Long term melatonin use raises safety concerns as its popularity continues to grow. The last 15 years have seen a dramatic rise in melatonin consumption. This piece explores what science tells us about whether melatonin is bad for you in long term and the real health risks of continued use.
Is it safe to take melatonin every night for a long time?
Melatonin is generally considered safe for long-term use in healthy adults when taken at low to moderate doses. Unlike many sleep medications, it does not appear to cause dependence, withdrawal or tolerance.
However, prolonged use may lead to mild side effects in some people, such as daytime drowsiness, vivid dreams or hormonal interference, especially in children and adolescents. Research on long term use is still ongoing, but current evidence suggests that melatonin is well-tolerated if used responsibly and under medical guidance.
What is melatonin and how does it work?
Melatonin is a key hormone that regulates sleep and acts as the body’s natural timekeeper. Our pineal gland, deep in the brain, makes this powerful chemical messenger mainly in response to darkness. The basic role of melatonin in our daily rhythms helps us understand its biological importance.
Melatonin’s role in the circadian rhythm
The brain uses melatonin as its main signal of darkness to control our 24-hour internal clock (circadian rhythm). Our melatonin levels start rising in the evening as it gets dark and usually peak around 3-4 AM. The hormone doesn’t make us sleep directly but creates the right conditions for sleep to happen.
Our body follows a steady pattern. Melatonin starts increasing about 2 hours before our usual bedtime to prepare for rest. This natural increase matches up with our body temperature dropping and sleep becoming more likely. Melatonin stays in our bloodstream all night with a half-life of about 40 minutes.
Studies show that blue light from electronic devices can block melatonin production. So this can throw off normal sleep patterns and lead to insomnia or delayed sleep.
How melatonin supplements differ from natural production
Natural (endogenous) melatonin comes from our pineal gland, while supplements use synthetic melatonin made in labs. These synthetic versions are similar to natural melatonin but enter our bloodstream differently.
Our body absorbs supplemental melatonin faster after we take it. It first passes through the liver and reaches its highest blood levels between 20 minutes and 2 hours later. But these supplements can vary a lot in what they actually contain. Studies show they might have up to 478% more melatonin than labeled.
Our body releases melatonin slowly throughout the night, but supplements create one quick spike that drops off fast. Natural production also adjusts to environmental signals, while supplements give us the same amount at the same time.
Why melatonin use has increased globally
More people are taking melatonin now than ever before. Research show that american adults using it jumped from 0.4% in 1999-2000 to 2.1% in 2017-2018. On top of that, high-dose melatonin use (over 5mg daily) more than tripled from 0.08% of people in 2005-2006 to 0.28% in 2017-2018.
This trend has many reasons. Our natural melatonin production usually drops as we age, which makes older adults turn to supplements. Modern life with screen time and irregular schedules disrupts our natural melatonin cycles. People are also getting more interested in melatonin’s other benefits beyond sleep, like its antioxidant and anti-inflammatory properties.
Short term benefits and common uses
Melatonin supplements work well for specific short term needs, especially sleep issues and anxiety. Research keeps showing its benefits for certain conditions with proper usage.
Jet lag and circadian rhythm disorders
Melatonin reduces jet lag symptoms by a lot when we cross five or more time zones. Studies show that melatonin lowers jet lag severity and cuts recovery time by 1-1.5 days after long flights. We should take melatonin at our destination’s normal bedtime for up to five nights to get the best results. A review of 10 studies found that melatonin helped reduce jet lag in all but one of these studies when taken near local bedtime. The benefits are strongest for eastward travel, though it helps with westward trips too.
Sleep onset insomnia in older adults
Natural melatonin production often drops as people age, which makes supplements work better for older adults. Studies show melatonin cuts down the time to fall asleep by 9 minutes compared to placebo. Older adults over 55 who took prolonged release melatonin (2mg nightly) fell asleep 15.4 minutes faster after three weeks, according to research.
Use in children with neurodevelopmental disorders
Sleep problems often affect children with neurodevelopmental disorders. The largest longitudinal study of 13 randomized controlled trials (682 participants) showed melatonin improved total sleep time by 48.26 minutes more than placebo. Children also fell asleep much faster, with a 28.97-minute reduction in sleep onset time.
Anxiety before medical procedures
Melatonin helps reduce anxiety before surgery. A review of 18 studies (1,264 participants) showed it lowered preoperative anxiety by 11.69 points on a 100mm visual analog scale versus placebo. It also cut down immediate postoperative anxiety by 5.04 points. The results match standard benzodiazepine treatments for surgical anxiety but with fewer side effects like drowsiness or dizziness.
What science says about long term use
Scientific research shows a mixed picture of long term melatonin supplementation with both promising results and areas that need more research. This becomes even more crucial as more people worldwide start taking melatonin supplements.
Does melatonin decrease natural production?
Research shows that taking melatonin supplements doesn’t suppress our body’s natural melatonin production or cause rebound insomnia. Studies haven’t found any withdrawal symptoms when people stop taking melatonin. This makes melatonin different from many sleep medications that can make us dependent if we use them for too long.
Hormonal effects and puberty concerns
Scientists have questions about how melatonin and sexual development connect, especially for children and teenagers who take it long term. Natural melatonin levels drop by about 80% from childhood through adolescence. Some researchers think this drop might affect when puberty starts, since melatonin can stop gonadotropin-releasing hormone (GnRH) production in animal studies.
Keep in mind that we don’t have clear clinical evidence about how melatonin affects human sexual development.
Mood changes, vivid dreams and fatigue
People who take melatonin for long periods sometimes notice changes in their mood. They might feel temporarily depressed, slightly anxious, irritable or less alert. Dementia patients who take melatonin often get worse mood ratings from their caregivers.
Many users report having vivid dreams. If we feel too drowsy after taking melatonin, we might be taking too much or at the wrong time.
Drug interactions and contraindications
Melatonin can interact with many medications and affect how well they work or how safe they are. The biggest concerns include:
- Anticoagulants: we might bleed more easily;
- Anticonvulsants: seizures might happen more often, especially in children with neurological disabilities;
- Blood pressure medications: our blood pressure control might get worse;
- Immunosuppressants: his could affect medications after organ transplants;
- Diabetes medications: our blood sugar levels might change.
Impact on bone health and fracture risk
Melatonin has a complex relationship with bone health. Research shows that prescribed melatonin increased fracture risk by a lot even after accounting for other factors. Yet some studies suggest melatonin might actually help bone health.
Women’s melatonin production drops during menopause, which scientists link to post-menopausal osteoporosis. Night shift workers, whose normal melatonin production gets disrupted, face a higher risk of wrist and hip fractures if they’re post-menopausal women.
Cognitive effects and aging
Long term melatonin use might help brain function. Alzheimer’s patients who took melatonin for more than 12 weeks showed better scores on mini-mental state examinations, according to studies. These benefits worked best for people with mild Alzheimer’s disease.
Our natural melatonin production drops as we age, 80-year-olds make 10 times less melatonin than teenagers. This drop reduces antioxidant effects, anti-inflammatory benefits and how well mitochondria work. Taking melatonin supplements might work as a powerful antioxidant and anti-aging agent by fixing mitochondrial membrane permeability and boosting antioxidant enzymes.
How to use melatonin safely and alternatives to consider
The right way to take melatonin depends on proper dosing, timing and our health background based on what science tells us today. We can use melatonin as a short-term sleep aid safely and effectively by following the right guidelines.
When to avoid melatonin supplementation
These groups should be careful about taking melatonin or avoid it completely:
- Pregnant or nursing mothers;
- People who have autoimmune conditions;
- Those with seizure disorders;
- People with depression;
- Babies and toddlers under 2.
Melatonin can interact with many medications like blood thinners, seizure medications, immunosuppressants, diabetes drugs and some antidepressants. People with blood sugar issues or blood pressure concerns should talk to their doctor before taking melatonin.
Alternatives: magnesium, L-theanine, CBT-I
Magnesium proves helpful for better sleep, particularly in older adults who can’t sleep well. This mineral naturally exists in whole grains, avocados and nuts. It helps control GABA, a brain chemical that makes us feel less alert.
L-theanine, a natural compound found in tea, might help us sleep better without making us groggy during the day. Research suggests taking 200mg of l-theanine before bed may support improved sleep quality through anxiolysis rather than sedation.
CBT-I remains the best non-drug treatment option. It tackles the root causes of sleep problems instead of just treating the symptoms.
Sleep hygiene practices that support melatonin
Good sleep habits make melatonin work better:
- Go to bed and wake up at the same time daily, even on weekends;
- Keep our bedroom around 67°F to help lower our body temperature;
- Stay away from screens an hour before bed to reduce blue light exposure;
- Make our bedroom completely dark;
- Skip caffeine and alcohol since they mess with our natural melatonin production.
Melatonin helps manage sleep problems effectively, but we should talk to our healthcare provider about long term use. This becomes especially important if we take other medications or belong to vulnerable groups. Scientific evidence suggests melatonin remains safe for most adults when used correctly.
