Can Valerian Root Help You Sleep?

Insomnia is a serious problem. Not only does it affect your quality of life and ability to function, but insufficient sleep also is associated with a higher risk of a range of health problems, including type 2 diabetes, heart disease, obesity, and depression. Blame for insomnia often falls on modern phenomena like late-night screen time, which is reportedly capable of disrupting our circadian rhythms. But people struggled with insomnia long before we had TV or Twitter, and although we’re now fortunate to have help from modern sleep science, some other insomnia remedies may still be useful.

Valerian root, for example, has been used as a medicinal herb for thousands of years, with a reputation as a sleep aid dating back at least to ancient Greece. It’s often sold in supplement form. However, we are still learning how (and how well) it really works. Here’s a closer look at what research has revealed about using valerian root for sleep.

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What is valerian?

The genus Valerian is part of the honeysuckle family, with more than 250 species native to Eurasia and the Americas. Despite this diversity, the word “valerian” is widely used as the common name for a single species: Valeriana officinalis, also known as garden valerian. Native to Eurasia (and now naturalized in North America), garden valerian has a distinctive scent that people often find unpleasant, sometimes likened to sweaty socks.

That odour wasn’t enough to repel humans entirely, though, and eventually someone realized valerian is more than just a stinky pink flower. The key to valerian’s fame lies underground, where its roots and rhizomes produce a unique mix of acids, oils, and other compounds with reputed sleep benefits. These are harvested and then processed to create valerian root supplements.

Can it really improve sleep?

Valerian root may be famous for its sedative effect, but research into claims of better sleep has yielded inconclusive results overall, according to the U.S. Office of Dietary Supplements (ODS), part of the National Institutes of Health. Some studies do support valerian’s reputation for helping people sleep, but others do not, leaving too little clarity for firm conclusions. Many of the studies that link valerian to better sleep also have methodological limitations, explains Stephen Bent, MD, a board-certified internist and a professor of medicine at the University of California San Francisco.

Dr. Bent’s research focuses on evaluating the safety and efficacy of herbal remedies and dietary supplements. He led a systematic review and meta-analysis of valerian’s sleep effects in 2006, which was published in the American Journal of Medicine. “It appears to be safe, and it may be reasonable to try on an intermittent basis to help improve sleep,” Dr. Bent says. But talk with your doctor first, he adds. That’s a smart move when it comes to any new supplement, even if it’s generally considered safe.

“I recommend that patients always discuss this treatment with their primary care doctor to consider whether there may be interactions with their medications or other considerations,” he says. “I also always recommend a trial of nonmedical interventions to improve sleep prior to any supplement or medicine.” Valerian root is sometimes credited with a calming effect, yet while some people take it for anxiety relief, that may be even less supported by science than its use as a sleep aid. “There is very limited evidence regarding the efficacy of valerian for anxiety,” Dr. Bent says. “There are other medical and nonmedical treatments for anxiety that have proven very effective.”

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What’s in valerian root?

We still have a lot to learn about the compounds in valerian root and how they affect the human body. There is no scientific agreement about valerian’s active constituents, according to the ODS, which notes that “its activity may result from interactions among multiple constituents rather than any one compound or class of compounds.” Valerian root features essential oils, including its namesake valerenic acids, which have a sedative effect. These are thought to be at least partly responsible for valerian root’s potential sleep benefits, although research suggests multiple compounds likely work together to create the effect.

Valerian root has other interesting compounds, too, including phytochemicals called iridoids and a group of flavonoids called flavonones. One standout is gamma-aminobutyric acid (GABA), an amino acid that acts as a neurotransmitter. While it’s unclear whether GABA crosses the blood-brain barrier, valerian root seems to also boost GABA availability in other ways, like inhibiting a GABA-destroying enzyme in the brain. “There is some evidence to suggest that valerian decreases the metabolism of [GABA], leading to higher GABA levels in the brain, which may reduce feelings of stress or anxiety,” Dr. Bent explains.

How to take valerian root

Valerian root supplements come in a few different forms, including extracts as well as capsules, teas, and tinctures made from the dried roots. The quality and dosing may vary widely from source to source, a common issue with many herbal supplements. As Dr. Bent and his coauthors reported in their research review, there is also a wide variation of dosages used in many studies of valerian root for sleep. In their review, the doses ranged from 225 milligrams to 1,215 mg per day.

Doses vary even more for valerian products sold in the United States: among 13 products tested, the recommended dose ranged from 75 mg up to 3,000 mg per day, the researchers found. Given the variability in valerian supplements and the lack of clarity from research, it may be helpful to ask your doctor about dosing, along with any other questions about risk. As for timing, valerian root seems to be most effective as a sleep aid when taken shortly before bedtime.

(Related: 10 Science-Backed Ways to Get More Shut-Eye)

Potential risks or side effects

Valerian root is sold as a dietary supplement in Canada and the United States, so while it is regulated by the Food and Drug Administration (FDA), it’s regulated more like a food than a drug. Unless a valerian root product claims to prevent or treat specific diseases, it doesn’t need FDA testing or approval before it’s sold—part of the reason why doses vary so much. Clinical studies of valerian root have found few adverse effects, though you may experience headaches, dizziness, itching, and gastrointestinal issues.

Valerian root itself seems to be safe for most people, according to the ODS, although it should not be taken by women who are pregnant or nursing, or by children younger than 3 years old. There are some rare reports of liver toxicity in people who took valerian root, Dr. Bent notes, but it’s unclear whether that was caused by valerian or by some contaminant in the product. And because herbal supplements in the United States have “very limited regulation by the FDA,” he adds, “I recommend patients use reputable brands from well-known manufacturers.” Look for a seal that ensures a product has been tested by a third party. That’s just one more step you can take to make sure you’re buying the safest product possible.

Valerian root vs. melatonin

Valerian root could have adverse effects if taken in combination with other sedative medications or supplements, the ODS warns. This includes benzodiazepines like Xanax or Valium; barbiturates and other central nervous system depressants, such as alcohol; and certain dietary supplements, like kava, melatonin, and St. John’s Wort. You should not combine valerian root with other sleep aids or sedatives, like melatonin, at least not without seeking expert guidance first.

“Theoretically, it is possible that multiple supplements that promote sleep could lead to oversedation,” Dr. Bent says. “It would be important to discuss the use of these treatments with a primary care doctor.” If you get your doctor’s go-ahead, you can give valerian a go. Swallow a capsule or drink some tea before bed, then hopefully drift off into an uninterrupted slumber.

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