We routinely see people reporting what they feel are liver issues when drinking kava; however, the reality is that few if any of these self-reports are actually due to liver issues in conjunction with drinking kava. We usually see this as due to either gas pains or digestive issues that may not have anything to do with kava consumption.
How would you identify actual liver damage?
Without exception, no matter where you feel that pain or ache, no matter what color your urine is, you must undergo a metabolic test to claim any type of liver issue. This test tests for levels of Alanine Aminotransferase (ALT), and Aspartate Aminotransferase (AST) in your blood. This is a test in which a blood sample is drawn to the laboratory. See the attached sample comprehensive metabolic test [1].
As you can see from the sample metabolic test, among the other values listed, they also show AST/ALT. In this sample test, these values are slightly elevated, but at what point are they an issue? When interpreting a liver test, it is generally thought that ALT values more than 3 times the upper limit of normal will indicate liver damage (or around 165) [2]. ALT and AST will be indicators of liver damage if any has occurred. It is important to understand that this is necessary because visual and pain indicators are not a good way to determine liver function issues. These values can be altered by a vast number of over-the-counter and prescription medicines.
Kava has endured a legacy of intense scrutiny, and of this scrutiny, only a handful of cases were more than likely tied back to kava usage. Another important aspect to understand is that these findings apply specifically to the use of ethanolic and acetonic extracts. The use of kava as a traditional social beverage has not been implicated in similar ways, except in one case. There were two reports of injury from aqueous kava in New Caledonia; however, all of these reports included extreme elevations in AST values [4], which is not only uncommon but also unheard of in standard kava drinking. GGT/ALP are the values most often altered by kava. It is more than likely that these instances were due to co-medication, alcohol consumption, or other unknown factors. It is also well known that at the time of the injury reports, the kava being imported into New Caledonia from Vanuatu was of the non-noble or non-beverage grade type. This poor quality product may be an “unknown factor” in these cases.
In summary, if you think you have a liver issue, go to the doctor; however, it should be understood how rare these issues actually are. We are still being held up by cases that happened 23 years ago. The likelihood of having a liver issue due to kava is extremely rare; however, if you have any question about whether your liver is in good health, a metabolic test is the only way to tell. Without a test, it is impossible to determine if you have experienced an injury. My personal opinion, and what I do myself, is that for my yearly physical examination, I ask for a metabolic test. So far, my AST/ALT values have not moved outside the normal range in more than 16 years of daily traditional kava drinking at 40g/day. This is a sample size of one, so certainly not do I make a perfect representation of kava consumption; however, you’ll find many long time kava drinkers with the same story.
[1] Health and wellness testing example results | health testing centers. (n.d.). Retrieved June 1, 2021, from https://www.healthtestingcenters.com/health-and-wellness-testing-example-results/
[2] Fancher, Tonya, Amit Kamboj, and John Onate. 2017. “Interpreting Liver Function Tests.” Current Psychiatry 6 (5): 61–68. https://cdn.mdedge.com/files/s3fs-public/Document/September-2017/0605CP_MedPsych.pdf
[3] “Re: Critical Analysis of Suspected Cases of Kava Hepatotoxicity: Kava Taken as Directed Is Rarely Hepatotoxic - American Botanical Council.” n.d. Accessed May 10, 2021. https://www.herbalgram.org/resources/herbclip/issues/bin_368/review120381-368/.
[4] Russmann, Stefan, Yann Barguil, Pierre Cabalion, Marina Kritsanida, Daniel Duhet, and Bernhard H. Lauterburg. 2003. “Hepatic Injury due to Traditional Aqueous Extracts of Kava Root in New Caledonia.” European Journal of Gastroenterology & Hepatology 15: 1033–36. https://doi.org/10.1097/01.meg.0000085464.12407.7b.