Is Taking Melatonin Regularly Safe? (Here's What Research Shows)

That familiar 2 AM ceiling-staring contest is becoming the nation's most unwanted nightly ritual. In response, melatonin supplement usage has more than quintupled in recent years, with over 5 million adults and 4 million children in the U.S. now taking it regularly to help with sleep issues.

But as this sleep aid becomes a nightly ritual for many, an important question emerges: Is taking melatonin regularly actually safe for long-term use?

A 2023 review in Neurology International examined melatonin’s long-term effects, quality concerns, and clinical considerations. So, what does the science really say? Let’s break down the findings and explore whether melatonin is safe for nightly use—and what natural alternatives might be worth considering.

The Melatonin Boom

Walk down any pharmacy aisle, and you'll spot dozens of melatonin products in various forms—gummies, tablets, liquids, and even sprays. According to research cited in the Neurology International review, melatonin use among American adults increased from just 0.4% in 1999 to over 2.1% by 2018. This growth has only accelerated, with a recent January 2025 market report valuing the global melatonin supplements market at USD 2.84 billion in 2024. The market is projected to grow at a compound annual growth rate of over 14.9% from 2025 to 2034, driven by increasing awareness of the importance and the growing prevalence of sleep disorders worldwide.

Why the surge? Our increasingly digital lifestyle, with screens emitting sleep-disrupting blue light at all hours, has contributed to widespread sleep problems. The stress and anxiety from the COVID-19 pandemic period created lasting changes in sleep habits for many, and even today, we're still seeing the ripple effects in sleep quality nationwide.

Unlike countries such as the UK, Japan, Australia, and most of Europe, where melatonin requires a prescription, the U.S. classifies it as a dietary supplement available over the counter by the Food and Drug Administration (FDA). This classification means much less regulatory oversight—a detail that becomes important when we consider safety.

How Natural Melatonin Works in Your Body

Melatonin is a natural hormone produced by the pineal gland in your brain, though smaller amounts are made in other tissues, including your gut, bone marrow, and even your retinas.

Think of melatonin as your body's timekeeper. During daylight hours, levels remain low. As evening approaches, your melatonin begins rising about two hours before your typical bedtime, helping signal your body that it's time to sleep. These levels remain elevated throughout the night and then drop rapidly about an hour before your usual wake time.

Beyond sleep, melatonin plays crucial roles in immune system function and acts as an antioxidant in your body, helping fight cellular damage. As we age, our natural melatonin production decreases significantly—part of why many older adults experience more sleep problems.

Quality Concerns with Store-Bought Supplements

One of the biggest safety issues with melatonin isn't necessarily the hormone itself but rather what you're actually getting in the bottle.

As noted in the Neurology International review, a Journal of Clinical Sleep Medicine study found that the actual melatonin content in commercial supplements varied wildly—ranging from 83% less to 478% more than what was listed on the label. Even more troubling, the researchers found that lot-to-lot variability of the same product could differ by as much as 465%.

About 26% of the tested products were also contaminated with serotonin, a neurotransmitter that can have significant effects on the body and potentially dangerous interactions with certain medications.

Also: HealthNews Warns of Dangers of Using Too Much Melatonin

This lack of standardization means that even if you're taking the same dose every night, you might be getting dramatically different amounts of melatonin—making both safety and effectiveness difficult to predict. That's partly why many consumers are turning to natural melatonin alternatives like Sip2Sleep®, which uses plant-based ingredients without synthetic hormones.

What Science Says About Effectiveness

When it comes to helping you fall asleep, the research shows melatonin does work—but perhaps not as dramatically as many hope. Meta-analyses cited in the review show that melatonin typically helps people fall asleep 1-30 minutes faster than without it, with the most significant benefits seen in people with delayed sleep phase syndrome.

For maintaining sleep throughout the night, immediate-release formulations often fall short, while sustained-release versions show more promise.

But what happens if you take melatonin and don't go to sleep? Taking melatonin and remaining awake won't cause severe harm, but you might experience drowsiness, impaired alertness, or dizziness. It's best to take melatonin only when you're ready for sleep and can dedicate 7-8 hours to rest.

Melatonin benefits include:

• Reduced time to fall asleep

• Improved sleep quality for some individuals

• Better sleep for people with autism spectrum disorder

• Potential cognitive protection in mild Alzheimer's disease

Certain populations seem to benefit more significantly from melatonin. The review highlights multiple studies showing that children with autism spectrum disorder experience decreased time to fall asleep, increased total sleep time, and improved daytime behaviors when taking melatonin regularly.

Research also suggests potential cognitive benefits in people with mild Alzheimer's disease, with a systematic review showing improved scores on cognitive tests. Scientists are currently exploring melatonin's neuroprotective properties for everything from concussion recovery to preventing cognitive decline.

Short-Term Side Effects

For most people, short-term melatonin use appears quite safe, with side effects that are typically mild and temporary. The most commonly reported issues include:

• Headache

• Daytime drowsiness or fatigue

• Dizziness

• Nausea or other digestive discomfort

• Vivid dreams

Interestingly, some studies analyzed in the review found no significant difference in the rate of these side effects between people taking melatonin versus those taking a placebo.

Also: Insomnia and Sleep Meds Linked with Dementia in New Study—Here’s an Alternative

However, people with certain conditions should exercise caution. Those with autoimmune disorders, depression, or hormone-sensitive conditions may want to consult their doctor before starting melatonin, as it can potentially affect hormonal balance.

Long-Term Safety Questions

While short-term use seems relatively benign, the research on long-term melatonin use is still developing. Many people ask, "Is it bad to take melatonin every night long-term?" The scientific consensus advises caution, as prolonged use has not been extensively studied.

When considering melatonin side effects long-term, research is limited, but several potential concerns have emerged:

• Hormonal effects and puberty timing: According to studies examined in the review, long-term melatonin might delay puberty in children, as melatonin levels naturally decrease during sexual maturation. While the evidence isn't conclusive, parents should discuss this potential risk with pediatricians.

• Fracture risk in older adults: A UK study referenced in the Neurology International review found that adults over 65 who took extended-release melatonin were 44% more likely to experience fractures than those who didn't. Researchers theorize this may be related to melatonin's effects on balance.

• Balance and coordination: The review cites research showing that melatonin can significantly impair balance in older adults about an hour after taking it, though cognitive function remains unaffected. This suggests caution when getting up during the night after taking melatonin.

• Seizure effects: The evidence here is mixed. Some studies in the review suggest melatonin may increase seizure activity in children with neurological deficits, while others show it actually decreases seizures when used to improve sleep.

• Mental health impacts: At normal doses (0.5-6mg daily), melatonin doesn't appear to worsen depression or other mood disorders. However, extremely high doses (250-1200mg) have been shown to potentially exacerbate symptoms in some individuals.

Drug Interactions Worth Noting

Melatonin can interact with several medications, making it important to consult with your healthcare provider if you're on any of these:

• Blood thinners like warfarin, as melatonin may affect clotting factors.

• Blood pressure medications, particularly extended-release nifedipine.

• Immunosuppressants used after organ transplants.

• Sedatives or sleep medications like zolpidem (Ambien), which may cause increased sedation when combined with melatonin.

• Some antidepressants, particularly those that affect serotonin levels.

Also: There Might Be More to Your Melatonin Than You Think—Here’s an Alternative

Even seemingly innocent combinations can pose risks. For example, melatonin taken with caffeine can result in reduced effectiveness, while alcohol can increase sedation and potentially affect the liver's metabolism of melatonin.

Finding the Right Dose

The optimal dose of melatonin hasn't been clearly established, but research increasingly suggests that less may be more effective. Is it safe to take 10 mg of melatonin every night? While many over-the-counter products contain 5-10mg per dose, studies highlighted in the review increasingly indicate that smaller doses (around 0.5-1mg and definitely below 5 mg) are safer and just as effective for most people.

For most adults, sleep experts recommend starting with the lowest possible dose (0.5-1mg) and only increasing it if needed. The timing matters too—immediate-release forms should be taken 30-60 minutes before bedtime, while extended-release versions can be taken 1-2 hours before.

Also: What Happens to Your Body When You Take Melatonin Every Night

Some people ask, "Can I take melatonin at 3 am?" While it's possible, melatonin is most effective when taken before your usual bedtime. Taking melatonin too late at night can disrupt your circadian rhythm, causing increased daytime grogginess.

For older adults, who may metabolize melatonin more slowly, starting with even lower doses (0.1-0.5mg) may be prudent to avoid morning grogginess.

If dosing melatonin feels overwhelming or you're experiencing side effects, natural melatonin-free alternatives like Sip2Sleep® could be an ideal solution—providing consistent sleep support without worries about hormonal disruption or dependency.

Melatonin Alternatives and Natural Sleep Aids

If you're concerned about the safety or quality issues associated with synthetic melatonin supplements, several natural alternatives can support healthy sleep patterns without the potential downsides.

Plant-based compounds with strong research support include:

• Montmorency tart cherry: Research published in the European Journal of Nutrition shows this fruit is a natural source of both melatonin and tryptophan (which your body uses to make melatonin). Unlike synthetic options, tart cherry provides these sleep-supporting compounds in their natural matrix alongside beneficial antioxidants that support immune function.

• Rafuma leaf extract: Studies show this plant extract naturally increases serotonin and GABA levels, helping calm the mind and promote relaxation. Unlike pharmaceutical sleep aids, it works gently with your body's natural processes rather than forcing sleep.

Unlike synthetic melatonin supplements, Sip2Sleep® utilizes these natural ingredients—Montmorency Tart Cherry and Rafuma Leaf—both shown by research to gently improve sleep quality and relaxation without hormone-related side effects. Taken under your tongue, it enters your system quickly and efficiently compared to traditional capsules. By working with your body's own sleep-wake cycle instead of overwhelming it with high doses of synthetic hormones, Sip2Sleep® provides a more balanced approach to better rest without the melatonin side effects that concern many users.

Also: Can't Sleep? Discover Why Sip2Sleep® Works Better Than Melatonin

Complementing these natural sleep aids with good sleep habits—like maintaining a consistent sleep schedule, limiting screen time before bed, and creating a cool, dark sleep environment—can further enhance their effectiveness.

The Bottom Line on Melatonin Safety

So, is taking melatonin regularly safe? Based on current research, melatonin appears relatively safe at low to moderate doses (5mg or less) for most adults in the short term. However, the long-term effects still warrant additional investigation, and quality control issues remain significant.

If you're considering melatonin for regular use, keep these guidelines in mind:

• Start with the lowest possible dose (0.5-1mg for most adults).

• Choose reputable brands that undergo third-party testing.

• Talk to your healthcare provider if you're on other medications.

• Be especially cautious with children, teenagers, and older adults.

• Consider natural alternatives that provide sleep support without synthetic hormones.

While the occasional melatonin supplement might help you through jet lag or a particularly stressful week, relying on it as a nightly solution requires careful consideration of both the known and unknown risks. For many people, natural plant-based alternatives may offer a gentler, more holistic approach to supporting healthy sleep patterns over the long term.

If you're looking for a safer long-term alternative to melatonin supplements, consider exploring melatonin-free sleep aids such as Sip2Sleep®. Backed by science and thoughtfully designed for long-term sleep health, Sip2Sleep® offers peace of mind and improved sleep without synthetic melatonin.

Also: 5 Tips for Using Sip2Sleep® Before Bed

Remember, good sleep isn't just about what you take before bed—it's about creating the conditions that allow your body's natural sleep processes to work effectively. Finding the right support for your unique sleep needs might take some experimentation, but the reward of truly restorative rest is well worth the effort.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare provider before starting any supplement regimen.

References:

Givler, D.; Givler, A.; Luther, P.M.; Wenger, D.M.; Ahmadzadeh, S.; Shekoohi, S.; Edinoff, A.N.; Dorius, B.K.; Jean Baptiste, C.; Cornett, E.M.; et al. Chronic Administration of Melatonin: Physiological and Clinical Considerations. Neurol. Int. 2023, 15, 518-533. https://doi.org/10.3390/neurolint15010031