Kudzu is one of the few plants besides soybeans to contain large amounts of isoflavones. Readings of historical Chinese texts (Li, 1590–1596; Sun, circa 600 AD) reveal that extracts of the kudzu root have been used to treat alcoholism and drunkenness since at least 600 AD. Recent analysis of the kudzu root has revealed it contains 3 active isoflavones that have antidipsotropic (anti-drinking) activity: daidzin, daidzein,and puerarin. Of the total isoflavone content in soybeans, approximately 40% is comprised of daidzein/daidzein.
In the current study, 20 men participated in a placebo-controlled, double-blind, between subjects design experiment (n=10/group) that tested the effects of kudzu extract for its ability to alter alcohol consumption in a natural settings laboratory. A single dose of kudzu extract (2 g total with an active isoflavone content of 520 mg) or placebo was administered 2.5 hours before the onset of a 90 minute afternoon drinking session during which participants had the opportunity to drink up to 6 beers ad libitum. During the baseline session, the placebo-randomized group consumed 2.7+/-0.78 beers before treatment and increased consumption to 3.4+/-1.1 beers after treatment. The kudzu group significantly reduced consumption from 3.0+/-1.7 at baseline to 1.9+/-1.3 beers after treatment. The placebo-treated group opened 33 beers during baseline conditions and 38 following treatment whereas the kudzu-treated group opened 32 beers during baseline conditions and only 21 following treatment. Additionally, kudzu-treated participants drank slower.
The results of this study show for the first time that a kudzu extract limits male alcohol consumption during an afternoon of drinking. It is not possible to determine from the experimental design the kudzu components responsible for the effect but previous work in animals and humans points to isoflavones. There is sufficient data to investigate the effects of soy extracts on binge drinking.
Penetar DM, Toto LH, Lee DY, et al. A single dose of kudzu extract reduces alcohol consumption in a binge drinking paradigm. Drug Alcohol Depend. (2015).