Diseases, Conditions, Syndromes

Researchers identify melatonin as possible COVID-19 treatment

Results from a new Cleveland Clinic-led study suggest that melatonin, a hormone that regulates the sleep-wake cycle and is commonly used as an over-the-counter sleep aid, may be a viable treatment option for COVID-19.

Medical research

Melatonin: finally, a supplement that actually boosts memory

Walk down the supplement aisle in your local drugstore and you'll find fish oil, ginkgo, vitamin E, and ginseng, all touted as memory boosters that can help you avoid cognitive decline. You'll also find melatonin, which is ...

Health

'White' light suppresses the body's production of melatonin

Exposure to the light of white LED bulbs, it turns out, suppresses melatonin 5 times more than exposure to the light of High Pressure Sodium bulbs that give off an orange-yellow light. "Just as there are regulations and standards ...

Attention deficit disorders

Is ADHD really a sleep problem?

Around 75% of children and adults with Attention Deficit Hyperactivity Disorder (ADHD) also have sleep problems, but until now these have been thought to be separate issues. Now a in a pulling together of the latest research, ...

Health

I can't sleep. What drugs can I (safely) take?

If you're having trouble sleeping, medicines shouldn't be your first option. Exercise regularly, cut back on coffee (and other caffeinated drinks) after midday, eat less in the evening, ease up on "screen time" before, and ...

Health

New findings explain how melatonin promotes sleep

An estimated 50 to 70 million Americans have some type of sleep disorder, according to the National Sleep Foundation. Some turn to melatonin supplements to help them fall asleep. Melatonin is a hormone known to promote sleep, ...

Health

Preschoolers exposed to nighttime light lack melatonin

Exposing preschoolers to an hour of bright light before bedtime almost completely shuts down their production of the sleep-promoting hormone melatonin and keeps it suppressed for at least 50 minutes after lights out, according ...

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Melatonin

Melatonin i/ˌmɛləˈtoʊnɪn/, also known chemically as N-acetyl-5-methoxytryptamine, is a naturally occurring compound found in animals, plants, and microbes. In animals, circulating levels of the hormone melatonin vary in a daily cycle, thereby allowing the entrainment of the circadian rhythms of several biological functions.

Many biological effects of melatonin are produced through activation of melatonin receptors, while others are due to its role as a pervasive and powerful antioxidant, with a particular role in the protection of nuclear and mitochondrial DNA.

In mammals, melatonin is secreted into the blood by the pineal gland in the brain. Known as the "hormone of darkness," it is secreted in darkness in both day-active (diurnal) and night-active (nocturnal) animals.

It may also be produced by a variety of peripheral cells such as bone marrow cells, lymphocytes, and epithelial cells. Usually, the melatonin concentration in these cells is much higher than that found in the blood, but it does not seem to be regulated by the photoperiod.

Research has shown that when bird chicks ingest melatonin-rich plant feed, such as rice, the melatonin binds to melatonin receptors in their brains. No food has been found to elevate plasma melatonin levels in humans.

Products containing melatonin have been available over-the-counter as dietary supplements in the United States since the mid-1990s. In many other countries, the over-the-counter sale of this neurohormone is not permitted or requires a prescription, and the U.S. Postal Service lists unapproved melatonin preparations among items prohibited by Germany.

This text uses material from Wikipedia, licensed under CC BY-SA