Does valerian root help with sleep? What the research does and doesn't show

The evidence doesn't support valerian root as a treatment for insomnia. Systematic reviews disagree with each other on whether it beats a placebo at all, and the pattern across them is consistent: the more rigorous and recent the trial, the less likely it is to find a significant effect on sleep.

What the evidence doesn't support

It doesn't support valerian root, in any form or dose, as a treatment for insomnia or any other diagnosed sleep disorder. It doesn't support a specific, reliable time-to-fall-asleep benefit, and it doesn't support using it in place of evaluating or treating a persistent sleep problem. Nothing below is proof that a given capsule, tea, or tincture will make a person fall asleep faster or sleep more soundly.

What the trials found

A 2024 umbrella review of 8 systematic reviews on valerian for insomnia concluded that valerian has a good safety profile but does not have empirical support for treating insomnia when judged by quantitative or objective sleep measures — despite widespread use and being commonly recommended. Valerian appeared to help with subjective sleep-quality ratings in some of the reviews it summarized, but that effect wasn't confirmed with objective measurement tools (PMID 38359657).

A 2007 systematic review of 37 valerian studies reached a similar conclusion in its own title: "safe but not effective." Most studies found no significant difference between valerian and placebo in healthy people or people with general sleep disturbance or insomnia, and the most recent, most methodologically rigorous trials in the review found no significant effect on sleep at all (PMID 17517355).

A 2006 meta-analysis pooled 16 randomized, placebo-controlled trials — 1,093 people in total. Using a simple yes/no measure of whether sleep improved, valerian showed a statistically significant benefit over placebo (relative risk 1.8, 95% CI 1.2-2.9), but the authors found evidence of publication bias in that specific result, and doses across the pooled trials varied widely, from 225 mg to 1,215 mg a day (PMID 17145239).

A 2010 meta-analysis of 18 placebo-controlled trials found a similar split. On the same kind of simple improved/not-improved measure, valerian showed a modest benefit (relative risk 1.37, 95% CI 1.05-1.78). But on the two measures that used numbers instead of a yes/no answer — time to fall asleep and a standardized sleep-quality scale — there was no significant difference from placebo (mean difference 0.70 minutes for sleep onset; standardized mean difference -0.02 for sleep quality). The review's authors concluded that valerian's effectiveness hadn't been demonstrated with quantitative or objective measurements (PMID 20347389).

A 2020 systematic review pooled 10 trials (1,065 people) that used repeated dosing and numeric sleep-quality outcomes; the combined effect was small and not statistically significant (Hedges' g 0.36, 95% CI -0.08 to 0.81). Splitting those same 10 trials by preparation, whole dried root scored higher (0.83, 95% CI 0.03 to 1.62) than concentrated extract (0.10, 95% CI -0.02 to 0.22) — a difference the reviewers flagged as a possible explanation for inconsistent results elsewhere in the literature, though that whole-root subgroup was only 4 small trials with a wide confidence interval, not a settled finding. Individual trials in that same review varied just as widely: a web-based trial of 405 people with trouble sleeping found a modestly better global self-rating after 600 mg a day for 14 days (p=0.04); a smaller trial of 16 older women found no significant difference from placebo on sleep-lab measurements or self-rated sleep after 300 mg a day for two weeks; and a trial of 14 elderly poor sleepers found a single 405 mg dose had no measurable effect, while the same dose taken three times a day for a week changed some sleep-stage measurements without improving how quickly people fell asleep or how they rated their own sleep quality (PMID 33086877).

Questions people ask

Does valerian root help you sleep?

The reviews disagree with each other, and that disagreement is itself informative: the more rigorous, more recent, and more objective the measurement, the less likely a trial is to find a significant effect. The most recent umbrella review of the whole field found no empirical support for treating insomnia with it.

How much valerian root should I take for sleep?

Trial doses ranged from 225 mg to 1,215 mg a day, and a survey of commercial US products found labeled doses from 75 mg to 3,000 mg a day — a wide range with no dose shown to work reliably better than another. One trial comparing 300 mg and 600 mg against placebo found more reported drowsiness at the lower 300 mg dose, so higher isn't consistently worse either. See how much valerian root should you take a day? for the full dosing research.

When should I take valerian root for sleep?

Most sleep trials dosed valerian 30 minutes to an hour before bedtime, a study-design choice rather than a tested "best" timing against alternatives. See when is the best time to take valerian root?

How long does valerian root take to work?

Results were inconsistent even within a single trial: one study found a single dose changed some sleep measurements at home but not in a sleep lab, and repeated dosing over a week changed sleep-stage measurements without improving how quickly people fell asleep. See how long does valerian root take to work? for a focused look at onset.

Does valerian root cause insomnia or make sleep worse?

No trial reviewed here found valerian worsening sleep while it was being taken. Separately, published case reports describe cardiac complications and delirium after people abruptly stopped long-term, high-dose valerian use (PMID 9820254, PMID 32576405) — a withdrawal effect, not evidence that valerian itself disrupts sleep while in use.

Is whole root or extract better for sleep?

A subgroup analysis found whole dried root numerically outperformed extract in pooled sleep-quality trials (0.83 vs. 0.10), but that whole-root result came from only 4 small studies with a wide confidence interval — a lead, not a settled answer (PMID 33086877).

Valerian root vs. melatonin for sleep?

See valerian root vs melatonin for a dedicated comparison of the two.

Is magnesium or valerian root better for sleep?

No trial directly compares the two head-to-head for sleep. Each has its own separate evidence base, and this page doesn't have a research basis to rank one against the other.

When to talk to a doctor

Ongoing trouble falling or staying asleep, especially if it affects daytime functioning, is worth raising with a doctor — insomnia has treatments with real evidence behind them, and valerian root, based on the research above, isn't established as one of them. If you take a sedative, sleep medication, or other prescription drug, or are pregnant or nursing, talk to a doctor before adding valerian in any form.

Related reading: how much valerian root should you take a day?, when is the best time to take valerian root?, how long does valerian root take to work?, and valerian root vs melatonin.