Melatonin is a hormone produced by the pineal gland in the brain that regulates sleep and wake cycles. It is also known as the "sleep hormone" because it helps to promote sleepiness and regulate the body's internal clock.

Melatonin is released in response to darkness and suppressed by light exposure. This means that melatonin is typically produced at night and decreases during the day, helping to regulate the body's sleep-wake cycle.

Melatonin supplements are often used as a sleep aid for individuals who have trouble falling asleep or staying asleep. They are also used to help regulate sleep patterns in individuals who work night shifts or have jet lag.

In addition to its sleep-regulating effects, melatonin has been found to have antioxidant and anti-inflammatory properties. It has also been studied for its potential role in treating a variety of conditions, including depression, anxiety, and migraine headaches.

While melatonin supplements are generally considered safe for short-term use, they can cause side effects such as dizziness, headaches, and nausea. It is important to talk to a healthcare provider before starting any new supplement or medication.

References:

• National Sleep Foundation. (n.d.). Melatonin and Sleep. Retrieved from https://www.sleepfoundation.org/articles/melatonin-and-sleep
• Mayo Clinic. (2020). Melatonin. Retrieved from https://www.mayoclinic.org/drugs-supplements-melatonin/art-20363071
• University of Maryland Medical Center. (2019). Melatonin. Retrieved from https://www.umm.edu/health/medical/altmed/supplement/melatonin