Chengguo Xing, a member of the research team at the University of Minnesota, is more cautious, but he too is optimistic about ‘awa’s impact on human health. “What we can say at this moment is that kava can slow down cancer development in animal models,” he says. “We don’t know if kava can be used to treat cancer [in humans].” The Minnesota studies were originally designed “to explore if ex-smokers … should take kava as a preventative approach to reduce their risk of lung cancer,” Xing says. To test the question, mice in the very early stages of cancer were given ‘awa in their food.
“Our data clearly demonstrated that the mice that take kava on a daily basis have a smaller lung cancer load [number of tumors], and the tumors are smaller, too,” says Xing, who notes similar results with colon cancer.
Both Zi and Xing say their interest in ‘awa as a cancer-fighting agent sprang from a study that found significantly lower cancer rates in South Pacific societies where ‘awa was still commonly used— especially among men, the primary users of ‘awa, even though the men often smoked.
The University of Minnesota team also looked into the link between ‘awa and liver damage and found something salient: “We noticed that the commercial preparation of ‘awa has quite a different composition compared to the traditionally prepared water mix or coconut water mix,” says Xing. 88The group obtained both traditional ‘awa infusions and several brands of commercially prepared ‘awa, broke them into “fractions,” analyzed the components of each fraction and fed the different fractions to different groups of mice. “The mice that got the traditional kava survived okay,” says Xing. “But the mice that got the extra components from commercial kava not detectable in traditional kava were immobilized really quickly and died.” In fact, he adds, they died too quickly to determine whether liver damage had occurred: “The extra components in commercial kava are definitely more toxic. Whether they are more liver-toxic, we don’t know at this point.”