Researchers pooled 26 double-blind trials comparing melatonin with placebo in adults with insomnia and in healthy volunteers. Melatonin shortened the time taken to fall asleep and lengthened total sleep time, with the strongest effect around 4 mg per day. Taking it about 3 hours before the target bedtime worked better than the 30 minute gap most often used in practice.
Melatonin is a hormone the body releases at night. It is also sold and prescribed for trouble sleeping, and trials of it disagree. The authors suspected the disagreement came from how the trials were run. Published studies have used doses from 0.1 mg to 10 mg, given anywhere from bedtime itself to three and a half hours before it. No previous review had asked which dose and which timing produce the largest effect in adults.
This was a systematic review and dose response meta analysis: the authors pooled existing trials, then modeled how the effect changed as dose and timing changed. They searched MEDLINE up to March 2021 and included only double blind, fixed dose, randomized controlled trials in adults over 18 comparing melatonin with placebo. Participants were healthy volunteers or people with primary insomnia. Children, shift workers, other sleep disorders and doses above 10 mg per day were excluded.
Twenty six trials published between 1987 and 2020 met the criteria, giving 1689 observations. The outcomes were sleep onset latency, the time taken to fall asleep, and total sleep time.
Across 25 trials, melatonin cut the time to fall asleep by 9.31 minutes against placebo (95% CI 6.19 to 12.43 minutes, p less than 0.001, I squared 49.9%). Across 19 trials, total sleep time rose by 19.67 minutes (95% CI 12.35 to 27.00 minutes, p less than 0.001).
The dose response model predicted both effects peak at 4 mg per day, with no gain above that. Against the 2 mg dose commonly used in practice, 3 mg and 4 mg were significantly better for sleep onset (p less than 0.001 and p equals 0.004); 5 mg was not (p equals 0.17).
Timing mattered. Taking melatonin 1 hour before sleep was no better than at bedtime (p equals 0.57), but 2 hours and 3 hours before both produced significant reductions (p equals 0.01 each). The model predicted a 19.62 minute reduction at 3 hours against 3.45 minutes at bedtime. Melatonin also worked less well in people with insomnia than in healthy volunteers.
The average benefits are small: roughly nine minutes to sleep onset and twenty minutes of sleep. Egger's test found funnel plot asymmetry for sleep onset latency (p equals 0.015), pointing to possible publication bias. Only two included trials gave melatonin earlier than 3 hours before sleep, so the curve beyond that point is unsettled. The optimal dose and timing are model predictions, not results of a trial that tested them, and the authors say replication is essential.
One author, U. F., is cofounder and president of Sleepacta S.r.l., a University of Pisa spin off working in sleep medicine. The others declared no conflicts. Funding came from the Arpa Foundation, the Italian Ministry of Health and a voluntary contribution to IRCCS Stella Maris, not from a supplement company.
Read this as hypothesis generating. It suggests the common arrangement, 2 mg about half an hour before bed, may not produce the largest effect. It does not show that, because no trial in the review directly compared 4 mg at three hours against 2 mg at thirty minutes.
The review covered healthy adults and people with primary insomnia only. It says nothing about children, shift work, jet lag or any other sleep disorder, and the authors state that limit themselves. The effect was weaker in the insomnia group than in healthy volunteers, so this clinical population did worse here, not better.
That depends on the specific medication and formula. A few, like blood thinners with CurQLife or blood pressure medication with MaxiNOs, are worth a direct conversation with your doctor first. Check each formula's own FAQ section for specifics, or ask your health coach.
No, and we'd rather be upfront about it. Bacopa, the plant in BacoZest, has published human studies, though they used other bacopa extracts. OptiNOs and MaxiNOs each have human studies sponsored by their maker, Laila Nutraceuticals, which haven't been published in a journal. CurQLife's research is still early, from lab and animal studies, and we label it that way.
It depends on what you're building your routine around. BacoZest is built around bacopa, which is studied for memory.* OptiNOs supports strength and muscular endurance alongside resistance training.* MaxiNOs was studied for healthy blood vessel function.* CurQLife's research is still at the lab stage. Your health coach can help you pick a starting point.
All four are built around plant extracts. OptiNOs was reported as well tolerated in its human study, and published bacopa studies reported no serious side effects. CurQLife's safety data so far comes from lab and animal testing. Check with your doctor first if you're pregnant, nursing, on medication, or managing a health condition.
Because the patented ingredients behind our four formulas went through dedicated research, and research costs real money. A generic curcumin or bacopa supplement hasn't been tested in the form you get from us. You're paying for an ingredient with research behind it, not just a label.
Generic ingredients often haven't been studied in the specific form you're buying. Our four core formulas use patented ingredients, and we show you the research behind each one, including where it's still early.
It depends on the formula. In its study, MaxiNOs blood vessel response was higher than placebo 2 to 3 hours after the first dose.* OptiNOs and bacopa were studied over 6 and 12 weeks of daily use, so give them time. CurQLife is meant to be taken daily.
Yes. BacoZest, OptiNOs, MaxiNOs, and CurQLife are built for different goals, and none of them contain stimulants. They haven't been studied together, so ask your health coach how to fit them into your routine.
