Kava is among the best-studied botanicals for relaxation, and the strongest research support is for its use as an anxiolytic — that is, for easing everyday stress and tension. But reading the literature honestly means keeping two things apart: the quality of each study, and the quality of the kava that was tested.
The landmark review
The most-cited piece of evidence is the Cochrane meta-analysis by Pittler and Ernst (2000; updated 2003). Pooling multiple randomised, placebo-controlled trials, it found kava extract significantly better than placebo for anxiety symptoms, with adverse events that were mild, uncommon and short-lived. Most trials used the standardised extract WS 1490 and the Hamilton Anxiety Scale.
Closer to tradition
Later trials led by Jerome Sarris tested a water-based (aqueous) noble-kava preparation — much closer to what islanders actually drink. The 2009 KADSS trial and a 2013 trial in people with a formal generalised anxiety disorder diagnosis both found kava reduced anxiety versus placebo, and were generally well tolerated with no significant liver toxicity observed.
The honest caveat
The same group’s larger follow-up, published in 2020, did not find a statistically significant benefit for GAD. Taken together, the results mean the efficacy of kava for diagnosed anxiety is genuinely unsettled. The responsible reading holds both the encouraging and the disappointing findings in view — and, as always, this is educational context, not medical advice.
Last modified: July 14, 2026
