Melatonin is a natural hormone produced by the pineal gland - a small, pea-shaped gland in the center of the brain. It is crucial to our sleep-wake cycle and is sometimes referred to as the "sleep hormone". The production of the molecule is dependent on the brightness of our environment. In the dark, more is produced, which makes us sleepy, while production decreases in bright light, which keeps us awake and "alert". It is in many ways the antagonist of cortisol.
The primary function is the regulation of sleep. The vital substance signals to our body when it is time to sleep and wake up. This is closely linked to our circadian rhythm , the internal clock that determines our daily cycle of sleep and wakefulness. Melatonin plays an essential role in setting this rhythm based on the light we are exposed to.
What influences our melatonin production
Lifestyle changes can affect the body's production. For example, a change in sleep habits, diet or exposure to light can affect melatonin levels in the body. The blue light often emitted by electronic devices such as smartphones and computers can inhibit melatonin production making it difficult to fall asleep. It is therefore recommended to reduce exposure to blue light in the evening hours to ensure a good quality of sleep.
Where is melatonin found?
In addition to dietary supplements, the molecule can also be found in certain foods. These include fruit and vegetables such as cherries, corn, asparagus, tomatoes, pomegranates, olives, grapes, broccoli and cucumbers. Some cereals, nuts and seeds such as rice, barley, oats, walnuts and linseed also contain higher amounts. It is also found in some proteins, including poultry, fish and dairy products. The concentration of melatonin is particularly high in tart cherries Montmorency, which you will find in some sleep supplements .
As already mentioned, our brain also produces melatonin. This starts with the amino acid tryptophan. It is converted into another compound called 5-hydroxytryptophan with the help of enzymes. This is then converted into serotonin, a neurotransmitter associated with feelings of well-being and happiness. When it gets dark, the serotonin in the pineal gland is converted into melatonin. The pineal gland then releases the sleep hormone into the bloodstream.
Did you know
Our intestinal bacteria are crucially involved in the production of serotonin . A whole 90% of the hormone is found in the intestine! The starting point here is also the amino acid tryptophan, which can be converted by our microbiome via three different metabolic pathways. If our microbiome is out of balance (dysbiosis), production can be impaired. Probiotics and prebiotics can help in this case.
Health effects of melatonin
Sleep quality and duration
In a double-blind study the efficacy of melatonin in improving sleep in cancer patients with insomnia was investigated. 50 patients received either 3 mg melatonin or a placebo orally daily for 14 days. The results showed significant differences in favor of melatonin treatment in terms of clinically relevant improvements in insomnia.
In a large meta-analysis, the effects of melatonin on primary sleep disorders were investigated using 19 studies with 1683 participants. Compared to placebo it significantly reduced the time to fall asleep and increased total sleep time. Long-term studies and studies with higher doses showed greater effects on reducing sleep onset latency and increasing total sleep time. Overall sleep quality improved significantly in subjects taking melatonin compared to placebo. The results suggest that the molecule reduces sleep onset latency, increases total sleep time and improves overall sleep qualityin the long term.
Gastroesophageal reflux disease
In this study, the role of exogenous melatonin in the treatment of gastroesophageal reflux disease (GERD) was investigated in 36 people. Participants were divided into four groups and treated with melatonin alone, an acid blocker alone or a combination of both for 4 and 8 weeks. The results showed that the "sleep hormone", alone or in combination with the PPI, contributed to the improvement of reflux disease, with the acid blocker alone being more effective compared to melatonin monotherapy. The researchers concluded: Melatonin is a promising therapeutic agent for the treatment of GERD, however, further studies are needed to confirm the efficacy and long-term safety of melatonin.
Human growth hormone
In a double-blind, randomized crossover study the influence of exogenous melatonin in different doses (0.05 mg, 0.5 mg or 5.0 mg) on the release of pituitary hormones was investigated in eight healthy male volunteers. The results showed that melatonin caused dose-dependent changes in circulating concentrations of oxytocin and vasopressin, with a dose of 0.5 mg having a stimulatory effect and 5.0 mg having an inhibitory effect. These two doses stimulated the release of growth hormones.
Various forms of melatonin as a supplement
The sleep hormone is available in various forms, including tablets, capsules, drops and sprays. The choice of form often depends on personal preference and individual needs. Melatonin sprays are sometimes preferred as they allow for faster absorption, while tablets and capsules can offer a slower release of the hormone.
Side effects of melatonin
In general, the sleep hormone is considered safe. Nevertheless, side effects can occur when taking melatonin supplements, including headaches, dizziness, nausea and drowsiness. There are also concerns about possible interactions with other medications, particularly blood-thinning medications and antidepressants. It is important to talk to a doctor before taking melatonin, especially if you are taking other medications or have certain health conditions.
Is an overdose possible?
An overdose of melatonin can lead to various undesirable side effects, including drowsiness the next day, confusion, headaches, dizziness, stomach problems and even hallucinations. Especially in children, an overdose of melatonin can lead to unpredictable reactions, as their organism can react more sensitively to hormone changes. It is therefore important not to exceed the recommended dosage.
Can the sleep hormone be addictive?
As far as addictiveness is concerned, melatonin is generally not addictive because it is a hormone and not a substance that causes a euphoric or rewarding feeling. Nevertheless, abusing melatonin to treat sleep disorders can cause the body to become habituated to it and develop a dependence on it. It is important to take melatonin only as directed and not to abuse it as a long-term solution to sleep problems. For persistent sleep disorders, it is advisable to treat the underlying causes and consider alternative treatments.
Melatonin gummy bears: A sweet alternative?
Melatonin gummy bears are a relatively new form of melatonin supplements that are particularly popular with children and people with swallowing difficulties. These gummy bears contain a specific amount of the sleep hormone per serving and offer a convenient and easy-to-dose option for those who have difficulty taking conventional tablets.
How dangerous are the gummy bears?
Pediatricians have expressed increasing concerns about the use of melatonin gummy bears in children. These concerns relate to the potential overdose of the sleep hormone as well as the long-term effects on children's health and development. Since the dosage of melatonin in gummy bears often cannot be precisely controlled and children tend to consume more than the recommended amount, there is a risk of unwanted side effects such as drowsiness the next day, mood swings and possibly even hormonal imbalances. Pediatricians therefore recommend treating the use of melatonin gummy bears in children with caution and considering alternative approaches to treating sleep disorders, especially with long-term use. It is advisable to consult a pediatrician before using melatonin in children to ensure appropriate dosing and use.
Melatonin & amp; Longevity
Studies have shown that melatonin may play a role in extending longevity and health in old age. A study from 2017 has uncovered a link between melatonin and cellular health, which contributes to longevity. It was about the Hallmarks of Agin g, more specifically about the function of the mitochondria , the powerhouses of our cells. These become weaker and weaker with age, resulting in mitochondrial dysfunction . The NAD levels fall and this slows down the energy metabolism. You can find out more about this in our detailed NAD-article.
What happens in old age
Several factors can contribute to lower melatonin levels in old age. One of the main reasons is the natural aging process, which may be associated with changes in the functioning of the pineal gland, the main organ for melatonin production in the body. As we age, the number and function of pineal gland cells decreases, which can lead to reduced production of melatonin.
In addition, age-related changes in sleep patterns and light exposure can affect melatonin production. Older people tend to have less deep sleep and may be more prone to sleep disorders such as insomnia. This can lead to reduced melatonin production, as melatonin is normally released during sleep.
In addition, age-related diseases such as diabetes, heart disease and neurological disorders can also affect melatonin production. These diseases can directly affect the function of the pineal gland or influence other factors in the body that regulate melatonin production.
Another important aspect is exposure to light. Older people may spend less time outdoors and be exposed to less sunlight, which can affect the natural synthesis of melatonin, as sunlight is an important stimulus for the production of this hormone.
Therefore, it is thought that maintaining high levels of melatonin in the body may help to delay or minimize the negative effects of aging.
