Melatonin: Your Body's Sleep Signal
Melatonin is a hormone your brain naturally makes when the sun goes down. Think of it as your body's internal dimmer switch — when light fades, your pineal gland releases melatonin to tell your whole system it's time to wind down. People take it as a supplement to fix sleep problems, jet lag, or just to sleep better, and it's become one of the most popular over-the-counter pills worldwide because it actually works and has decades of research backing it up.
Here's what happens when melatonin enters your body: it latches onto specific receptors in your brain, particularly in a region called the suprachiasmatic nucleus — basically your brain's master clock. When melatonin docks there, it calms down nerve activity and nudges your circadian rhythm (your 24-hour internal schedule) to align with darkness. That's why it's especially useful for jet lag, helping reset your clock when you've traveled across time zones.
Beyond sleep, melatonin acts as a powerful cleanup crew in your cells. It scavenges free radicals — unstable molecules that damage cells — more effectively than vitamin E does. It also strengthens your immune system and helps your body fight inflammation. Research even shows it can make cancer cells more vulnerable to treatment while protecting healthy tissue.
Dosage Information
Typical Dose
0.5-5 mg for sleep, 10-50 mg for antioxidant/oncology research
Frequency
Once daily, 30-60 minutes before bedtime
Administration
Oral tablet, sublingual, or liquid
Half-Life
20–50 minutes
Notes
Lower doses (0.5-1mg) are often more effective for sleep onset than higher doses. Higher doses used in cancer research contexts are well above typical supplement doses.
Why this matters
Short half-life; timed-release formulations extend effect for sleep maintenance.
Protocol cycle
Where does Melatonin sit?
See how this peptide compares across all 150 peptides in our database.
Evidence Score
0.70
Compound Data
Molecular Formula
C13H16N2O2
Molecular Weight
232.28 g/mol
IUPAC Name
N-[2-(5-methoxy-1H-indol-3-yl)ethyl]acetamide
PubChem CID
896Potential Side Effects
Melatonin discussions
Quick Facts
- Administration
- Oral tablet, sublingual, or liquid
- Typical Dose
- 0.5-5 mg for sleep, 10-50 mg for antioxidant/oncology research
- Frequency
- Once daily, 30-60 minutes before bedtime
- References
- 0 curated + 45 from PubMed
- Clinical Trials
- 47 registered
- Evidence Score
- 0.7 / 100
Frequently Asked Questions about Melatonin
What is Melatonin?
Melatonin is a naturally occurring hormone produced by the pineal gland that regulates circadian rhythm and the sleep-wake cycle. It is also a potent antioxidant and has been studied extensively for roles in immune function, oncology, neuroprotection, and aging. Melatonin has one of the largest bodies of clinical research of any compound in this database, with hundreds of controlled trials across sleep disorders, jet lag, cancer adjunct therapy, and antioxidant applications. It is available over the counter in many countries and is one of the most widely used supplements globally.
How does Melatonin work?
Melatonin acts primarily through two G-protein-coupled receptors — MT1 and MT2 — found in the suprachiasmatic nucleus (the brain's master circadian clock) and peripheral tissues. MT1 receptor activation suppresses neuronal firing in the SCN, promoting sleep onset. MT2 receptor activation helps phase-shift circadian rhythms, making melatonin effective for jet lag and circadian rhythm disorders. Beyond sleep, melatonin is a potent direct free radical scavenger and stimulates antioxidant enzyme production — its antioxidant potency exceeds vitamin E on a molar basis. Melatonin also modulates immune function through effects on natural killer cells and T-lymphocyte activity, and has been shown in multiple cancer studies to sensitize tumor cells to conventional therapies while protecting normal tissue.
What is the recommended dosage for Melatonin?
The typical dose is 0.5-5 mg for sleep, 10-50 mg for antioxidant/oncology research. Once daily, 30-60 minutes before bedtime. Administration: Oral tablet, sublingual, or liquid. Lower doses (0.5-1mg) are often more effective for sleep onset than higher doses. Higher doses used in cancer research contexts are well above typical supplement doses.
What are the side effects of Melatonin?
Daytime drowsiness at higher doses (common). Headache (uncommon). Dizziness (uncommon). Vivid dreams (uncommon). Hormonal effects with long-term high-dose use (rare)
What is the Melatonin cycle protocol?
Melatonin is typically cycled as needed. Continuous nightly use typical for sleep support
Questions reflect common community inquiries. This is not medical advice.