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Melatonin has a central role in regulating the immune system.

Research shows melatonin is a potent antioxidant and could help prevent tissue damage and cancer.

Chronic sleep deprivation impairs immune response and contributes to inflammation.

Melatonin is widely known as the substance that makes us sleepy. It is commonly used as an over-the-counter sleep aid to treat jet lag and bouts of insomnia. However, new research shows that melatonin plays a wider role in maintaining overall health. Melatonin is a potent antioxidant that can prevent tissue damage. Evidence suggests it could help ward off certain types of cancer (Proietti, Reiter & Bizzarriet, 2012). It plays an essential role in the immune system’s ability to fight infections and heal from injuries (Szataniak & Packi, 2025; Singh et al., 2024).

Melatonin (N-acetyl-5-methoxytryptamine) is known as a chronobiotic hormone, which means that it regulates circadian rhythm. Tryptophan, an amino acid ingested from certain foods, serves as a building block for the production of serotonin. Serotonin, a neurotransmitter involved in mood regulation, is converted to melatonin primarily in the brain’s pineal gland. Production of melatonin is increased during darkness at night and it is released directly into the bloodstream. Levels decline during the day as production is inhibited by light (Kamfar et al., 2024).

Immune system functions in tandem with sleep

Sleep has long been known to promote healing. People need extra sleep to recover from physical ailments. Research published in 2025 by Szataniak et al. showed that immune responses are strongly affected by the sleep cycle. The authors analysed 59 studies published from 2000-2025 that examined how melatonin production affects the immune system. They found that chronic sleep deprivation impairs immune response which increases susceptibility to infections and inflammation (Szataniak, et al 2025).

Immune system activity during........

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