The main benefit of valerian is its usefulness as a sleep aid, but the herb is also associated with other potential benefits.
“Valerian appears to work by increasing GABA [neurotransmitter] brain activity, which is linked to a calming effect,” says Amy Chow, RD, founder of BC Dietitians, a database of nutrition experts in Langley, British Columbia.
Many potential benefits come from a handful of studies or those with small samples, so they are inconclusive.
It may improve sleep
Most people take valerian to help them sleep better. A small study of 72 adults with mild insomnia found that 200 milligrams (mg) of valerian extract taken one hour before bed for eight weeks led to significant improvements in the time it took participants to fall asleep, their overall sleep time, and the percentage of time spent sleeping while lying down. Researchers also noted that those who used valerian experienced less anxiety and daytime sleepiness and reported feeling more refreshed.
“While there is subjective support for [possible] valerian’s sleep-enhancing properties, such findings could not be replicated quantitatively or objectively,” says Staci Gulbin, RDN, founder of Lighttrack Nutrition in Denver and former researcher at the U.S. Department of Agriculture (USDA).
In fact, a review of eight systematic reviews found that valerian did not significantly improve insomnia. But a significant amount of research on valerian is conducted on animals.
“More randomized, controlled human studies are needed to confirm the sleep benefits of valerian,” says Gulbin.
It can ease hot flashes and PMS
Valerian may ease the side effects of hormonal problems in women, including hot flashes, a common symptom of menopause. In a small study of 60 postmenopausal women aged 45 to 55, one group took a 530 mg capsule of valerian twice daily for two months, and the other took a placebo. The valerian group saw a significant reduction in the severity of their hot flashes.
Valerian root extract may also help treat symptoms of premenstrual syndrome (PMS). In a small study in Iran of 100 women aged 20 to 30, researchers found that emotional, behavioral and physical symptoms improved after participants took 530 mg of valerian twice daily for the last seven days of their menstrual cycle, according to older research. However, research on the potential benefits of valerian for women experiencing PMS or menopause is limited. “Larger human studies could provide more evidence of the potential health benefits of valerian,” adds Gulbin.
It can relieve anxiety and depression
A study involving patients with advanced kidney disease undergoing hemodialysis found that taking valerian root an hour before sleeping for a month led to decreased symptoms of anxiety and depression, as well as improved sleep quality.
“The limitations are that this is a small sample in a very specific population,” says Laura Craig, MD, a Chicago-based board-certified psychiatrist and founder of Betula Mental Health. Researchers also assessed symptoms associated with anxiety and depression compared to directly studying people with anxiety or depressive disorders, she adds.
In his practice, Dr. Craig recommends valerian primarily for sleep problems, but says it can also relieve mild anxiety. “But there is little evidence to support its use in depression,” she notes.
