Melatonin is one of the most popular supplements for sleep. It’s cheap and effective. But is it safe? That’s what we’ll investigate in this article based on medical research.
We will analyze whether melatonin is safe for adults, children, pregnant women and other groups in separate sections.
Does Melatonin Supplementation Impact Natural Production?
One of the most common questions patients ask is whether melatonin supplementation can affect their natural production of melatonin. Our bodies produce melatonin to regulate the sleep-wake cycle, so if natural production shuts down due to oral use that would be dangerous.
Thankfully, medical research has proven that taking melatonin supplements does not impact our body's production of the hormone. The above-linked medical study found that even doses as high as 50 milligrams (mg) daily, which is significantly higher than most over-the-counter (OTC) melatonin products, had no impact on the amount of melatonin secreted by the body.
Is Melatonin Safe for Adults?
Melatonin is one of the safest OTC supplements, and has no proven toxicity level. Researchers couldn’t even find an LD-50 dose (lethal dose for 50% of subjects) in animal studies which is uncommon, and shows how safe this compound is even at doses many factors higher than you’d get in a supplement.
We can conclude that melatonin is safe and non-toxic for adults, but there are two groups that may wish to avoid it: men seeking to have a child in the near future, and people with blood sugar issues.
One medical study found that some men taking a 3 mg dose of melatonin had negative impacts on their semen quality. This study hasn’t been replicated and only had 8 participants, so we don’t think it’s conclusive.
That being said, it may be worth speaking with your doctor before supplementing melatonin if you’re a man looking to have a child in the near future.
Another clinical trial found that melatonin supplementation negatively impacted glucose tolerance. Participants had increased blood sugar response to glucose after taking melatonin, so patients who are diabetic or pre-diabetic may want to speak with their doctor about monitoring their glucose in response to meals post-melatonin.
Is Melatonin Safe for Children?
Because melatonin has such a safe biochemical profile, there is actually a significant amount of research on it with child participants.
A medical review of melatonin’s use for sleep disorders in children concluded that it was safe in otherwise healthy children, but should be avoided in children with immune disorders due to how melatonin interacts with the immune system.
Another long-term study on melatonin’s safety for children found that its use entailed “no safety concerns regarding serious adverse events” and the average time to follow up was 3.7 years, meaning the children had been taking the melatonin for a long time in most cases.
A third review of melatonin as a sleep aid for children found “that significant side effects of melatonin in children have not been reported. This review analyzed over 100 individual studies on the topic.
Overall, we can conclude that melatonin seems safe for healthy children but may be risky for children with chronic conditions like immune disorders. We definitely recommend that parents speak with a pediatrician prior to use of OTC medications for their child, since the risk of any adverse reaction is higher to a developing body than to an adult.
How Much Melatonin is Safe?
While some melatonin products contain as low as 300 micrograms (mcg), there are plenty of OTC melatonin supplements that contain 20 mg or higher.
Many consumers are confused about how much melatonin they can safely take, especially if they have significant sleep issues that may be resolved with higher doses of melatonin than average.
While there exist studies on melatonin for sleep with doses as high as 20 mg, we generally recommend a dose of 10 mg or below.
Doses as high as 100 mg have been used on patients with no adverse effects, so even doses that high are likely safe, but we haven’t come across much data suggesting that higher doses are more effective beyond a 10 mg limit.
Interestingly, a woman actually tried to overdose intentionally on melatonin by taking 100 mg at one time, but the only effects she experienced were drowsiness and a slight pulse elevation, according to Poison Control.
Is Melatonin Safe During Pregnancy?
Pregnant women are aware that they must be more cautious about supplements they ingest which can impact the health and development of their child.
A medical review of melatonin use during pregnancy found no adverse effects, and even suggested that melatonin supplementation may protect the child from adverse health outcomes later in life such as cardiovascular and neurological diseases. However, the data is much too early to state this as a fact; it’s just an area with promise that should be researched further.
We believe that due to the safety risks, no supplement should be recommended across-the-board to pregnant women, and that pregnant women should speak with their doctor about whether melatonin supplementation may be safe for them.
Is It Safe To Take Melatonin Every Night?
As we’ve established in prior-linked research, melatonin has a fantastic safety profile and is safe for adults in doses up to 100 mg, but ideally at or below 10 mg as an effective dose.
Often, patients are curious about whether melatonin has any addiction potential. They worry that if they take melatonin every night, they may become dependent on it to sleep in the future.
Fortunately, there is no evidence of tolerance or addiction potential based on a thorough medical review. This lack of tolerance effect held for all melatonin doses examined.
This makes sense logically, since as we established previously, melatonin supplementation doesn’t affect the body’s production of melatonin. So even if a patient were to take a relatively high dose of melatonin like 20 mg, their body would still be producing the same amount of melatonin as usual the day they stopped taking the supplement.
Which Brand of Melatonin Do You Recommend?
If you’ve read to this point in the article, you’re probably curious about which type and brand of melatonin we recommend.
We generally don’t recommend specific brands to remain unbiased, and because we have no affiliations or partnerships with any brands.
We do recommend melatonin capsules over melatonin gummies. Capsule products typically have healthier inactive ingredients. We recommend looking for a melatonin capsule product with no harmful preservatives or fillers.
We don’t recommend melatonin gummies because these almost always contain added sugar, which is harmful to human health in excess. There’s no point in taking a health supplement with an additive that’s unhealthy.