Melatonin – meaning, action, deficiency, excess

Melatonin, commonly known as the sleep hormone, is another hormone discussed by experts collaborating with ONSEN® in response to readers' requests on the best sleep blog.

As with almost every hormone, even the slightest disturbance in melatonin levels can result in dysregulation of the entire hormonal system. Our biopsychosocial functioning throughout the day and the ability to have comfortable and restorative sleep at night depend on this system.

That's why it's important to know not only what melatonin is but also how it works. This knowledge can help predict the consequences of melatonin deficiency or excess and identify potential symptoms of disorders early on.

Melatonin, known as the sleep hormone and the hormone of darkness, is actually a hormone that regulates the circadian rhythm. Produced in the pineal gland, melatonin is primarily responsible for maintaining the sleep-wake cycle. Its action is based on coordinating with the human biological clock and lowering body temperature. Additionally, melatonin plays a role in counteracting aging due to its anti-gonadotropic activity.

Moreover, melatonin has shown positive effects in certain types of cancer. Administering melatonin to individuals with pancreatic cancer induces apoptosis, which is the spontaneous destruction of cancer cells. Therefore, its level in the blood is extremely important for individuals at risk of developing cancer.

Melatonin also enhances the immune system as it acts as a potent antioxidant. It also influences digestive processes by stimulating increased secretion of enzymes from the pancreas.

The normal level of melatonin in the blood serum depends on age and the laboratory performing the test. Generally, the normal level of melatonin decreases with age.

• In children up to 3 years old, the normal level of melatonin is approximately 250 pg/ml.
• In children from 4 to 15 years old, the normal level of melatonin ranges from 120 pg/ml to 240 pg/ml.
• In adolescents and adults, the normal level of melatonin ranges from 70 pg/ml to 80 pg/ml.
• In middle-aged individuals, the normal level of melatonin ranges from 30 pg/ml to 70 pg/ml.
• In individuals above 65 years old, the normal level of melatonin ranges from 20 pg/ml to 30 pg/ml.

Melatonin is secreted by the pineal gland. Its secretion also occurs in the retina of the eye and enterochromaffin cells of the digestive tract. Its secretion is dependent on the influx of light and tends to increase in darkness and decrease with exposure to light. The properties of melatonin make it a valuable sleep hormone as it facilitates falling asleep and promotes proper body regeneration.

The action of melatonin, which is derived from tryptophan, is closely related to the level of serotonin, which is one of the products of its synthesis. Therefore, melatonin can also be associated with mood. As a result, melatonin is considered one of the key hormones that influence the biopsychosocial functioning of humans.

Additionally, melatonin has become a popular dietary supplement. Sold in the form of tablets or capsules, melatonin is intended to facilitate sleep in circadian rhythm disorders. However, it should only be supplemented by blind individuals and those over the age of 65. Nevertheless, it is often used by younger individuals, which increases the risk of melatonin overdose, which can sometimes even lead to death.

However, melatonin does not have a strong sleep-inducing effect and does not exhibit many other side effects. Its action is also not addictive. Despite this, great caution should be exercised because melatonin is still a hormone, and any disruption of its natural levels in the blood can affect the balance of the entire hormonal system.

The deficiency of melatonin can be associated with disorders of the pineal gland, where it is produced, as well as other glands. The most commonly observed causes of melatonin deficiency include:

• Low level of physical activity;
• Excessive exposure to light;
• Poor diet;
• Unhealthy lifestyle;
• Prolonged past supplementation of melatonin;
• Tumors - especially in the pineal gland.

Maintaining a low level of melatonin in the blood is not recommended. The most frequently reported effects of melatonin deficiency, alongside insomnia, include:

• Headaches;
• Weakened cognitive function;
• Daytime sleepiness;
• Chronic fatigue;
• Mood disorders;
• Sleep onset disorders;
• Disturbances in sleep-wake rhythm.

An excess of melatonin is most commonly associated with disorders of the hormonal system. The most frequently observed causes of melatonin excess are:

Sustained high levels of excess in the blood are not desirable. The most commonly reported effects of melatonin excess are:

Health and Rehabilitation Psychologist collaborating  with ONSEN®, Mateusz Nesterok, draws attention to the consequences of melatonin excess. While melatonin is essential for life and plays a positive role, it is crucial to maintain its optimal level for good health. Excessive melatonin, particularly melatonin overdose, can cause hypothermia, which in extreme cases can lead to death. Improper melatonin supplementation can intensify sleep disorders and disrupt the hormonal system

He points out that a too low level of melatonin is also undesirable for humans. Melatonin levels below the norm can lead to headaches and daytime sleepiness. Furthermore, any deviation from the physiological level of melatonin in the blood can cause disturbances in the sleep-wake cycle and, consequently, even lead to depression.

As scientific studies show, melatonin supplementation brings significant benefits for blind individuals. This is because they do not naturally produce sufficient melatonin due to the insensitivity of their eyes to light. Similar effects are observed in older individuals, particularly those over 65 years old. However, other individuals should not take melatonin dietary supplements without clear medical recommendations, especially children.

Maintaining an optimal level of melatonin in the blood is facilitated by comfortable, healthy sleep. Achieving this requires a functional mattress that provides ideal body support and spinal support. Preserving the physiological curves of the spine during sleep and allowing the body to fully relax has a beneficial effect on all its systems, including the hormonal system.

ONSEN® offers the Osaka Air mattress, which is the most functional mattress available on the market. Its jobs to be done are to meet the users' needs and to effectively solve problems they may have. Thanks to this, it has become a cult product that fulfills all 10 basic mattress functionalities and allows for comfortable and healthy sleep. Moreover, like all ONSEN® products, the mattress is covered by even a 15-year warranty, as well as a program allowing for return within 100 days, minimizing the purchase risk to zero.

We also encourage you to explore other articles on the best sleep and health blog, as well as the Encyclopedia of Healthy Sleep prepared by the ONSEN® team of specialists. For those who care about spine health, we recommend a set of spine exercises prepared by our physiotherapist.