What Does Science Say About Kava?

Kava has peaked the interest of researchers in recent years due to its many noted benefits, particularly its ability to reduce stress and anxiety.

However, there is growing evidence that kava may also have other important health benefits. For example, a 2000 study found that the more kava a population consumed, the lower the cancer incidence for that population, despite high tobacco use.

Some evidence also suggests that kava may have anti-inflammatory properties.

Reviewing Kava’s Benefits

In a recent review, published in the journal Nutrients, researchers looked at the history of kava and kava bars, as well as its chemical properties, anti-inflammatory potential, the effects it has on the brain, anti-cancer properties, and issues relating to its safety.

The following information features a few highlights based on their findings. You can find the whole review here.

Increase in kava bars

Kava bars began in New Caledonia, a French territory consisting of numerous islands in the South Pacific (near Australia). The idea came to fruition because young people wanted to have a place to meet and relax without drinking alcohol.

These bars later expanded to Hawaii and other islands in the Pacific and then on to Western nations. In the United States, the number of kava bars increased by approximately 30% from 2012 to 2017, according to the review.

Anti-inflammatory properties

Inflammation plays an important role in the development of many types of diseases, from cancer to brain disorders. 

Previous studies have investigated kava for its anti-inflammatory properties. These studies were at least partly prompted by kava’s analgesic (pain-relieving) effects. This is because anti-inflammatory drugs are widely used for pain relief.

In addition, kava has traditionally been used “for the treatment of urinary tract infections and immune-related disorders, such as asthma.”  

According to the review, several studies had found that natural kavalactones, particularly kavain, showed significant anti-inflammatory effects in numerous animal studies.

Addiction, Anxiety and Insomnia 

The review found that kava has been used as part of addiction rehabilitation programs in New Zealand with a 90% reported success rate. 

Kava consumption has also been reported with improvements in memory tasks as well as greater accuracy and performance in visual attention. 

Evidence has also shown the benefits of kava when it comes to sleep, with reports of increased deep sleep periods and sleep spindle activity (bursts of brain activity during sleep).

“As sleep disorders are common in the general population, particularly in various neuroinflammatory and neuropsychiatric disorders, kava’s sleep-improving effects warrant further investigations in future research,” write the researchers.


Research on the potential anti-cancer properties of kava have been fueled by the observations that populations who regularly consume kava have reduced rates of cancer.

“Nations with high kava consumptions, such as Vanuatu, Fiji and Western Samoa, have had much lower age-standardized cancer incidence rates in comparison to the rates in non-kava-drinking countries,” write the researchers. 

“Intriguingly, men in these regions had lower incidence rates of cancer than women, which is opposite to the general trends in other parts of the world; given that kava is mainly consumed by men, this observation is consistent with kava’s potential in reducing cancer risk.”

These observational findings have been supported in lab research. For example, kava and its components have shown preventive activity against carcinogen-induced tumors in several lab animal models. This includes lung tumors as well as prostate and colon cancer.

In addition, traditional kava — alone or combined with sea hibiscus — has demonstrated anti-cancer activity against breast and colon cancer cells as well as reduced prostate tumor growth.

The above information is based on this review.

Other research


Kava may help reduce insomnia, often with fewer side effects than pharmaceutical drugs or over-the-counter sleep enhancers. It is noted that a specific type of kavalactone, called kevain, may be behind kava’s sedative effects.

In a pilot study of 24 patients with stress-induced insomnia , a research team investigated the effectiveness of kava and valerian separately. Stress was measured in three areas: social, personal and life events. Insomnia was also measured in three areas: time to fall asleep, hours slept and waking mood. 

According to the findings, total stress severity was significantly reduced by both compounds individually, with no significant differences between them. There was also improvement with the combination, significantly in the case of insomnia.

“These results are considered to be extremely promising but further studies may be required to determine the relative roles of the two compounds for such indications,” write the authors.


If you were to walk into a kava bar and ask regular kava consumers why they drink kava, a large majority would probably say it helps them relax and that it reduces their anxiety. 

Research is catching up on these anecdotes.

In a double-blind, randomized, placebo-controlled study, a research team examined the effectiveness of kava on patients with generalized anxiety disorder (GAD). 

A total of 75 participants were enrolled in a 6-week trial of a kava extract versus placebo. The findings revealed a significant reduction in anxiety for the kava group compared with the placebo group. 

According to a 2002 review of seven clinical trials and 645 people, a kava extract was found to be an “effective symptomatic treatment option for anxiety.” Safety and tolerability were also good, with no drug-related adverse events, according to the authors.

The fact that kava helps with anxiety is welcome news for many people searching for a natural alternative to pharmaceutical anxiety medications, which can be wrought with side effects. While everyone experiences stress and anxiety to an extent, millions of Americans struggle with clinical levels of anxiety. 

Anxiety disorders are the most common mental illness in the U.S., impacting 40 million adults age 18 and older, or 18.1% of the population each year, according to the Anxiety and Depression Association of America (ADAA). 

What are the side effects of kava?

As with any substance, overdoing it can lead to problems. Long-term use can lead to dry scaly skin in some people. Some side effects of kava may include mouth numbness (common), drowsiness, headache and indigestion. It is highly recommended that alcohol use be avoided when consuming kava. 


Similar Posts

Leave a Reply