What the Polynesians believed--and what many Americans now believe too--is that the lowly kava root has mind-altering effects. Prepared and consumed properly, it is said to alleviate stress, ease melancholy and generally elevate mood--all without addiction or hangover. Sound too good to be true? That hasn't stopped supermarkets, drugstores, health-food stores and discount chains like K Mart from stocking up on kava capsules, droplets and tea bags--or consumers from eagerly snapping them up. Kava sales in these stores jumped from barely a trickle to $3 million last year, and should double in 1998.
Critics are uneasy. Kava, they fear, will turn out to be merely herbal medicine's root du jour, a scientifically unproven preparation that is at best useless and at worst dangerous. But doctors and consumers are two different groups, and even as concerns are raised, kava's popularity continues to grow. "I think kava is really hot," says Dr. Hyla Cass, a UCLA psychiatrist and co-author of Kava: Nature's Answer to Stress, Anxiety, and Insomnia (Prima Health). "It's a sleeper."
For all its alleged powers, kava is a pretty pedestrian plant. One of 2,000 members of the extended pepper family, it grows principally in the South Pacific, where it is harvested like any other cash crop. The root was largely unknown in the U.S., but that changed in 1996. That year, a coalition of 21 herbal-product makers devised a plan to bring more kava to American shores and shelves. Using aggressive ad campaigns, they quickly raised the profile of the root. When word began circulating that kava might have the power to calm--and when ABC ran a story to that effect--the herb found a ready market. Says Mark Blumenthal, executive director of the American Botanical Council: "There are an increasing number of people interested in the idea that natural is better."
And by many accounts, kava is indeed better. Even critics admit that it has mild pharmacological properties and produces none of the side effects of Valium and other sedatives. "It's not a major difference, but I do feel a lot calmer," says Amie McGoon, 32, a California graduate student who began taking kava after antidepressants failed.
The Food and Drug Administration is less calm. Neither it nor anyone else knows precisely how kava works. The prevailing thinking is that its active ingredient is a class of molecules known as kavalactones, plant metabolites that affect the limbic system, the emotional center of the brain. According to Cass, kava works on the same amino-acid sites as Valium; while Valium binds to so-called GABA receptors, kava causes more of them to form.
That's what studies with rats suggest, anyway. But rats aren't people, and although researchers in Germany have reported that kava is safe and effective for humans--prompting that country to approve the root as a treatment for mild anxiety--many U.S. physicians are unimpressed. "If a substance has an effect on mood, that doesn't necessarily mean it has therapeutic value," says psychiatrist Benedetto Vitiello of the National Institute of Mental Health. "A good cup of coffee has an influence on mood, but it's not really an antidepressant."
Then there's the danger that kava could actually do harm. Doctors know that heavy use over even a few months can cause temporary yellowing and flaking of the skin. The effects of longer use are unknown. Psychological addiction is a risk even if physical addiction isn't. Also worrisome is the danger of adverse drug interaction. A kava user in Georgia who had been taking the sedative Xanax had blackouts when he switched from the drug to the root.
For now, the FDA will allow kava manufacturers to promote their product only in a general way, advertising it as a supplement without citing any specific medical benefits. Until formal studies are conducted, those restrictions will stand. Even without a government green light, however, kava will probably remain popular, sold as an antianxiety herb that dare not call itself that. "People like the idea of feeling mellow but staying alert," says Blumenthal. "That's what kava does." The question is, At what cost?