8 Things That Can Happen If You Take Melatonin Every Night

If you’ve ever had trouble sleeping, you might have heard that melatonin is a great natural sleep aid that can help you kick your insomnia. A friend might’ve recommended it to you, or maybe even your doctor told you to take it to help you sleep. But is it really safe, or are there consequences of taking melatonin every night?

"Melatonin is not a sleep initiator, it's a sleep regulator, and there's a big difference there," clinical psychologist and sleep doctor Dr. Michael J. Breus, tells Bustle. "So melatonin doesn't make me fall asleep, but melatonin tells my body it's bedtime. Those turn out to be two completely different processes in the brain. Both have to be in sync in order for you to be able to fall asleep."

Melatonin is a naturally occurring hormone that regulates the body’s sleep-wake cycle, according to Mayo Clinic. But melatonin is also available as supplements, typically as oral tablets, says Mayo Clinic, which some people take to treat certain sleep disorders, such as insomnia, jet lag, or shift work disorder. Unlike a lot of over-the-counter sleep medications on the market, you’re less likely to become dependent on melatonin, experience a decreased response to its effects, or experience any side effects, according to Mayo Clinic.

Dr. Breus says, however, that many people take melatonin incorrectly, and that can increase the likelihood of side effects in the short term. "The appropriate dose [for melatonin] is somewhere between a half and one and a half milligrams ... If you look around, almost nobody sells it at that. They sell it at three, five, even 10 milligrams. So most people are actually overdosing themselves on melatonin," which can lead to side effects like headaches, dizziness, nausea, and drowsiness, says Mayo Clinic. Further, Dr. Breus says most people take melatonin when they're already having trouble sleeping, but that the most pill forms of melatonin take around 90 minutes to have any effect. "You couldn't pick a worse time to take melatonin [than] at 2:00 in the morning."

There’s a risk of side effects for pretty much any medication or supplement you take, so for melatonin to come with its own laundry list of side effects is nothing really out of the ordinary. But both Mayo Clinic and the National Center for Complementary and Integrative Health say there haven’t been enough studies conducted to know how safe it is to take melatonin on a long-term basis, and what’s “long-term” is up for debate.

According to Medical News Today, there are some clinical trials that have shown that it’s safe to take melatonin for up to three months. A 2018 study published in the journal Healthcare that followed children under 12 into young adulthood said there might be a connection between melatonin therapy and delayed puberty onset, but that connection was "inconclusive." Overall, the researchers said the results showed melatonin therapy “appeared to be safe” after an average of seven years of treatment. And a 2013 study published in the British Journal of Clinical Pharmacology found that the effects of melatonin simply started to wear off on people after about three months of use. Long story short: medical experts simply don’t know how safe it is to take melatonin for longer than three months at a time.

But even though melatonin might be safe to take in the short-term, there are still some things to consider before taking it to help you get a good night’s rest. Dr. Breus notes that if melatonin stops working after a day or two for you, it's more likely that the placebo effect is helping you sleep, and not the melatonin itself. According to Medical News Today, if you’re having trouble falling or staying asleep, it’s often because of a secondary cause, like an illness or a medical condition. That means if you’re taking something like melatonin for weeks on end, you could be covering up something more serious. Insomnia can be caused by all kinds of physical and psychological conditions, says Medical News Today, like depression, anxiety, congestive heart failure, sleep apnea, acid reflux, hormonal changes, Parkinson’s Disease, and more. The Sleep Foundation says it’s super important to understand what’s actually causing your sleep difficulties so you can treat the cause. Are you having a medical issue, is it a side effect of a medication, do you need to make a lifestyle change, is it something you’re eating, asks The Sleep Foundation.

It’s OK to try a natural sleep aid in the short-term, but remember that there are so many reasons behind why you could be having trouble sleeping. Finding the actual cause behind your sleep troubles might help you get to sleep even faster.