How Melatonin Helps You Sleep
How to use the hormone effectively.
Posted September 15, 2017
When I travel—which I seem to be doing a lot of these days—I use melatonin to help with jetlag (0.5mg, ninety minutes before I want to go to sleep in my new destination, with 20 minutes of light therapy in the morning).
Jetlag can be complicated—there are many factors that influence how severely you experience jetlag, including:
- What is your chronotype?
- What time zone are you in?
- Where are you going?
- What is the direction of travel?
- What time is your flight?
There are a number of hormones in the body that influence sleep, but only one carries the nickname “the sleep hormone.” That’s melatonin. Melatonin is central to sleep, to our daily cycles of rest and activity, and to the regulation of the body’s biorhythms. Melatonin plays an essential role in keeping our bodies functioning on our best bio time. This, in turn, has broad effects on our overall health.
What is melatonin?
Melatonin is a hormone the body produces naturally. Natural melatonin is produced primarily by the pineal gland in the brain. Melatonin has a daily biorhythm—levels rise and fall throughout the day and night, reaching their highest levels in the evening and falling to their lowest levels in the morning. This daily melatonin biorhythm is strongly tied to the 24-hour cycle of light and dark. This is a key reason why nighttime light exposure can be so detrimental to sleep and to health.
Dietary sources of melatonin
Can dietary choices influence melatonin levels? In recent years, there’s been increasing scientific attention to the relationship of melatonin and diet. Cherries are known to be naturally high in melatonin. A recent study looked at whether drinking tart cherry juice would improve melatonin levels and sleep. Among the tart cherry-juice drinkers, melatonin levels and serotonin levels rose significantly. This group also experienced significant improvements to their sleep—they slept more and improved their sleep efficiency. The study used Montmorency tart cherry juice.
Some foods that are part of the Mediterranean diet are high in melatonin, including grapeseeds, tomatoes and bell peppers, and walnuts. The amino acid tryptophan is required for the body to make melatonin. Recent research indicates that eating tryptophan-rich foods may be beneficial for melatonin levels and for sleep.
Supplemental melatonin is produced synthetically and is most often used in pill form. Here’s some important information to know, when considering using a melatonin supplement: A recent scientific investigation found that the actual melatonin content found in many supplements on the market may vary significantly from what product labels claim. Scientists at Ontario’s University of Guelph found that in more than 71 percent of melatonin supplements, the amount of melatonin was more than 10 percent different from what the product label indicated. Some products contained as much as 83 percent less melatonin, while other products contained as much as 478 percent more melatonin. That means a great many consumers aren’t taking what they think they are when they use a melatonin supplement. Before you begin using melatonin, be sure to do your research and get your melatonin from a trusted source.
Scientific research on the effects of melatonin on sleep and health have been underway since the discovery of the hormone in 1958. In 1994, the first melatonin supplements became available.
How does melatonin work?
Melatonin production in the body is triggered by darkness and suppressed by light. The brain receives light and dark cues through the retina of the eye, which are then communicated along the optic nerve to the brain’s master bio clock, the suprachiasmatic nucleus, or SCN. This bio clock controls the flow of melatonin and other hormones—as well as a vast array of other physiological processes.
When it’s dark, the SCN gives the go-ahead to the pineal gland to ramp up its production of melatonin. Typically, melatonin levels begin to rise significantly around 9 p.m., and peak during the overnight hours before falling to very low levels shortly before dawn. Melatonin stays low throughout the daylight hours, as other hormones rise to help maintain focus, energy, and alertness throughout the day.
The length of melatonin production shifts throughout the year, with shorter daily periods of melatonin production in the summer when days are longer, and longer periods in the winter, when nights are longer. Melatonin production decreases with age, which may contribute to increased sleep problems, as well as to overall aging and vulnerability to disease.
Disruptions in natural melatonin levels can go hand-in-hand with sleep problems.
Benefits of melatonin: Melatonin, healthy sleep, and bio time
Melatonin is not a sedative. Instead, it works to promote sleep by helping to regulate the body’s bio clock and sleep-wake cycles. Scientific research shows that melatonin may help to strengthen and improve sleep-wake cycles, making it possible to adhere to more healthful sleep patterns and making it easier to sleep on a regular schedule. Research indicates that melatonin may shorten the time it takes to fall asleep, and increase overall sleep amounts. Melatonin also may improve the quality of sleep and reduce daytime sleepiness and fatigue. Studies also show melatonin may increase REM sleep.
When you sleep better and your bio clock is running in sync, it can help improve your mood, daytime performance, energy levels and your overall health, including immune function, and regulation of metabolism, digestion, and appetite.
In addition to strengthening the body’s bio clock and sleep-wake cycles, specific sleep problems that scientific research shows may benefit from supplemental melatonin include:
- Sleep problems associated with shift work
- Sleep problems associated with other medical conditions, such as high blood pressure, and ADHD
- Sleep problems associated with menopause
- Restless leg syndrome
- Jet lag
- Sleep problems in children with autism and other developmental disorders
- Reduced REM sleep
- Circadian rhythm disorders in the blind
Melatonin, brain health, and beyond
In recent years, we’ve learned a lot about the power of melatonin as an antioxidant and about its impact on healthy brain function. Increasingly, melatonin is considered able to play an important role in protecting against cognitive impairment and neurodegenerative disease that come about from age and also from injury.
As an antioxidant, melatonin may work to protect against cell damage. Oxidative damage to brain cells is believed to be a prime factor in age-related cognitive problems and to neurodegenerative diseases such as Alzheimer’s disease and others. Melatonin functions as a powerful antioxidant in the brain—but its antioxidant capabilities are not limited to the brain. As an antioxidant, melatonin appears to have protective effects on the cardiovascular system and other physiological systems as well. Recent research shows that melatonin may exert its protective, antioxidant effect on neural cells, helping to delay or prevent cognitive impairment and memory loss.
Melatonin also may be effective in helping to lower high blood pressure, according to research.
Melatonin and cancer therapy
One exciting area of study for melatonin involves its potential in treating some forms of cancer. Melatonin has been shown to slow the growth of some types of cancerous tumors and is being investigated as a possible therapy for several different types of cancer. According to research, melatonin may also be effective in treating the side effects of other cancer treatments, including chemotherapy.
Melatonin and autism spectrum disorders
Many children and adults with autism spectrum disorder, or ASD, have trouble sleeping. Scientific research has found that people with autism spectrum disorders may have abnormalities to their natural melatonin levels. Research suggests people with ASD may have lower concentrations of nighttime melatonin. Some studies have also found correlations between abnormal melatonin levels and the severity of ASD symptoms. Supplemental melatonin may be effective at improving sleep quality and sleep quantity in people with ASD, and also may help improve daytime behavior.
Other possible uses for melatonin
Our understanding of melatonin is expanding rapidly, as scientists continue to study how the hormone works in the body, how it contributes to health and disease protection, and how melatonin may be used as a therapeutic treatment. The effectiveness of melatonin is being investigated for several other medical conditions, including:
- Age-related macular degeneration
- Chronic Fatigue Syndrome (CFS)
- Irritable bowel syndrome
- Menopause symptoms
- Metabolic syndrome
- Migraine and other types of headache
Melatonin: what to know
Always consult your doctor before you begin taking a supplement or make any changes to your existing medication and supplement routine. This is not medical advice, but it is information you can use as a conversation-starter with your physician at your next appointment.
The following doses are based on amounts that have been investigated in scientific studies. In general, for sleep problems, it is recommended that users begin with the smallest suggested dose, and gradually increase until it has an effect.
- For regulation of sleep-wake cycles: 0.3mg to 5mg
- For insomnia: 2-3mg; in some research, higher doses have been used for short-term use
- For jet lag: 0.5mg to8 mg, starting upon day of arrival at destination
- For sleep-wake cycle disruptions: 2mg to 12mg
- For delayed sleep phase syndrome: 3-5mg
- For sleep and sleep-wake cycle disruptions in the blind: 0.5mg to 5 mg
The half-life of melatonin is between 20 to 50 minutes. Half-life refers to the amount of time it takes for a supplement or medication to reduce its concentration by 50 percent once in the body.
Possible side effects of melatonin
Generally, melatonin is well tolerated by healthy adults. There are possible side effects of melatonin, including headaches, daytime sleepiness, dizziness, stomach irritation or cramping, irritability, and short-term depression. Because of the potential for dizziness and sleepiness, it is recommended that people not drive within five hours of taking melatonin.
People with the following conditions should consult with a physician before beginning to use a melatonin supplement:
- Pregnancy, and women who are breastfeeding (It is recommended that women who are pregnant or breastfeeding not use melatonin.)
- Bleeding disorders
- High blood pressure
- Seizure disorders
- Transplant recipients
The following medications and other supplements may interact with melatonin. Effects may include increasing or decreasing the amount of melatonin in the body, interfering with the effectiveness of the medications or supplements, and interfering with the condition that is being treated by the medication or supplement. This is a list of commonly used medications and supplements that have scientifically identified interactions with melatonin. People who take these or any other medications and supplements should consult with a physician before beginning to use a melatonin supplement.
Interactions with medications
- Anticonvulsant and other seizure-related medications
- Antidepressant medications
- Antipsychotic medications
- Anticoagulant medications
- Contraceptive medications
- Diabetes medications
- High blood pressure medications
- Immunosuppressant medications
- Non-steroidal anti-inflammatory (NSAID) medications
- Sedative medications
- Medications that are altered or broken down by the liver
Interactions with other supplements
- Supplements that target high blood pressure (Andrographis, casein peptides, cat’s claw, coenzyme Q-10, fish oil, L-arginine, lyceum, stinging nettle, theanine, and others)
- Supplements that may lower seizure threshold (butanediol, cedar leaf, Chinese club moss, EDTA, folic acid, GBL, GHB, glutamine, huperzine A, hydrazine sulfate, hyssop oil, juniper, L-carnitine, rosemary, sage, wormwood, and others)
- Supplements that may reduce blood clotting (angelica, clove, danshen, garlic, ginger, ginkgo, Panax ginseng, red clover, will, and others)
- Supplements that may function as sedatives (5-HTP, calamus, California poppy, catnip, hops, Jamaican dogwood, kava, St. John’s wort, skullcap, valerian, yerba mansa, and others)
- Vitamin B 12
How melatonin can work with your chronotype
All four chronotypes may benefit from using melatonin to help strengthen and regulate sleep-wake cycles and improve sleep. The best time to take melatonin will differ from chronotype to chronotype. Lions will tend to take melatonin earlier in the evenings than other chronotypes, while wolves and dolphins will need to take melatonin later than Lions and Bears. The best time to take a melatonin supplement is about 30 minutes to one hour before bedtime.
Melatonin is one of the most important hormones in the body, essential to sleep and to overall health. This “sleep hormone” has a role in a great deal more than sleep—and may prove to be an increasingly versatile therapy to fight aging and disease.
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