Melatonin as an antioxidant

Melatonin has anti-inflammatory, free radical scavenger, and antioxidant effects. Studies have shown that it scavenges reactive nitrogen and oxygen species and boosts antioxidant defenses, thus preventing tissue damage. It also blocks pro-inflammatory cytokines.

Studies have shown that melatonin and its metabolites have antioxidant properties owing to their direct and indirect antioxidant actions. Melatonin crosses the cell membranes readily. It also crosses the blood-brain barrier with ease and protects your cells and tissues against damage caused by free radicals. In addition, it acts as a direct scavenger of reactive nitrogen and oxygen species. Also, melatonin can induce oxidative stress by boosting antioxidative defense systems, stimulating the function and expression of several antioxidant enzymes.

The high antioxidant profile of melatonin can help prevent cell damage and maintain the health of your eyes.

Studies have shown that melatonin could help treat conditions like age-related macular degeneration (AMD) and glaucoma (7).

In a study involving 100 AMD patients, it was found that supplementing with 3mg of melatonin for 6–24 months helped to protect the retina, delay damage due to aging, and preserve visual clarity (4).

Also, a rodent study found that melatonin decreased the incidence and severity of retinopathy — a disorder of the retina and can cause vision loss (8).

Dosage

You can take between 0.5–10mg of melatonin per day.

But it is important to note that melatonin supplements differ. Not all are the same. So you’re better off sticking to the recommended dosage on the label to avoid any adverse effects.

To find what works for you, you may want to begin with a lower dose and increase as required.

If you take melatonin supplements to improve your sleep, take them at least 30 minutes before bedtime to maximize their effectiveness.

On the other hand, if you are using melatonin to correct your circadian rhythm and create a regular sleep schedule, take it at least 2–3 hours before bedtime.

Does melatonin have any side effects?

Studies have shown that melatonin is safe for short-term and long-term use in adults. It is also non-addictive (9).

Although there are concerns in some quarters that supplementing with melatonin may decrease the natural melatonin production by your body, several studies show that this is untrue (10, 11).

Melatonin is not currently recommended for adolescents or children because long-term studies on its effects are limited to adults (12).

Commonly reported side effects of melatonin to include sleepiness, dizziness, headaches, and nausea (13).

Melatonin can also interact with some medications, such as blood pressure medications, blood thinners, and antidepressants (14), (15), (16).

Consult your healthcare provider before taking melatonin to prevent any side effects if you take these medications.