Melatonin is well-known as the sleep hormone, but experts say it can also boost immunity. The following details how melatonin can benefit your immune system.
- Modulates the immune system
- Enhances the innate and cellular immune systems
- Strengthens the adaptive immune system
- Early immune response
- Increased immune cell production & anti-aging properties
- Antioxidant & free radical scavenger
- May help prevent COVID
How melatonin can bolster your immune system
Melatonin may improve your immunity via multiple physiological mechanisms.
Melatonin modulates the immune system
Enhances the innate and cellular immune systems
Melatonin helps your body's natural defense system identify and attack invading pathogens and toxins. One study found that melatonin enhances both the innate and cellular immune systems (National Library of Medicine).
The innate immune system is the first part of the body to detect invaders such as viruses, bacteria and toxins and to sense wounds and other trauma. When it identifies an issue, the innate immune system activates cells to attack pathogens or repair wounds.
The cellular immune system plays a similar role on the intracellular level, destroying invaders that make their way inside your body's cells. In fact, some immune system cells – macrophages, mast cells and natural killer (NK) cells – can produce melatonin to act as an anti-inflammatory and antioxidant at the site of an injury (Sanesco).
"Melatonin is not only suitable for correcting sleep disorders but is also helpful for boosting one's immunity. This hormone enhances both innate and cellular immunity. It helps prevent you from seasonal viruses such as the flu," says Dr. Edna Skopljak, medical director and editor at Instador.
Strengthens the adaptive immune system
Melatonin can also strengthen the adaptive immune system, which recognizes and remembers specific threats. The adaptive immune system produces antibodies that help ward off future infections. For example, if you had measles as a child, your adaptive immune system is the reason you won't get it again.
Research has shown that Helper-T cell production increases after taking melatonin supplements. Helper T-cells are integral to adaptive immunity because they activate other infection-fighting cells, such as cytotoxic T-cells that kill pathogens and B-cells that produce antibodies (National Library of Medicine).
Early immune response
Melatonin can also help stimulate the immune system into a pre-activated state, triggering an early immune response for those in immunosuppressed conditions. As one National Institute of Health study puts it, "the role of melatonin as an effector that can modulate the immune system is undeniable."
Melatonin is an immunostimulant
Melatonin stimulates the production of molecules that trigger immunological response, including IL-2, IL-6 and IL-12 (Sanesco).
"Melatonin has been proven to be beneficial for the immune system," says Dr. Kellie Middleton, MD/MPH, an orthopaedic surgeon in Atlanta. "Studies have shown that melatonin can stimulate the production of numerous substances, such as cytokines, which help support the immune system. Melatonin helps reduce inflammation, reducing the risk of various illnesses."
Melatonin increases immune cell production and has anti-aging properties
Our immune system becomes less effective over time due to a decrease in the functional activity of specific cells, including:
- NK cells: White blood cells that kill other infected cells and tumor cells
- Granulocytes: White blood cells that release enzymes when the body is under attack
- Macrophages: White blood cells that surround and kill pathogens and stimulate other immune cells
Melatonin stimulates the production of progenitor cells, which are similar to stem cells in that they can turn into specialized cells such as NK cells, granulocytes and macrophages. In this manner, melatonin can enhance
immunity and delay age-associated decline in immune function (National Library of Medicine).
“There are different reasons why immunity might suffer or decrease. However, the main cause of this decrease is the natural process of aging. Melatonin is already present in the body but declines after a certain age. Taking melatonin as a dietary supplement will greatly affect immunity as it has anti-aging properties,” says Melissa Collins, food scientist and director of content at Jupiter. “Melatonin has an immunomodulatory role in humans. The profound, time-dependent influence of melatonin on certain cells is fundamentally important to the immune system.”
Melatonin is an antioxidant and free radical scavenger
Free radicals are unstable molecules that can damage cells and DNA, and oxidative stress occurs when there is an imbalance between free radicals (also known as reactive oxygen species) and antioxidant defenses in the body.
Melatonin acts as an antioxidant – a free radical scavenger that can bind and neutralize as many as ten different types of free radicals (National Library of Medicine). In other words, melatonin prevents oxidative stress linked to various health issues, including neurological disease, cardiovascular disease, kidney disease, arthritis and cancer (National Library of Medicine).
“Melatonin has been shown to have antioxidant effects, which may help protect cells from damage caused by free radicals,” says Lisa Richards, a nutritionist and author of The Candida Diet. “Melatonin may also help to regulate immune system function by modulating the activity of certain immune cells.”
Melatonin is an anti-inflammatory
Melatonin is unique in that it can act as a pro-inflammatory during some immune responses and as an anti-inflammatory during others (Journal of Pineal Research). For this reason, it’s been referred to as an immunological buffer.
As a pro-inflammatory, melatonin can support cells that attack, kill and eliminate pathogens. In the case of acute inflammation, however, melatonin can behave as an anti-inflammatory molecule to reduce tissue destruction and macromolecular damage in organs (National Library of Medicine).
Melatonin may help prevent COVID
Research has shown that melatonin’s antioxidant and anti-inflammatory properties may help prevent and fight COVID-19 infections. In one study, people who took melatonin were 28% less likely to get COVID – and that number increased to 52% for African Americans (PLOS Journal).
Other researchers have found that taking melatonin two weeks before and up to four weeks after getting the COVID-19 vaccine can make the vaccine more effective and last longer while preventing adverse effects.
Melatonin is often indicated for sleep, but its immune-boosting properties shouldn’t be overlooked. Evidence suggests that melatonin supplements could positively affect health by modulating immune function, neutralizing free radicals and reducing inflammation. Speak to your doctor to determine whether melatonin is a good option as part of your overall immune-boosting strategy.
“It’s important to remember that a healthy immune system is supported by a variety of factors, including a healthy diet, sufficient sleep, regular physical activity and stress management,” says Richards. “It’s always a good idea to adopt a healthy lifestyle and seek medical care when needed to support overall health and immunity.”
Disclaimer: The information stated in this article is for educational purposes only. The information stated is not intended to treat, diagnose or cure any disease, condition, or other physical or mental ailment of the human body. The desire to make any changes to one's dietary habits or supplementation should be consulted and discussed with a licensed medical professional.