Liquorice consumption and salivary testosterone concentrations

Liquorice consumption has been shown to substantially reduce serum testosterone concentration. An explanation for this result was that the active component in liquorice (glycyrrhizic acid) interfered with 17β-hydroxysteroid deyhydrogenase, which has been shown in vitro to catalyse the conversion of androstenedione to testosterone. We twice attempted to replicate this effect of liquorice but could not. We identified differences between our methods and those of the previous study and possible statistical anomalies (including inappropriate use of statistical tests) in the earlier report.