Licorice root

What human studies say about licorice root

• Dental caries bacteria · Systematic review · 2020
  The review qualitatively synthesised six studies and concluded that licorice extracts were associated with lower Streptococcus mutans counts in children. It did not report a pooled estimate. Limitation: Only PubMed and Google Scholar were searched, there was no meta-analysis, and the included studies were small; the abstract reports no caries outcomes or risk-of-bias assessment. PubMed 33402612
• Obesity and metabolic markers · Randomized controlled trial, 66 participants · 2024
  Compared with placebo plus the same low-calorie diet, licorice extract was associated with greater improvements in body weight, BMI, body fat, lipid profile, fasting glucose, insulin and HOMA-IR at 8 weeks. Limitation: Small sample, short 8-week duration, and an extract dose that is not comparable to licorice eaten as food; the authors call for confirmatory research. PubMed 39080737
• H. pylori eradication · Randomized controlled trial, 120 participants · 2016
  H. pylori eradication was 83.3% with licorice added to the standard triple regimen versus 62.5% with the regimen alone, a statistically significant difference assessed six weeks after therapy. Limitation: The abstract does not describe blinding or the licorice dose and preparation, and it reports only a simple comparison without adjustment. PubMed 27614124
• Blood pressure (safety) · Non-randomized clinical trial · 2017
  Compared with a control group, two weeks of liquorice intake raised systolic and diastolic blood pressure, systemic vascular resistance, extracellular fluid volume and arterial stiffness measures. Limitation: Only 22 volunteers ate liquorice, they were not randomised against controls, and exposure lasted two weeks, so longer-term effects are unknown. PubMed 28887501

Most studies used extracts or doses that differ from home cooking. Full details in the Nourilo Research Library.

Safety: Contains glycyrrhizin. Large amounts or long-term use have been linked to raised blood pressure and irregular heartbeat, and even smaller amounts have caused problems in people with high blood pressure, heart or kidney conditions, or a high-salt diet. Large amounts are unsafe in pregnancy, and it can interact with corticosteroids. Source: NIH NCCIH — Licorice Root