Liquorice-induced rise in blood pressure: a linear dose-response relationship

• Published in: Journal of Human Hypertension
• Main Authors: Sigurjonsdottir H A, Franzson, L, Manhem, K, Ragnarsson, J, Sigurdsson, G, Wallerstedt, S
• Other Authors: Department of Medicine, Sahlgrenska University Hospital/Ostra, Gröna Stråket 8, 413 45 Göteborg, Sweden.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2011
• Subjects: Adult; Analysis of Variance; Blood Pressure; Confidence Intervals; Dose-Response Relationship; Drug; Female; Follow-Up Studies; Glycyrrhiza; Heart Rate; Humans; Hypertension; Iceland; Male; Plants; Medicinal; Potassium; Reference Values; Regression Analysis; Sweden; Time Factors
• Online Access: http://hdl.handle.net/2336/119686; https://doi.org/10.1038/sj.jhh.1001215

To access publisher full text version of this article. Please click on the hyperlink in Additional Links field To clarify the dose-response and the time-response relationship between liquorice consumption and rise in blood pressure and explore the inter-individual variance this intervention study was designed and executed in research laboratories at University hospitals in Iceland and Sweden. Healthy, Caucasian volunteers who also served as a control for himself/herself consumed liquorice in various doses, 50-200 g/day, for 2-4 weeks, corresponding to a daily intake of 75-540 mg glycyrrhetinic acid, the active substance in liquorice. Blood pressure was measured before, during and after liquorice consumption. Systolic blood pressure increased by 3.1-14.4 mm Hg (P < 0.05 for all), demonstrating a dose-response but not a time-response relationship. The individual response to liquorice followed the normal distribution. Since liquorice raised the blood pressure with a linear dose-response relationship, even doses as low as 50 g of liquorice (75 mg glycyrrhetinic acid) consumed daily for 2 weeks can cause a significant rise in blood pressure. The finding of a maximal effect of liquorice after only 2 weeks has important implications for all doctors dealing with hypertension. There does not seem to be a special group of responders since the degree of individual response to liquorice consumption followed the normal distribution curve.