Is it safe to take melatonin every night
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Safety of Taking Melatonin Every Night: A Comprehensive Review
Introduction to Melatonin and Its Uses
Melatonin is a hormone produced by the pineal gland that regulates sleep and circadian rhythms. It is commonly used as a supplement to address sleep disorders, jet lag, and other conditions. However, the safety of nightly melatonin use remains a topic of interest and research.
Feasibility and Safety in Nightshift Workers
A study involving doctors and nurses working nightshifts found that melatonin administration was feasible and acceptable, with negligible side effects. Participants who took 6 mg of slow-release melatonin showed improved attention and concentration tasks, suggesting potential benefits for nightshift workers . This indicates that melatonin can be safely used in specific occupational settings without significant adverse effects.
Impact on Sleep Quality and Cardiometabolic Health
Research on women aged 55 and older with insomnia showed that taking 2 mg of melatonin nightly for six weeks improved sleep quality but did not significantly affect arterial stiffness, mitochondrial DNA, or insulin resistance . This suggests that while melatonin can enhance sleep, its benefits on broader health parameters may be limited.
Adaptation to Night Shifts
A study on emergency medical services personnel working rotating night shifts found no significant differences in sleep quality, mood, or workload ratings between those taking melatonin and those taking a placebo. Adverse effects were rare, with only one participant reporting prolonged sedation . This indicates that melatonin may not provide substantial benefits for circadian rhythm adaptation in all nightshift workers.
Safety of Higher Doses
A systematic review and meta-analysis of high-dose melatonin (≥10 mg) found that while melatonin did not increase serious adverse events or withdrawals due to adverse events, it did increase the risk of mild side effects such as drowsiness, headache, and dizziness . This suggests that higher doses of melatonin are generally safe but may lead to minor discomforts.
Adverse Events in Long-Term Use
A systematic review of melatonin for treating sleep disorders reported that the most common adverse events were daytime sleepiness, headache, dizziness, and hypothermia. Serious adverse events were rare, and most side effects resolved spontaneously or upon discontinuation of melatonin . This supports the notion that melatonin is safe for short-term use, but long-term safety data are limited.
Effects on Nocturia and Hypertension
In patients with multiple sclerosis, melatonin did not significantly reduce nocturia episodes or improve sleep quality compared to a placebo . However, a meta-analysis on hypertension found that controlled-release melatonin reduced asleep systolic blood pressure and improved sleep quality without significant side effects . These findings suggest that melatonin may have specific benefits for certain conditions but not others.
Insulin Sensitivity and Diabetes
A study on patients with type 2 diabetes found that three months of 10 mg melatonin treatment decreased insulin sensitivity by 12%, indicating a potential negative impact on glucose metabolism . This highlights the need for caution when using melatonin in individuals with metabolic disorders.
Conclusion
Overall, melatonin appears to be a safe supplement for nightly use in the short term, with benefits for sleep quality and specific conditions like hypertension. However, higher doses may lead to mild side effects, and long-term safety data are limited. Individuals with metabolic disorders should use melatonin cautiously. Further research is needed to fully understand the long-term safety and broader health impacts of nightly melatonin use.
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