Glabridin content and metabolic effects of liquorice confectionaries: A secondary analysis of a randomized crossover trial in young adults

Abstract

Background Liquorice, a popular confectionary product, contains several bioactive compounds. Amongst them, glycyrrhizic acid is associated with increased blood pressure, and glabridin is associated with anti-inflammatory and glucose-lowering effects. The aim was to assess the association between short term liquorice intake at a dose known to elevate blood pressure, and markers of dysglycemia, blood lipids, high-sensitivity C-reactive protein (hsCRP), and calcium metabolism. Methods In a 2x2 crossover study, 28 healthy adults were randomized to consume liquorice or a control product in alternating 2-week periods, with measurements of blood glycated haemoglobin A1c as well as plasma glucose, calcium ion, parathyroid hormone, and lipids at the end of each period. Liquorice glabridin content was determined via LC-MSMS analysis. Results The liquorice contained 0.25 ± 0.14 µg glabridin per mg. The plasma hsCRP value increased by 32.5% (95% CI −9.7 to 74.6) during the intervention period vs 311.5% (95% CI −40.8 to 663.7) during the control period, P = .045. No effects on the other markers were observed. Conclusion Liquorice intake did not improve metabolic markers but attenuated hsCRP elevation. The potential metabolic benefits of glabridin are unlikely to outweigh the hypertensive effects when consumed as whole liquorice.