Melatonin
Low dose, USP-verified
Strong
Several good studies agree
Strong for sleep onset: 19 RCTs, n = 1,683, consistent direction, dose-response established. Marked Tier B for wearables because a 7-minute shift sits inside sensor noise.
Across 19 studies it helped people fall asleep about 7 minutes sooner and sleep about 8 minutes longer. Real, but too small for a watch or ring to pick up. It helps most when your body clock is off, like after a flight.
Melatonin reliably helps people fall asleep a little sooner — about seven minutes in the benchmark meta-analysis — and adds around eight minutes of sleep. The effect is real, but smaller than the night-to-night variation your wearable already shows, so don't expect your sleep score to move. Where it shines is shifting your body clock: jet lag, late chronotypes, shift work.
Signals 'biological night' to the suprachiasmatic nucleus via MT1/MT2 receptors — a timing cue rather than a sedative.
Circadian problems (jet lag, delayed sleep phase, shift work). Start at 0.5–1 mg; more is not better. Choose third-party-tested products — measured content ranged from −83% to +478% of the label.
We compare each effect with how much that number normally swings from one night to the next. An effect smaller than the swing is real, but you will not see it in a week of data.
- Sleep onset latencyVisible over weekseffect: 7.06 minnormal swing: ±20 min
- Total sleep timeToo small to seeeffect: 8.25 minnormal swing: ±50 min
What to buy
- ✓Low dose: 0.5–1 mg
- ✓USP Verified mark (content accuracy problem is real)
- ✕5–10 mg 'extra strength' — more is not better
- ✕Gummies (content variability)
- · Label accuracy problem (−83% to +478% of stated dose) — choose third-party-tested.
- · Interacts with anticoagulants, contraceptives, immunosuppressants.
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Physiologic dose with verified content.
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0.5 mg is the physiologic dose — close to what your own body releases. The 5 and 10 mg products that dominate the shelf are far above anything the trials needed, and more melatonin does not mean more sleep.
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See all on AmazonEvery result, next to the line that means no effect
Each diamond is a study's best estimate. The thin line shows how sure the study was: the shorter the line, the more certain the result.
- Sleep onset latencymin · Ferracioli-Oda 2013−7.06−8.98 … −5.13
- Total sleep timemin · Ferracioli-Oda 2013+8.25+1.74 … +14.8
Each unit gets its own scale, so numbers are never mixed on one line. When a study gave no range, we leave it blank instead of inventing one.
2 studies over 4 years
The studies
- 1.Meta-analysis: melatonin for the treatment of primary sleep disordersPLOS ONE · 2013 · meta-analysis · 19 experiments · n = 1,683
Sleep onset −7.06 min, total sleep +8.25 min, modest subjective quality gain.
- 2.Melatonin natural health products and supplements: presence of serotonin and significant variability of melatonin contentJournal of Clinical Sleep Medicine · 2017 · cohort · n = 31
Content ranged from −83% to +478% of label; 26% contained serotonin.
Umbral is a wellness product, not a medical device. It does not diagnose, treat, cure or prevent any disease. Supplement information is educational; talk to a clinician before starting anything, especially if you are pregnant, under 18, managing a condition or taking medication.
These statements have not been evaluated by the Food and Drug Administration.