avoid long-term use in children, and adolescence.  

For Some People, Melatonin Is Not A Safe Supplement

While it is always best to check with your doctor before beginning a supplement, especially if you're on a medication, there are two instances where it is definitely best to hold off until you get your doctor's approval.

Pregnancy or Breastfeeding 

If you are pregnant, breastfeeding, or pumping milk for your baby, avoid taking melatonin until you’ve spoken with a health care provider. Melatonin, both what your body naturally makes and supplements, can pass through the breastmilk. Supplementing during pregnancy and breastfeeding hasn’t been proven to be unsafe, but it hasn’t been proven to be safe either. So, it’s best to avoid it until further research is available.

Liver or Kidney Conditions

If you have any concerns with your liver or kidneys, don’t take melatonin unless you’ve consulted with your doctor and received the OK. Melatonin is metabolized (broken down) by the liver and excreted from the body via the kidneys. So, if you have pre-existing conditions that affect either of these organs, your body may struggle to break down and remove melatonin from your body. 

Will A Melatonin Supplement Interact With Other Drugs Or Supplements? 

If you are taking any other medications or dietary supplements, it is best to check with your treating health professional or pharmacist about possible interactions. In particular, if you are taking other sedatives or anti-anxiety medications, you should take melatonin with caution because the combination might amplify the effects. 

Is A Melatonin Supplement Safer Than Other Sleeping Pills?

For some people, melatonin can be just as effective at helping you fall asleep as prescription sleeping pills. But, you may wake feeling a little fresher. Prescription sleep aids can cause people to feel groggy and slow their reaction times the next day. Melatonin typically doesn’t have this effect. Melatonin should not be combined with a prescription drug without first consulting the prescribing provider.

If your doctor has prescribed you a medication, it’s for a reason. Never stop a prescription without discussing it with your doctor first. The information in this article is not intended to replace your doctor’s advice.

Prescription sleeping pills can be addictive. Melatonin is showing the potential to help get patients off of long-term prescription sleeping pills and offers a safer alternative

There is currently no evidence to suggest that you can develop a tolerance to melatonin. 

Will Melatonin Mess Up My Sleep Cycles If I Take It For Sleep? 

If you take too much melatonin, it may lead to daytime sleepiness. But this typically only happens if you take above the recommended dosage. 

What If I Can’t Take Melatonin But Need Help Sleeping? 

There are other ways to support health sleep that you can use with or without melatonin.

Non-drug Therapies Are Generally The Safest Solution To Poor Sleep.

All drugs and supplements carry a small risk of allergic reaction or side effects. If you have a long-term sleep disturbance, it’s best to look to non-drug alternatives to help you sleep. Some practices that might help include:

  • Cognitive behavioral therapy
  • White noise
  • Aromatherapy 
  • Meditation
  • Light therapy

Good Sleep Hygiene Is Important For Good Sleep

Good sleep hygiene means having healthy routines around sleep. Here are a few suggestions.

  • Sleep in a dark room (no night lights)
  • Avoid screens an hour before bed
  • Put a blue light filter on your computer and phone to come on as the sun sets
  • Avoid alcohol before bed
  • Go to bed at the same time each night and get up at the same time each morning
  • Exercise regularly
  • Avoid food too close to bed

So Overall, Is Melatonin Bad To Take Every Night?

Short term, melatonin can help recalibrate your sleep cycles after an interruption such as jet lag. It can also help short term such as when you are losing sleep before a big event, or struggling through a run of a night shift. 

But, taking it long term is not advisable because we just don’t know what the long term effects will be. 

For long-term sleep difficulties, try relying on non-drug therapies and good sleep hygiene where you can. Work with your doctor to address the root cause of sleeplessness. 

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About The Author

Dr. Jolene Brighten

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Dr. Jolene Brighten, NMD, is a women’s hormone expert and prominent leader in women’s medicine. As a licensed naturopathic physician who is board certified in naturopathic endocrinology, she takes an integrative approach in her clinical practice. A fierce patient advocate and completely dedicated to uncovering the root cause of hormonal imbalances, Dr. Brighten empowers women worldwide to take control of their health and their hormones. She is the best selling author of Beyond the Pill and Healing Your Body Naturally After Childbirth. Dr. Brighten is an international speaker, clinical educator, medical advisor within the tech community, and considered a leading authority on women’s health. She is a member of the MindBodyGreen Collective and a faculty member for the American Academy of Anti Aging Medicine. Her work has been featured in the New York Post, Forbes, Cosmopolitan, Huffington Post, Bustle, The Guardian, Sports Illustrated, Elle, and ABC News. Read more about me here.