What is melatonin?

Melatonin, or N-acetyl-5-methoxytryptamine, is a hormone primarily synthesized in the pineal gland from tryptophan (one of the essential amino acids in the human body). Smaller amounts of this hormone can also be produced in the gastrointestinal tract, thymus, retina, bone marrow, and lymphocytes [1-3].

Melatonin produced naturally in the body is known as endogenous melatonin (also referred to as the "sleep hormone"). However, it can also be supplied to the body from external sources, such as dietary supplements. In this case, we refer to it as exogenous melatonin [1].

How is melatonin produced and how does it work?

Melatonin is best known for its role in regulating the circadian rhythm, specifically promoting sleep and inhibiting wake signals. The circadian rhythm is simply the natural cycle that governs the intensification and reduction of our life processes throughout the day. Although melatonin is secreted to some extent throughout the day, its synthesis increases in the evening, peaking between 2 AM and 4 AM. It is important to know that melatonin secretion is influenced by darkness, while light (including that emitted from our TVs, computers, and phones) inhibits it [1-2].

Once in the bloodstream, this hormone reaches melatonin receptors (particularly MT1 and MT2), where it helps maintain appropriate sleep patterns [3].

How does melatonin support the body?

Thanks to melatonin, the body knows when it should go to sleep, and you feel sleepy. This hormone regulates the circadian rhythm, an important aspect of which is ensuring the appropriate length and quality of sleep. Proper nighttime rest is fundamental to the functioning of the entire body. However, this is not the only action of melatonin. In addition, it may exhibit properties that are:

• antioxidant,
• anti-inflammatory,
• regulating immune system function,
• supporting the cardiovascular system,
• beneficial for bone formation and protection.

Some studies also suggest that it may help prevent migraines and reduce the risk of neurodegenerative diseases [1, 3-5].

What foods contain melatonin?

The highest concentrations of melatonin are found in white sesame seeds, soybeans, sunflower seeds, and nuts. You can also find a high content of this component in eggs and fish [6-7]. The natural synthesis of melatonin is also supported by foods rich in tryptophan, as this is the amino acid necessary for the production of this hormone.

You can find tryptophan primarily in:

• milk,
• cheese,
• meat (including fish),
• eggs,
• bananas,
• pumpkin and sesame seeds,
• dates,
• nuts,
• chocolate [8].

Can everyone take melatonin?

Research indicates that melatonin levels in the body decrease with age [2]. This is why many adults suffer from sleep problems and do not get the recommended amount of sleep each day. Melatonin has proven effectiveness in supporting proper sleep and can be helpful for those struggling with insomnia or other circadian rhythm disorders (e.g., jet lag) [1-2, 9-10]. For this reason, many dietary supplements containing this ingredient are available on the market.

However, can everyone take it?

Melatonin is a safe ingredient, but it can interact with medications. People taking medications should consult a doctor before starting supplementation. Additionally, melatonin is not recommended for:

• pregnant and breastfeeding women,
• people suffering from autoimmune diseases (e.g., rheumatoid arthritis),
• people with kidney and liver disorders [1, 11].

The best dietary supplements for sleep

Do you want to fall asleep quickly, not wake up during the night, and feel refreshed in the morning? Try the safe dietary supplements from Osavi, composed of the highest quality active ingredients that will improve your sleep.

Take advantage of the power of the “sleep hormone,” supported by plant extracts:

• Melatonin 1 mg with valerian and lemon balm – in capsule form,
• Melatonin 1 mg with passionflower – in the form of an oral spray.

And if you are a fan of the health benefits of plants, reach for Herbal Sleep Support. These are capsules that contain standardized extracts of hops, passionflower, and lemon balm, which will help you calm down and relax.

Sources:

1. Savage, Rosemary A., et al. “Melatonin.” StatPearls, StatPearls Publishing, 2025. PubMed, http://www.ncbi.nlm.nih.gov/books/NBK534823/.
2. Kamfar, Waad W., et al. “Comprehensive review of melatonin as a promising nutritional and nutraceutical supplement.” Heliyon, vol. 10, no. 2, January 2024, p. e24266. ScienceDirect, https://doi.org/10.1016/j.heliyon.2024.e24266.
3. Ahmad, Sheikh Bilal, et al. “Melatonin and Health: Insights of Melatonin Action, Biological Functions, and Associated Disorders.” Cellular and Molecular Neurobiology, vol. 43, no. 6, August 2023, pp. 2437–58. Springer Link, https://doi.org/10.1007/s10571-023-01324-w.
4. Tordjman, Sylvie, et al. “Melatonin: Pharmacology, Functions and Therapeutic Benefits.” Current Neuropharmacology, vol. 15, no. 3, April 2017, pp. 434–43. PubMed Central, https://doi.org/10.2174/1570159X14666161228122115.
5. Tarocco, Anna, et al. “Melatonin as a Master Regulator of Cell Death and Inflammation: Molecular Mechanisms and Clinical Implications for Newborn Care.” Cell Death & Disease, vol. 10, no. 4, April 2019, pp. 1–12. www.nature.com, https://doi.org/10.1038/s41419-019-1556-7.
6. Sangsopha, Jintana, et al. “Dietary sources of melatonin and benefits from production of high melatonin pasteurized milk.” Journal of Food Science and Technology, vol. 57, no. 6, June 2020, pp. 2026–37. PubMed Central, https://doi.org/10.1007/s13197-020-04236-5.
7. Meng, Xiao, et al. “Dietary Sources and Bioactivities of Melatonin.” Nutrients, vol. 9, no. 4, April 2017, p. 367. PubMed Central, https://doi.org/10.3390/nu9040367.
8. Nayak, Bichitra N., et al. “Chapter 51 - Biochemical and dietary functions of tryptophan and its metabolites in human health.” Functional Foods and Nutraceuticals in Metabolic and Non-Communicable Diseases, edited by Ram B. Singh et al., Academic Press, 2022, pp. 783–98. ScienceDirect, https://doi.org/10.1016/B978-0-12-819815-5.00003-3.
9. Poza, J. J., et al. “Melatonin in sleep disorders.” Neurología (English Edition), vol. 37, no. 7, September 2022, pp. 575–85. ScienceDirect, https://doi.org/10.1016/j.nrleng.2018.08.004.
10. Costello, Rebecca B., et al. “The effectiveness of melatonin for promoting healthy sleep: a rapid evidence