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Liquorice consumption and salivary testosterone concentrations
Lancet (London, England)
|November 22, 2001
Summary
Liquorice consumption may not lower testosterone levels as previously suggested. Our replication attempts failed to confirm that glycyrrhizic acid significantly impacts testosterone production in men.
Area of Science:
- Endocrinology
- Human Physiology
- Pharmacology
Background:
- Previous studies suggested liquorice consumption reduces serum testosterone.
- This effect was attributed to glycyrrhizic acid interfering with 17 beta-hydroxysteroid dehydrogenase.
- The enzyme 17 beta-hydroxysteroid dehydrogenase catalyzes androstenedione to testosterone conversion in vitro.
Purpose of the Study:
- To replicate the reported effect of liquorice on serum testosterone concentration.
- To investigate the potential mechanism involving glycyrrhizic acid and 17 beta-hydroxysteroid dehydrogenase.
- To critically evaluate the methodology and statistical analysis of prior research.
Main Methods:
- Two independent attempts were made to replicate the findings of the original study.
- Standardized protocols were employed to assess serum testosterone levels following liquorice consumption.
- Methodological differences and statistical approaches were compared with the previous report.
Main Results:
- Replication attempts failed to demonstrate a significant reduction in serum testosterone concentration.
- No evidence was found to support the hypothesis that glycyrrhizic acid inhibits 17 beta-hydroxysteroid dehydrogenase activity in vivo.
- Discrepancies in methodology and potential statistical anomalies were identified in the earlier study.
Conclusions:
- The purported testosterone-lowering effect of liquorice consumption could not be confirmed.
- The proposed mechanism involving glycyrrhizic acid and 17 beta-hydroxysteroid dehydrogenase is not supported by this study.
- Caution is advised regarding the interpretation of previous findings due to methodological and statistical concerns.
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