Kava, with caveats: is this popular psychoactive tea bad for your liver?

After years of research, it's still unclear if the South Pacific plant is toxic

26

The first time I tried kava, I gagged — and then a few minutes later, I was bonelessly relaxed. I was at Kavasutra, a small kava bar in the East Village in Manhattan, where my eyes were often caught by a big, bright TV displaying weird videos about bugs. I had heard about kava from some friends, who liked to go to Kavasutra after work to wind down at the end of a long day.

As a hard-working Manhattanite who over-stresses about pretty much everything, of course I wanted to try the drink, which promises relaxation. The bartender at Kavasutra suggested I try a cup of concentrated kava — recommended for your first Kava Experience, the menu says — and chug it down as quickly as possible. That proved very difficult to do.

When the ground or powdered kava root is mixed with water, it turns into a brownish-grayish drink that looks very much like a dirty puddle. The taste is even more upsetting: earthy and bitter — just what I think drinking a mouthful of mud would be like. I had to take a break after a few sips, because my stomach was churning. Suddenly, my mouth felt numb, as if I’d just been to the dentist to get another root canal.

Grounded kava root Amelia Holowaty Krales

Because I was new to kava, the bartender told me I had to drink a little more than just a cup to get the relaxation effect I wanted. (Some people report having a "reverse tolerance" — after drinking kava for a while, they need a smaller dose to achieve a psychoactive effect.) So I ordered another one and painstakingly swallowed it down, until I could finally feel my muscles relax. Suddenly, the stress of the day was taken off my shoulders and I felt more social, careless. I had taken a legal stress-reliever that didn’t blur my vision and create bad decision-making; I’d swallowed a milder, prescription-free version of a Xanax.

Kava is a plant from the South Pacific; the drinks made from its root have been consumed for centuries for their anti-anxiety and euphoric effects. And that’s what makes kava still popular around the world today. As interest in kava has grown, several kava bars have popped up all over the United States. (Though no good data exists on kava use, experts say that kava popularity has increased in the US.) But the plant has a troubled past and a murky safety record. Kava consumption has been associated with liver injury in the US and Europe. Despite years of research, scientists are still unsure about what in the plant, if anything, is toxic.

The uncertainty is prompting kava-producing countries to act. With the help of the World Food Organization and the Food and Agricultural Organization of the United Nations, South Pacific countries are trying to come up with standards for kava. Next week, at a joint session in Vanuatu, they will discuss how the plant can be cultivated and processed safely. But until the standards are in place, drinking kava can be risky.

Though the cases of liver toxicity have been disputed through the years, several adverse event reports submitted to the US Food and Drug Administration (and obtained by The Verge through a FOIA request) show that every year, a few people get sick from consuming kava drinks or pills containing kava extract. Some people developed liver problems and severe skin rashes after drinking kava teas. In 2005, a 57-year-old woman died of acute hepatitis — an inflammation of the liver — after taking kava supplements.

"I have heard, at least anecdotally, that kava use today is more than it’s ever been in this country after a dip," says D. Craig Hopp, a program director at the National Center for Complementary and Integrative Health at the National Institutes of Health. "It’s concerning to the extent that we still don’t fully understand the issue of liver toxicity."

Harding Stowe, the co-owner of Brooklyn Kava, makes kava in his bar Amelia Holowaty Krales

Kava is a pepper plant, also called Piper methysticum, that’s originally from Polynesia, Micronesia, and Melanesia. In these cultures, people have been drinking kava ceremonially for more than 2,000 years — to celebrate important social events or welcome a new guest. More recently, kava has spread to many other South Pacific islands, including Hawaii, where it’s consumed recreationally. (In 1982, kava was intentionally introduced into Aboriginal communities in Australia as an alternative to alcohol.)

Many people turn to kava because they don’t like alcohol or are trying to quit drinking. "It’s non-alcoholic. It’s something natural," Ignacio, a 24-year-old resident of Brooklyn, told me as he was buying a pack of dried kava at Brooklyn Kava, which opened seven months ago in Bushwick. "It makes me relaxed, just more chill." Then there’s the sense of euphoria. "It kind of gives you this kind of immediate melting away of anxiety," says Harding Stowe, the co-founder of Brooklyn Kava. Judd Rench, who opened Bula Kava House in Portland, Oregon, in 2011, puts it this way: "It’s such a clear-head, nice, good, happy feeling."

In Europe and the US, kava became popular in the 1990s, with the spread of several medicinal products that contained kava extract to treat anxiety. And that’s when problems with kava began. At the end of the ’90s, several people in Germany and Switzerland had to undergo liver transplants after taking medications that contained kava. In the US, one case in 2000 involved a 14-year-old girl who was hospitalized with acute hepatitis after using two kava products for one to four months. She eventually got a liver transplant and survived.

Following these case reports, in 2002, several countries including Germany, Switzerland, France, Australia, and Canada restricted the sale of kava. (In 2014, Germany lifted its kava ban, but kava sales are still restricted.) In the US, the FDA didn’t ban kava, but issued an advisory to consumers that kava might lead to severe liver injury. Since then, scientists all over the world have analyzed the South Pacific plant to understand whether kava damages the liver and if so, why. Fifteen years later, no definite conclusions have been reached — and the only consensus is that more research needs to be done.

Some health effects are no secret. Kava can cause dry, itchy, and scaly skin if it’s consumed in large quantities. It’s also linked to nausea and weight loss. (Drinking too much kava is also associated with impotence and loss of sex drive.) When it comes to liver damage, however, the science gets murky. Several studies, for example, have shown that there’s an association between heavy consumption of kava and increased levels of a liver enzyme that suggests the flow of the liver’s bile might be affected. But when the plant’s active pharmacological components — called kavalactones — were tested on rats, there were no signs of liver toxicity, even when the animals were exposed to high dosages.

the only consensus is that more research needs to be done

The key to solving the mystery might lie in how kava is prepared. If the plant’s leaves and stems are used — not just the roots as it’s traditionally done — kava could be toxic, some scientists say. Or maybe kava becomes dangerous if the kavalactones are extracted using ethanol or acetone instead of water, the traditional preparation. Some people blame molds: kava is grown in tropical countries that are hot and humid, so if it’s not stored properly, dangerous molds can grow, (including aflatoxins that are known to damage the liver and cause cancer in people). A few think that genetic differences might make certain Caucasians more susceptible to kavalactones than Polynesians, increasing their risk of liver damage.

For others, it’s just a statistical problem. In the '90s, when kava spiked in popularity in Europe and the US, more people started consuming it. And when the number of people using a substance goes up, you’re bound to find someone who can’t tolerate it. "The sudden increase in kava consumption in the Western world allowed millions and millions of people to try kava, including those people who either had preexisting conditions, such as a compromised liver, or were just genetically allergic, genetically supersensitive to kava," says H.C. "Skip" Bittenbender, a kava expert at the University of Hawaii at Manoa. "So many millions of people were trying it that you’re going to find someone who has an adverse but idiosyncratic response."

A kava drink made by Harding Stowe at Brooklyn Kava, which opened seven months ago in Bushwick Amelia Holowaty Krales

For that "someone," however, the consequences can be scary. The Verge obtained 25 adverse events reports about kava that were submitted to the FDA from 2004 to 2015. (The agency said they couldn’t provide reports prior to 2004 because they were not recorded digitally.) The number isn’t high, but that’s not surprising. FDA research suggests that less than 1 percent of the severe adverse events caused by dietary supplements are actually reported to the FDA.

In one of these reports, a 40-year-old man received a liver transplant after using kava and being exposed to toxic chemicals like arsenic, copper, and chromium presumably in the kava (the report doesn’t specify). In another report, a 29-year-old woman developed "a horrible skin rash all over my entire body" after drinking one cup of kava tea. The rash got worse, with swelling and extreme itchiness, until the woman went to a dermatologist and was prescribed two anti-allergy and anti-inflammation medicines for two weeks. "I’ve never experienced anything like this," she wrote in the report.

In one report, a 39-year-old woman with no liver problems drank up to four cups of kava a day for six months before finding that her liver function was compromised. She stopped drinking kava and it took seven months for her liver enzyme levels to recover. In another report, a 57-year-old woman with no history of liver problems or alcohol abuse was diagnosed with acute hepatitis after consuming kava tablets to relieve stress. She received a liver transplant but never recovered from the procedure and died. "Her physicians believe Happy Camper Kava Kava damaged her liver," her husband wrote in the report. "No other causes found."

When I talked to owners of kava bars, most of them were quick to dismiss the safety concerns. Kava has been used in South Pacific islands for centuries and very few health problems have ever been noticed there, they say. If it’s made in the traditional way — extracting the kavalactones with water, using only the Noble variety, using only the plant’s roots — kava is safe, they say. After 14 years of investigation, the FDA hasn’t found a causal relationship between kava and liver dysfunction, says Tyler Blythe, the owner of two kava bars in California and the president of the American Kava Association, a membership-based organization that pushes for quality control among kava vendors in the US. "And of course they allow it to continue to be sold, so that’s very telling in and of itself how serious that link is," he adds.

Some of kava’s defenders say its safety record is far better than that of alcohol. Nearly 88,000 people die from alcohol-related causes every year in the US, according to the NIH. "[Kava has] gotten a pretty good track record," says Rench of Bula Kava House. "I always think it’s funny when people say, ‘Oh yeah, there were these cases of liver problems,’ and then they go drink alcohol, which is a proven poison that kills people daily. It’s kind of ironic."

Most kava bars will tell you not to drink alcohol while drinking kava just to be on the safe side — because both are processed through the liver. That’s what I was told at Kavasutra, and that’s what many other kava bar owners told me they recommend to their customers. "Better safe than sorry I think," says Rench. But he adds that the recommendation is also there because drinking alcohol and kava together just doesn’t feel nice. Others agree. "It gives you this weird, dizzy feeling," says Stowe of Brooklyn Kava. Matthew Clark, the co-founder of Ohana Kava Bar in Colorado Springs, says he sometimes turns customers away if they’re clearly intoxicated. Drinking kava might make them puke.

Drinking kava at Brooklyn Kava. "It's delicious," the girl said. Amelia Holowaty Krales

I’ll probably never like the taste of kava, but I was hooked on the relaxation effect. Going to Kavasutra was getting expensive, so I bought my own kava on Amazon, where a pound of kava goes for around $30 to $60. I tried to make it into a tasty drink one night, by mixing it with soy milk and cocoa powder in a blender — a recipe I found online. The result looked like a chocolate milkshake, but the taste was far from it. The kava’s earthy bitterness was still there, just made heavier and even harder to digest by the creamy milk. Before I knew it, my stomach was churning again. Three-quarters into the drink, I had a full-blown stomach ache.

As I lay on the couch, wondering why I was asking my body to ingest this foul drink for a little stress relief, I began worrying about the kava I had just consumed. What if my stomach couldn’t take it because the kava root was contaminated with molds? What if it had heavy metals, and I didn’t know? I’m really picky about my food, so why in the world was I trusting a random vendor on Amazon?

what if the kava root was contaminated with molds?

I was right to worry. In the US, kava is regulated by the FDA as a dietary supplement — which basically means it’s barely regulated. By law, dietary supplements don’t have to be proven safe by the FDA before going to market and manufacturers don’t have to get the agency’s approval before producing or selling the products. There are some regulations: the FDA put out so-called Good Manufacturing Practices (GMPs), which basically require manufacturers to meet certain quality standards, test their supplements, and maintain records.

Kava bars in the US don’t produce kava themselves; they just import it from abroad (no special permit is required to sell it). Though the GMPs apply to foreign manufacturers as well, the FDA is not going to do an inspection on a kava farm in Fiji, Vanuatu, or the Solomon Islands. And in these countries, quality controls can be lacking. In one study, researchers found that kava roots in Vanuatu were ground without being properly peeled and cleaned, according to a 2014 report on kava commissioned by the WHO and the FAO. Mold spots were sometimes removed "by rubbing the roots with a toothbrush, with limited success."

To address these concerns, the Coordinating Committee for North America and the South West Pacific at the WHO and the FAO is currently working on the development of standards for kava. This group, which represents the US and all the major countries where kava is produced, has a goal: to set rules on which parts of the plants and what varieties can be used safely, how they should be cleaned and processed, and what dosage of kava is safe for consumption.

A proposal for the standards will be discussed next week, but until they’re in place, it falls onto the kava vendors to make sure what they’re selling is safe. Kava bar owners in the US aren’t required by law to test the kava they sell, but most of them do it anyway to make sure it’s free of contaminants like mold, heavy metals, or dangerous bacteria like E. coli and Salmonella. They also want to make sure that the kava has enough kavalactones to have a psychoactive effect and that it is of the Noble variety — the plant variety that’s traditionally used in kava drinks and is considered safe. "We’re not required to have it tested, none of the kava bars are," says Stowe of Brooklyn Kava. "We just do it because we want to make sure that people are getting something that’s like quality and it’s not going to make them sick or is unhealthy or anything like that."

What about the kava found on Amazon though? I sent five samples of random kava I bought online to Blythe at the American Kava Association, which runs a lab and tests samples for a fee for its members. Blythe tested the kava I sent him for quality and potency, as well the root’s microbial and heavy metals information. One sample tested positive for coliforms, a type of bacteria that can come from human or animal feces. Though some coliforms are harmless, others can make you sick. Another sample contained Tudei kava, a kava variety that has longer lasting psychoactive effects and is known to cause nausea. (Its export is banned in Vanuatu and Fiji.) "While it is thought to be undesirable as a daily drinking kava, it is not necessarily dangerous to drink every once in a while," Blythe wrote in an email. The instructions on the packaging however — which didn’t specify this was Tudei kava — recommend taking one tablespoon three times a day.

Despite that, Blythe said that the results were "better than I thought we would find, honestly." And that’s good news. Blythe is adamant about kava vendors testing their products. "We’re very very strict on quality controls. If you’re going to sell kava to consumers, we want to see certificates of analysis performed," Blythe says. "All of this is important so that we don’t have another scare."

After Kavasutra, I visited Brooklyn Kava, which has more of a hipster cafe vibe. Stowe, one of the owners, fixed me a kava drink that also contained lavender syrup, thyme, and chai concentrate. It was a whole different story. Finally the bitter, pungent taste of kava was masked, and I could swallow the drink without gagging. Now, if I prepare a kava drink at home, I use the recipe Stowe gave me.

Though I enjoy the relaxing feeling kava gives me at the end of the day, those cases of skin rashes, hepatitis, and liver failure never leave the back of my head as I’m sipping. What if the kava I’m served at a bar contains heavy metals or liver-damaging molds? There’s no real way to know. Right now, I have to blindly trust kava bar owners to source their kava from a reliable farmer in the South Pacific and run the adequate safety tests.

After going to Kavasutra, I found out that the owner of that kava bar, Dylan Harrison, spent a year in prison in 2013 for manufacturing synthetic marijuana and selling it at convenience stores as an "herbal incense." (Harrison never answered requests for comments for this article.) Can I really trust him for giving me the best, safest kava on the market? I’m not sure. But can I trust the sandwich I buy for lunch at the corner deli is not infected with E. coli or Salmonella? Again, there’s no way to know.

"Nothing is safe," Christian Skonberg, a senior research scientist at the pharmaceutical company Novo Nordisk A/S, who reviewed several studies about kava, told me. "What I think everyone should remember is this Aristotle principle that everything is a poison. It’s just the dose that determines the poison — and that goes for natural products as well."

Loading comments...