Valerian has one of the longest continuous medicinal histories in Western herbalism, documented by both Hippocrates and the Roman physician Galen for its calming, sleep-inducing properties. Its name is believed to derive from the Latin "valere," meaning "to be strong" or "to be well," reflecting its broad traditional reputation as a general tonic in addition to a sleep aid.
The root has a famously strong, somewhat unpleasant odor once dried, often compared to old socks or cheese — a curious contrast to its calming reputation that has been remarked upon by herbalists for centuries. Valerian became one of the most widely used herbal sleep aids in Europe by the 19th century and remains among the best-selling herbal supplements in Western markets today, which makes the honest state of its clinical evidence particularly worth knowing.
Valerian is a genuinely instructive case of a very popular remedy whose rigorous evidence hasn't kept pace with its popularity. Multiple independent systematic reviews spanning two decades have reached strikingly consistent conclusions: a 2000 review of 9 trials found contradictory results, a 2006 meta-analysis of 16 studies (1,093 patients) found methodological problems throughout the literature, and a 2010 meta-analysis of 18 trials concluded valerian's effectiveness "had not been demonstrated with quantitative or objective measures."
A 2024 umbrella review — a review of reviews, considered a particularly high level of evidence synthesis — examined 8 eligible systematic reviews and reached a clear verdict: valerian has a good safety profile, but there is no evidence of efficacy for insomnia when measured objectively (sleep studies, actigraphy), even though people using it subjectively often report feeling their sleep improved. This gap between subjective feeling and objective measurement is common in sleep research generally, but is particularly pronounced and consistently documented for valerian specifically, which is why "Limited" — rather than higher, despite valerian's enormous popularity — is the accurate rating here.
Dried root steeped as tea (though its strong odor makes this less popular than other forms), or ground into capsules and tinctures.