What Is Valerian Root?
Valerian (Valeriana officinalis) is a flowering plant native to Europe and parts of Asia. Its root has been used medicinally since ancient Greece — Hippocrates described its properties, and it was used by Roman physicians for insomnia and nervousness. Today it's one of the most widely purchased herbal supplements in Europe, commonly sold for sleep and anxiety support.
Valerian's active compounds include valerenic acid, isovaleric acid, and a range of antioxidants including hesperidin and linarin. These appear to work primarily through the GABAergic system — the same calming neurotransmitter system targeted by benzodiazepines (like diazepam) and alcohol, though with far less potency and without the dependency risk.
What Does Valerian Actually Do?
Sleep Quality
Valerian is best studied for sleep. A 2006 systematic review of 16 eligible RCTs in American Journal of Medicine found valerian may improve sleep quality without producing side effects — though study quality was variable. More specifically:
- A 2011 double-blind RCT in postmenopausal women found 530mg valerian extract twice daily for 4 weeks significantly reduced insomnia severity and sleep quality scores
- A study in surgical ICU patients found valerian extract improved subjective sleep quality after one week
- Multiple studies show effects on sleep onset latency (time to fall asleep) and frequency of night waking
The effects are generally modest and less reliable than pharmaceutical sleep aids — but the safety profile is excellent, making it appropriate for long-term, low-risk use.
Anxiety
Valerian's GABA-modulating properties make it theoretically suitable for anxiety, and some human studies support this. A 2002 randomised study found valerian comparable to diazepam at reducing situational anxiety (assessed by physiological measures and self-report). A more recent animal study confirmed valerian extract significantly reduced anxiety-related behaviours via GABA-A receptor activity. Human data is promising but less robust than for sleep.
Menopause Symptoms
A 2011 RCT found valerian root significantly reduced the frequency and severity of hot flushes in menopausal women compared to placebo. Combined with its sleep effects, this makes valerian a reasonable consideration for the sleep disruption and anxiety commonly associated with perimenopause and menopause.
How to Take Valerian
For sleep: take 300–600mg of standardised valerian root extract (standardised to 0.8% valerenic acid) 30–60 minutes before bed. Unlike melatonin or pharmaceutical sleep aids, valerian tends to show stronger effects with consistent nightly use over 2–4 weeks — so give it time before evaluating results.
For anxiety: 120–200mg doses 2–3 times daily are used in clinical studies. This is a lower dose used across the day rather than the larger single bedtime dose for sleep.
Side Effects and Safety
Valerian is very well tolerated. Occasional reports of vivid dreams, mild drowsiness the following morning (at high doses), headache, or GI discomfort occur in a minority of users. Avoid combining with alcohol or pharmaceutical sedatives (additive CNS depression). There are rare reports of liver toxicity with very high doses — use recommended doses from reputable brands. Do not use during pregnancy without GP guidance.
Valerian vs Other Sleep Supplements
- Melatonin — most effective for circadian phase shifting (jet lag, shift work); less effective for general insomnia vs valerian in some comparisons
- Magnesium glycinate — excellent for sleep quality and relaxation; complements valerian well
- Ashwagandha — works via cortisol reduction; better for stress-related insomnia; slower-acting but more systemic
- L-theanine — promotes alpha brain waves and reduces anxiety without sedation; good for racing-mind insomnia
Valerian works best for generalised difficulty falling and staying asleep, particularly when anxiety is a contributing factor. It pairs well with magnesium glycinate and L-theanine for a comprehensive, non-habit-forming sleep stack. See our guide to sleep supplements UK for more comparisons.
Bottom Line
Valerian root is one of the most evidence-backed natural sleep aids available, with a particularly good safety profile for long-term use. Use a standardised extract at 300–600mg 30–60 minutes before bed, give it at least 2 weeks of consistent use, and consider combining with magnesium glycinate for a more comprehensive effect. It's a legitimate, gentle tool for sleep and mild anxiety — with centuries of use and growing clinical evidence behind it.