Melatonin
Your body's sleep-timing hormone — but most supplements sell it at 10–30× the dose you actually need. Less is more with melatonin, and it does far more than just help you sleep.
Melatonin is a hormone your brain makes when it gets dark — it tells your body "it's time to sleep." It's not a sleeping pill that knocks you out. It's a timing signal. And most people take way too much of it.
Good for you if: You have trouble falling asleep (but sleep fine once asleep), you're dealing with jet lag, your sleep schedule is shifted, or you want antioxidant benefits for aging.
Dive deeper into the researchWatch out for
- Morning grogginess — almost always from taking too high a dose (5–10 mg)
- Can interact with blood thinners, immunosuppressants, and diabetes medications
- May worsen depression at high chronic doses in some people
What does melatonin do?
Melatonin is not a sedative. It doesn't knock you out like a sleeping pill. Instead, it tells your brain "it's dark outside — start preparing for sleep." This triggers a cascade: your core body temperature drops, your metabolism slows, and your brain shifts into pre-sleep mode.
Your body makes melatonin naturally when it gets dark. The problem? Screens, LED lights, and late-night phone use suppress your natural melatonin production. A small supplement dose can help restore that signal.
Beyond sleep, melatonin is one of the most powerful antioxidants your body makes — it concentrates in your mitochondria and protects them from damage. Your natural melatonin production drops about 50% per decade after age 40, which may partly explain why aging accelerates.
What can you expect?
- Fall asleep 7–12 minutes faster — modest but meaningful, especially for circadian misalignment
- Jet lag recovery — this is melatonin's strongest use case, resetting your clock to a new timezone
- Better sleep consistency — more predictable sleep onset timing
- No grogginess — if you use the right dose (0.3–0.5 mg)
What melatonin does not do: it won't extend your total sleep time, improve deep sleep quality, or fix insomnia caused by anxiety or pain. For deeper sleep, magnesium glycinate is more effective.
How to take it
0.3–0.5 mg, 30–60 minutes before bed. This matches your body's natural melatonin peak. If you can only find 5 mg tablets (common in India), cut them into quarters.
Use situationally — jet lag, circadian disruption, occasional poor sleep — rather than every night. If using regularly, take a week off every month to let your natural production reset.
For jet lag: Take 0.5 mg at your destination's bedtime for 3–5 nights after eastward travel crossing 3+ time zones. This advances your internal clock.
Pair with: Dim lights and put away screens 1 hour before bed. Blue-light blocking glasses from 9pm onward may do more for natural melatonin production than any supplement.
Dose guide — less is more
| Dose | What it does | Recommended? |
|---|---|---|
| 0.3–0.5 mg | Matches natural peak; optimal for sleep onset | Yes — best dose |
| 1–2 mg | Moderately above natural; acceptable compromise | Okay if low-dose unavailable |
| 5–10 mg | 10–30× too high; morning grogginess likely | No — this is what most Indian stores sell |
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Get early accessFrequently Asked Questions
How much melatonin should I actually take?
0.3–0.5 mg, taken 30–60 minutes before bed. This matches your body's natural melatonin peak and works just as well as 5–10 mg tablets for falling asleep — with far fewer side effects. Most supplements sold in India are 5–10 mg, which is 10–30× too much. If you can only find 5 mg tablets, cut them into quarters.
Can melatonin cause dependence?
No physical addiction, but psychological dependence can develop with nightly use. High chronic doses may also suppress your brain's own melatonin production over time. Best approach: use it situationally (jet lag, occasional poor sleep, circadian disruption) rather than every single night. If using regularly, take a week off every month to check if you still need it.
Does melatonin work for jet lag?
Yes — jet lag is actually melatonin's strongest use case. For eastward travel crossing 3+ time zones: take 0.5 mg at your destination's bedtime for 3–5 nights. It works by resetting your internal clock to the new timezone. This is what melatonin was designed for by evolution — it's a timing signal, not a sleeping pill.
Is melatonin safe to take long-term?
At low doses (0.3–0.5 mg), melatonin is considered safe for most healthy adults with decades of data behind it. Long-term safety of high doses (5–10 mg) is less established. Avoid if you have clinical depression (may worsen mood at high doses), active autoimmune conditions, or are pregnant. Check for interactions with blood thinners and immunosuppressants.
How it works in your body
Melatonin is produced by the pineal gland from the pathway: tryptophan → serotonin → melatonin. Production is controlled by light — specifically, light hitting your retina suppresses melatonin via the suprachiasmatic nucleus (your master clock). This is why screens at night delay sleep onset.
Beyond circadian signaling, melatonin is a potent mitochondrial antioxidant. It crosses all cell membranes (including the blood-brain barrier), concentrates in mitochondria, and directly scavenges reactive oxygen species. In some experimental contexts, it's 10–100× more powerful than Vitamin E at protecting mitochondria.
Melatonin also upregulates your body's own antioxidant enzymes: SOD, glutathione peroxidase, and catalase. As natural production drops ~50% per decade from age 40, this protective function declines significantly.
What the studies show
- Sleep latency: Meta-analyses show melatonin reduces time to fall asleep by 7–12 minutes — modest but meaningful for circadian-type insomnia
- Total sleep time: Minimal effect — melatonin doesn't significantly extend sleep duration
- Jet lag: Strong evidence — consistently effective for eastward travel across 3+ time zones
- Dose-response: 0.3 mg is as effective as 5 mg for sleep onset latency, with significantly fewer side effects
- Antioxidant/longevity: Preclinical evidence for mitochondrial protection is extensive; human longevity data is observational
Side effects & safety
At the right dose (0.3–0.5 mg), side effects are rare. Most reported problems come from taking too much:
- Morning grogginess — Almost exclusively from 5–10 mg doses. At 0.3–0.5 mg, this is very rare.
- Vivid dreams — More common at higher doses. Usually not distressing but can be unsettling.
- Blood thinner interaction — Melatonin may slightly inhibit platelet aggregation. Monitor INR if on warfarin.
- Immunosuppressant interaction — Melatonin has immunomodulatory effects and may interact with cyclosporine.
- Depression concern — Some evidence that high chronic doses may reduce serotonin availability and worsen mood in susceptible individuals.
- Autoimmune conditions — Melatonin's immunostimulatory effects may exacerbate active autoimmune disease.
- Pregnancy — Insufficient safety data; avoid unless under physician guidance.
See the full melatonin side effects guide for detailed information.
Which labs to check
- Cortisol (morning) — High morning cortisol can override melatonin's effects and indicate a broader stress/sleep issue
- Vitamin D — Low vitamin D correlates with poor sleep; check alongside melatonin
- Thyroid panel — Thyroid dysfunction commonly disrupts sleep
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