As many people have heard, a team of medical researchers affiliated with Harvard Medical School Recently reported that the common Chinese herb kudzu (Pueraria lobata), which also grows as a wayside vine in the U.S. Southeast, helps to suppress the desire for alcohol (Lukas et al. 2005). This finding was first described in 1970s research with animals specially bred to be alcohol-dependent; work corroborating these earlier findings was concucted from 1996 to 2003 (Overstreet et al. 1996; Overstreet et al.2003).
Kudzu, however, has played a prominent role for centuries in herbal formulas designed to deal with human drunkenness. The Chinese appeared not to postulate why kudzu might work; they simply observed its effects over generations. Anecdotal data suggest that kudzu works to reduce alcohol cravings in up to 80% of alcohol abusers. This stimulated early pharmacological researchers to investigate kudzu's mechanisms of action.
Kudzu is native to China, where it was widely used as a starch-rich food, a food thickener, and a medicine. It has also been naturalized in the Southeast, where it climbs prolifically over trees, creating a panoramic backdrop at dusk that is reminiscent of Jurassic Park, with shapes similar to every dinosaur imaginable. Eventually kudzu's sheer lushness kills its host trees. It is said to grow so fast that if one is stopped at a traffic light too long it will grab the tires!
Kudzu is considered by most to be a scourge of a weed. However, according to one of the most respected works of herbal medicine in Chinese literature, Ben Cao Gang Mu (1596) or the Great Compendium of Materia Medica of Li Shi Zhen, kudzu root was reported to detoxify alcohol. Subsequently kudzu became a feature in many formulas throughout the centuries for the relief of drunkenness.
Scientific research suggest it is kudzu's isoflavone compounds, daidzein and daidzin, which are partially responsible for this effect - although the same research showed that the natural plant, not surprisingly, was more effective than the isolated compounds. These compounds are not unique to kudzu but the alcohol cessation effect seems to be. When hamsters were bred to drink the equivalent of a case of wine daily, they could literally drink themselves to death. When kudzu extract was administered, their desire for alcohol was cut in half (Keung and Vallee 1994).
In the human study of Lukas et al. (2005), men and women defined as "heavy drinkers" were administered two 500 mg capsules of kudzu or placebo three times daily for seven days and then given the chance to drink whatever they liked. The capsules were characterized as containing 19% pueararin, 4% daidzin, and 2% daidzein. Administration of kudzu resulted in significant reductions in the number of alcohol drinks consumed, an increase in the average number of sips per beer, a reduction in the size of the sips drunk, and a reduction in the overall volume of alcohol consumed. It also took subjects treated with kudzu longer to open and drink their beers than when the same subjects were given the placebo. The authors concluded that a one-week treatment of kudzu extract resulted in a significant reduction in the number of beers consumed in a simulated natural environment.
This scientific research coincides with a small, informal, unpublished pilot study conducted in England. Eleven individuals were given an herbal combination containing kudzu. Of those who started the experiment, three dropped out because they were not enjoying their alcohol and one was getting drunker on fewer drinks. Of those who completed the experiment, 64% claimed to be drinking less and experienced less alcohol cravings; 60% said they experienced other improvements such as greater alertness, improved emotional well-being, and reduced stress; 55% said they felt improvements in physical symptoms such as increased energy levels, less headaches and less hangovers. The average number of alcohol units drunk prior to the kudzu compound was 36 units; this was reduced to 16 units after consumption of the herbal compound. Some herbal consumers reduced their intake by 75%.
Some mechanisms of action associated with this activity have been postulated, including enhancement of hepatic antioxidant defense systems by increasing activities of alcohol dehydrogenase and aldehyde dehydrogenase, and increased superoxide dismutase and catalase activities, all of which can help clear alcohol from the system, as well as protect the liver from damage.
As is typical of such research, the goal is to turn this traditionally used botanical into a multi-million dollar pharmaceutical - likely at a high cost associated with all the advertising needed to make it a household name. Nevertheless, this humble botanical now sits on the shelves of health food stores awaiting thoses who want to get their alcohol consumption under control, and those parents who would like to spike the water of their teenagers.
The very good news: thus far, based on centuries of use in Asia (representing most of the world's population) and on the recent scientific research, kudzu appears to be completely safe. It is actually used as a food thickener in Japanese macrobiotic cooking. Kudzu does, however, have positive side effects: in scientific studies it has been shown to have a protective effect on the liver, a bonus for those who drink alcohol. It is one of the most fantastically effective botanicals for relieving neck and shoulder tension. And it is used in China to improve hearing - not bad for a humble and inexpensive wayside botanical.
References
Keung WM, Vallee Bl. 1994. Therapeutic lessons from traditional Oriental medicine to contemporary Occidental pharmacology. EXS 71: 371-381.
Lukas S, et al. 2005. Alcoholism: Clinical and Experimental Research. 29(5): 756-762.
Overstreet D, et al. 2003. Suppression of alcohol intake after administration of the Chinese herbal medicine, NPI-028, and its derivatives.
Alcohol Clin Exp Res 20: 221-227.
Overstreet D, et al. 2003. NPI-031G (puerarin) reduces anxiogenic effects pf alcohol withdrawal or benzodiazepine inverse or 5HT2C agonist. Pharmacol Biochem Behav. 2003 Jun; 75(3):619-25.