Melatonin: How it Helps you Sleep and Other Benefits
Melatonin is a natural antioxidant compound, known chemically as N-acetyl-5-methoxytryptamine, that is present in humans, animals, plants and microbes. Small amounts are found in vegetables, grains and meats, yet no foods have been proven to elevate melatonin levels. Melatonin regulates circadian rhythms, which is the body’s natural wake and sleep cycle that works in combination with daylight and nighttime hours. Synthetic melatonin is available in supplement form, and typically used to promote sleep and alleviate sleep disorders. However, research studies are finding that it is highly effective in treating other physiological disorders associated with melatonin deficiencies, such as seasonal affective disorder (SAD), immunological disorders, anxiety and stress, depression, cancer, cardiovascular disease, headaches, reproductive difficulties, high blood pressure and obesity.
As with other vitamin and nutritional supplements, melatonin is not regulated by the Food and Drug Administration (FDA) for effectiveness, safety or purity. Therefore, health supplements should be purchased from a reliable source. Seek the advice of a medical physician before administering melatonin to children, as doses between 1 and 5 mg may cause seizures. Dosage recommendations for adults are 1 to 3 mg one hour before bedtime or if ineffective, 5 to 6 mg. Begin with the smallest dose and increase the amount, only if necessary.
Melatonin is a hormone secreted and synthesized by the pineal gland, which is an organ 1 cm in length and in the shape of a pinecone, located near the center of the brain on the midline. It is attached to the posterior end of the third ventricle. The secretion of melatonin is stimulated by nerves in the eyes. Therefore, melatonin levels fluctuate throughout the day in response to light, and are activated by melatonin receptors in the brain, while remaining secretions are absorbed by the body as powerful antioxidants.
Melatonin communicates information about light in the environment to numerous places throughout the body. Fundamentally, melatonin regulates the body’s biological rhythms and significantly effects reproductive functions. Researchers at Yale University discovered melatonin’s connection to sleep and hormonal stimulations in 1958, at which time, possible links to its effects on cancer were found.
- Melatonin-What is it? – The website provides a description of melatonin’s physiological effects on the body, its availability in supplement form and its ability to prevent cancer cells from spreading.
- Melatonin History and Evidence – The American Cancer Society discusses the research evidence related to melatonin’s effectiveness in slowing or stopping the growth of cancerous cells in the body.
- Melatonin: The Myths and Facts – Vanderbilt University provides a description of what melatonin is, as well as its effectiveness in treating jet lag, sleeping difficulties, and sleep and age-related disorders.
- Melatonin and Sleep Disorders – An explanation of how melatonin works to induce sleep and how it regulates the body’s sleep patterns, provided by Weill Cornell Medical College. The site also discusses important drug interactions of taking melatonin supplements with other medications.
- Melatonin Overview and Uses – The University of Maryland Medical Center supplies an overview of what melatonin is, in addition to its effects on the body and use as a supplement for insomnia, menopause, withdrawal symptoms from benzodiazepines, breast cancer, ADHD and fibromyalgia. The website also provides dosage instructions and potential side effects.
- Melatonin Deficiency and Excess – The Association for the Advancement of Restorative Medicine (AARM) describes the types of disorders associated with melatonin-related individuals that have melatonin-related deficiencies and excesses.
Biological Effects and Contraindications
Biologically, melatonin regulates the body’s 24-hour circadian rhythms and promotes natural sleep patterns by acting as the body’s internal clock. As daylight decreases and it becomes dark, impulses in the brain activate the pineal gland, and it secretes melatonin so that the body begins to feel more relaxed and sleepy. As daylight comes, melatonin decreases, which makes the body wake for activity. Working late at night under bright lights can interfere with the body’s internal clock, and result in deficiencies in melatonin production. Because melatonin is produced in response to light and circadian rhythms, those affected by seasonal affective disorder (SAD), in which the body produces too much melatonin, are likely to sleep too much, feel tired constantly and experience overwhelming depression. Although individuals with SAD have elevated levels of melatonin, some studies have shown that additional synthetic supplementation of the hormone alleviates symptoms by enabling the body to more efficiently regulate the hormone’s levels in response to circadian rhythms.
Adverse effects of melatonin use include headache, irritability, stomach cramps, decreased libido and reduced sperm count. It has also been found to affect the thyroid and adrenal cortex functions in some individuals, as well as worsen depression and cause excessive sleepiness. Some users report vivid dreams or nightmares. This is generally caused by modifications in sleep cycles, in which they may be awakening during rapid eye movement (REM) sleep, when dreams tend to be the most vivid. If any of these symptoms are experienced, a lower dose should be administered. Potential side effects and interactions have been indicated with certain medications, which include antidepressants, antipsychotics, blood pressure calcium channel blockers and beta blockers, benzodiazepines, anticoagulants and nonsteroidal anti-inflammatories (NSAIDS).
- Endocrine System – The biology department at Clermont College provides a thorough explanation of the role of the pineal gland play in producing melatonin in the brain, which promotes sleep.
- The Pineal Gland and Melatonin – Colorado State University illustrates how the pineal gland synthesizes and secretes melatonin through the use of graphic images and descriptions.
- Melatonin: A Sleep-Promoting Hormone (PDF) – A PDF of a chapter publication from the American Sleep Disorders Association and Sleep Research Society, which discusses the effects of melatonin on the sleep cycle and the body’s circadian rhythms.
- Melatonin Has Antioxidant Effects – A website that references several studies that indicate melatonin’s effectiveness in acting as an antioxidant and reducing oxidative stress.
- Melatonin-Principal Proposed and Other Uses – Information provided by New York University’s Langone Medical Center that explains the scientific evidence for supporting melatonin as a treatment for jet lag, shift work, insomnia, sleep problems in the elderly and children, fatigue, cancer, headaches, seasonal affective disorder (SAD) and dementia.
Use for Sleep Disorders
Melatonin has been studied as an effective treatment for various types of sleep disorders, such as general disruptions in circadian rhythms, insomnia and jet lag, as well as with children that have attention deficit hyperactivity disorder (ADHD) and autism. Circadian rhythm sleep disorders and insomnia are a result of an ineffective regulation of the body’s biological clock, and in which sleep patterns are disrupted. Therefore, taking a melatonin supplement approximately 30 to 90 minutes before bed initiates a rise in melatonin levels in the blood and operates as a mild hypnotic to induce sleep. Subsequently, melatonin supplementation regulates the body’s internal clock and balances circadian rhythms into a more natural pattern, which encourages sleep and promotes health and overall well-being. Since circadian rhythms are based on 24-hour cycles, jet lag, which oftentimes occurs when traveling across time zones, can lead to disruptions in sleep patterns.
Studies show that taking 5 mg of melatonin approximately 3 to 4 days prior to leaving for a flight, speeds recovery from jet lag and improves sleep quality. Melatonin use has proven beneficial for children afflicted with attention deficit disorder with regard to improving sleep, but shows no correlation with regard to alleviating the symptoms of ADHD. Research published by the Journal of Child Neurology revealed that between 44 and 83 percent of autistic children show an improvement in sleep patterns, such as faster onset of sleep and longer sleep durations when treated with melatonin supplements. Double-blind trials have also demonstrated its effectiveness for improving the sleep of individuals with asthma, diabetes, head injuries, schizophrenia, Parkinson's disease and Alzheimer’s disease, who generally have irregular circadian rhythms.
- Melatonin and Sleep – The National Sleep Foundation describes how sleep cycles are naturally regulated by light. The site also provides dosage advice for synthetic melatonin and its effectiveness in treating the symptoms of jet lag.
- Melatonin for Sleep Disturbances – A website that provides information on what melatonin is, circadian rhythms, melatonin’s function in sleep, recommended dosages for synthetic melatonin, possible side effects and contraindications with other medications.
- Melatonin for Treatment of Sleep Disorders – The U.S. Department of Health & Human Service’s Agency for Healthcare Research and Quality (AHRQ), provides an Evidence Report/Technology Assessment of melatonin’s effectiveness in treating individuals with various sleep disorders.
- Melatonin and Sleep Disorders – The website provides a succinct explanation of melatonin’s physiological effects on the body and its effects on sleep patterns, as well as dreams.
- Melatonin Shows Promise for Improving Sleep Problems in Children with Autism – The organization, Autism Speaks, provides information related to melatonin’s ability to improve the sleep patterns of autistic children.
- Melatonin and ADHD Children – A summary reference page regarding a study conducted to provide evidence for melatonin’s success in treating children that have ADHD, and who are taking stimulant medications for their condition.
Other Uses and Effects in Treatment
Research has found melatonin’s effectiveness in treating various health afflictions, such as anxiety, behavioral and mood disorders, autoimmune disorders, infections and cancer. An increase of melatonin levels alleviates symptoms of depression, anxiety and stress because it is an anti-stress hormone and contains T-derived cytokines, which are mediators of melatonin’s immunological effects. Melatonin stimulates the immune system, and therefore, protects against damage from free radicals, and has positive effects on autoimmune disorders, general infections and cancer. Due to its ability to act as a powerful antioxidant, leading cancer researchers believe it may have the capability to protect DNA from damage and cell mutations that lead to cancer. Melatonin supplements have been used in combination with conventional anticancer therapies in clinical studies, with promising results. It has also been shown to increase the body’s levels of cancer-fighting proteins, referred to as cytokines, which improve symptoms and reduce cancer mortality rates. Although low melatonin levels are associated with individuals suffering from breast and prostate cancer, melatonin use as a treatment for these types of cancers is somewhat inconclusive and further research is needed to determine its effectiveness.
Other uses of melatonin include therapy supplementation for remission of neurological function in Multiple Sclerosis, the inhibition of platelet aggregation in cardiovascular disease and individuals suffering from migraines and cluster headaches. A double-blind, placebo-controlled study of 20 people revealed that 10 mg of melatonin administered daily reduced the frequency and severity of cluster headaches. In vitro fertilization (IVF) treatments at the Yamaguchi University Graduate School of Medicine have shown melatonin drastically increases IVF success rates, as well as pregnancy rates following transplantation. Because melatonin promotes the formation of bone and boosts the body’s immune response, it’s effective in supporting the body’s fight against periodontal bacteria and bone loss in the jaw, which results from periodontal disease. And lastly, melatonin improves blood cholesterol levels helps control weight gain.