How much melatonin should i take
Pro Research Analysisby 
Searched over 200M research papers
Optimal Melatonin Dosage: A Comprehensive Review
Introduction to Melatonin and Its Uses
Melatonin is a hormone that plays a crucial role in regulating the circadian rhythm, which is the body's internal clock that dictates sleep-wake cycles. As people age, their natural melatonin levels tend to decline, leading to sleep disorders and other circadian rhythm-related issues. Melatonin supplements are often used to address these problems, but determining the optimal dosage can be challenging due to varying individual needs and responses.
Recommended Dosage for Older Adults
Low-Dose Melatonin for Mimicking Natural Rhythms
Research suggests that older adults should use the lowest possible dose of immediate-release melatonin to best mimic the natural circadian rhythm and avoid prolonged, supra-physiological blood levels1. This approach helps in maintaining melatonin levels within a physiological range, thereby reducing the risk of potential side effects.
Effective Dosage Range
Clinical studies have evaluated a variety of melatonin doses, ranging from 0.5 mg to 10 mg, and their effects on sleep in older adults. The results indicate that doses between 1 mg and 6 mg are generally effective for improving sleep outcomes3. However, further studies are needed to pinpoint the optimal minimum effective dose.
Dosage for Specific Conditions
Sleep Disorders
For treating sleep disorders, melatonin doses as low as 0.3 mg to 1 mg taken 2-4 hours before bedtime have been shown to facilitate sleep onset without altering sleep architecture or causing morning hangover effects9. Higher doses, such as 75 mg, have also been used in studies, but these are considered supraphysiologic and are not typically recommended for general use10.
Cardiometabolic Health
In diabetic patients with coronary heart disease, a higher dose of 10 mg of melatonin daily for 12 weeks has been found to significantly improve various biomarkers of oxidative stress and cardio-metabolic risk5. This suggests that higher doses may be beneficial for specific health conditions beyond sleep regulation.
Timing of Administration
The timing of melatonin administration is crucial for its effectiveness. Studies have shown that taking 0.5 mg of melatonin in the afternoon, 2-4 hours before the dim light melatonin onset (DLMO), or 9-11 hours before sleep midpoint, results in maximum phase advances2. This timing helps in aligning the body's internal clock with the desired sleep schedule.
Safety and Adverse Effects
General Safety
Melatonin is generally regarded as safe and well-tolerated, with few adverse events reported. Common side effects include daytime sleepiness, headache, dizziness, and hypothermia, but these are typically mild and resolve spontaneously7. Long-term safety data are limited, so caution is advised for extended use.
Special Populations
In children, especially those with conditions like autism spectrum disorder, doses up to 10.5 mg have been used without significant harm, although the British National Formulary recommends a maximum of 10 mg daily8. For critically ill patients with sepsis, doses up to 20 mg have been found to be well-tolerated, although higher doses may lead to saturation and reduced effectiveness6.
Conclusion
The optimal melatonin dosage varies depending on the individual's age, health condition, and specific needs. For older adults, a low dose of 1-6 mg is generally effective for improving sleep, while higher doses may be beneficial for specific health conditions like diabetes and coronary heart disease. The timing of administration is also crucial for maximizing benefits. Overall, melatonin is safe and well-tolerated, but long-term safety data are limited, and further research is needed to establish the optimal dosing guidelines.
Sources and full results
Most relevant research papers on this topic
Optimal Dosages for Melatonin Supplementation Therapy in Older Adults: A Systematic Review of Current Literature
In older adults, the lowest possible dose of immediate-release melatonin is recommended to best mimic the normal physiological circadian rhythm and avoid prolonged supra-physiological blood levels.
Systematic Review
Rigorous Journal
Highly CitedHuman phase response curves to three days of daily melatonin: 0.5 mg versus 3.0 mg.
Optimal administration time for 0.5 mg melatonin is later, 2-4 hours before the DLMO or 9-11 hours before sleep midpoint, yielding similarly sized advances and delays when both doses are given at their optimal time.
Rigorous JournalHighly CitedOptimal Melatonin Dose in Older Adults: A Clinical Review of the Literature.
Melatonin doses between 1 mg and 6 mg are effective for improving sleep in older adults, but further studies are needed to determine the optimal minimum effective dose.
Systematic ReviewMelatonin pharmacokinetics following two different oral surge‐sustained release doses in older adults
Melatonin pharmacokinetics remain linear in older adults, with both low-dose and high-dose doses maintaining elevated levels beyond the typical sleep period.
RCTHighly CitedMelatonin administration lowers biomarkers of oxidative stress and cardio-metabolic risk in type 2 diabetic patients with coronary heart disease: A randomized, double-blind, placebo-controlled trial.
Melatonin supplementation significantly improves metabolic health and reduces oxidative stress in type 2 diabetic patients with coronary heart disease.
RCT
Very Rigorous JournalHighly CitedDose assessment of melatonin in sepsis (DAMSEL2) study: Pharmacokinetics of two doses of oral melatonin in patients with sepsis
20 mg of oral melatonin is a suitable dose for patients with sepsis, as it is well-tolerated and well-reported without adverse events.
RCTAdverse Events Associated with Melatonin for the Treatment of Primary or Secondary Sleep Disorders: A Systematic Review
Melatonin treatment for sleep disorders is generally safe and well-tolerated, with few serious adverse events reported.
Systematic ReviewRigorous JournalHighly CitedMelatonin for sleep disorders in children
A dose of 10.5 mg daily for a 612-year-old child with autistic spectrum disorder is unlikely to cause significant harm, as melatonin has not been shown to cause severe adverse effects at a wide range of doses.
Effects of low oral doses of melatonin, given 2-4 hours before habitual bedtime, on sleep in normal young humans.
Low oral doses of melatonin, given 2-4 hours before bedtime, can facilitate sleep onset and stage 2 sleep without significantly altering sleep architecture in normal young adults.
RCTHighly CitedThe effects of exogenous melatonin on the total sleep time and daytime alertness of chronic insomniacs: A preliminary study
Exogenous melatonin significantly increases total sleep time and daytime alertness in chronic insomniacs, but may not significantly affect well-being.
RCTHighly Cited