In a recent study published in The American Journal of Clinical Nutrition, researchers analyzed the results of every day intake of licorice on blood pressure (BP).
Licorice has been used as a flavor and herbal medicine for hundreds of years. Nevertheless, evidence suggests its intake could elevate BP through glycyrrhizic acid (GA). Ammonium chloride is a substitute for sweet licorice because it doesn’t elevate BP and is marketed as salty licorice. The World Health Organization (WHO) and the European Union (EU) have suggested that ≤ 100 mg of GA per day is protected.
The GA content in sweet licorice varies by plant age, country of origin, species, and storage conditions. Up to now, 13 studies have been published on the results of sweet licorice on BP, but none were randomized controlled trials. Subsequently, it’s unclear whether every day sweet licorice consumption is protected.
Study: A low dose of every day licorice intake affects renin, aldosterone, and residential blood pressure in a randomized crossover trial. Image Credit: Latest Africa / Shutterstock
In regards to the study
In the current study, researchers examined the results of every day consumption of sweet licorice on BP. Healthy volunteers aged 18–30 were recruited in Sweden between January and April 2023. Individuals with hypertension, eating disorders, drug or alcohol abuse, heart problems, headache, liver disease, peanut allergy, intolerance to licorice, and kidney disease were excluded.
The team implemented a two-treatment, two-sequence, two-period, non-blinded, crossover study design. Two groups were constituted – intervention then control (I-C) and control then intervention (C-I). Sweet licorice pastilles produced from Glycyrrhiza glabra were used because the intervention. They contained 2% GA, 4% sugars, and 0.03% salt, as specified by the manufacturer.
Vegan salty licorice confectionaries, which contained 0.05% salt, 5.5% ammonium chloride, and no GA or sugars, were used because the control. Participants consumed 14.5 pastilles a day in the course of the intervention and a couple of.9 g of salty licorice per day in the course of the control period. Participants’ weight, height, and office BP were measured at baseline.
A questionnaire was administered to acquire information on age, sex, physical activity, alcohol or tobacco use, medications, heredity for heart problems and diabetes, and dietary supplements. Weight was also measured at the top of every period. BP was measured after a five-minute rest. Participants abstained from strenuous activity, caffeine, alcohol, and nicotine products at the least one hour before measurements.
Baseline office BP was measured using a validated sphygmomanometer, and a semi-automatic device measured home BP thrice within the morning and evening. Blood samples were collected at baseline and the top of the intervention, control, and first washout periods. Plasma sodium, creatinine, potassium, lipid profile, aldosterone, renin, and N-terminal prohormone of brain natriuretic peptide (NT-ProBNP) were estimated.
The study included 28 participants, with 14 females and 14 males equally represented in each groups. The common systolic and diastolic office BP levels were 109.1 mmHg and 65 mmHg, respectively. Compared to manage, a rise in systolic home BP was observed in the course of the intervention period. The systolic BP increased from day 5 until day 14 in comparison with three days before the intervention.
Nonetheless, from day 11 of the post-intervention washout period, the systolic BP didn’t differ from that three days before the intervention. An increased diastolic home BP was observed from day 7 in comparison with three days before the intervention. The change in diastolic BP was not different between the intervention and control periods.
The diastolic BP was higher on day 14 of the post-intervention washout period than on the three days preceding the intervention. Aldosterone and renin levels declined at the top of the intervention compared to manage. Body weight and NT-ProBNP levels increased, while creatinine declined in the course of the intervention relative to the control period.
Values below the lower quantification level were observed for aldosterone and renin for a couple of participants. There have been some protocol deviations; three participants didn’t take the sweet licorice pastilles on some days. Throughout the intervention, one individual developed several itchy, red rashes across the thorax and upper legs that were proof against treatment but subsided within the washout period.
Taken together, every day licorice consumption such as 100 mg of GA increased home BP and suppressed aldosterone and renin levels. Licorice intake increased systolic BP from day 5 until day 14, suggesting that continued or prolonged intake might amplify this effect. Notably, the study was non-blinded, as taste differences between sweet licorice and confectionaries with ammonium chloride are noticeable.
To conclude, the findings reveal that licorice is stronger than previously known. Each day intake (100 mg GA) increased BP in young people. Further, probably the most sensitive quartile of people had elevated weight and markers of cardiac strain (NT-ProBNP). Overall, awareness of those effects is obligatory given the on a regular basis use of licorice, and more stringent warning labels are required for confectionaries containing GA.