Antiatherosclerotic effects of licorice extract supplementation on hypercholesterolemic patients: decreased CIMT, reduced plasma lipid levels, and decreased blood pressure.
BACKGROUND
Ethanolic extract of licorice root has been shown to reduce low-density lipoprotein (LDL) oxidation in atherosclerotic mice and in both hypercholesterolemic and normal lipidemic humans.


OBJECTIVE
This study examined the effect of licorice-root extract on carotid intima-media thickness (CIMT) in individuals with hypercholesterolemia.


METHODS
Individuals with hypercholesterolemia (total cholesterol ≥6.18 mmol/L [240 mg/dL]) and without significant stenosis were randomly allocated to two groups: an experimental group that consumed 0.2 g/day of ethanolic extract of licorice root for 12 months, and a control group that received a placebo.


RESULTS
Of 110 eligible participants, 94 (41-80 years old) completed the study. A significant CIMT decrease from 0.92±0.25 mm to 0.84±0.21 mm was observed in the experimental group compared with an increase from 0.85±0.17 mm to 0.88±0.19 mm in the control group. Mean plasma total cholesterol levels and LDL cholesterol decreased, at the range baseline to 1 year, from 284±32 mg/dl to 262±25 mg/dl and from 183±8.5 mg/dl to 174±9.1 mg/dl, respectively, for the experimental group (p<0.001) and from 291±35 to 289±31 mg/dl and from 177.6±10.7 to 179.3±9.6 (p=0.08), respectively, for the control group. Mean high-density lipoprotein (HDL) did not change significantly in either group. In the experimental group, systolic blood pressure decreased from 138±12 mmHg to 125±13 mmHg after 1 year (p=0.01) and increased from 136±15 mmHg to 137±13 mmHg in the control group. Diastolic blood pressure decreased from 92±9 mmHg to 84±10 mmHg (p=0.01) in the experimental group and increased from 89±11 mmHg to 90±8 mmHg in the control group.


CONCLUSIONS
Following 1 year of licorice consumption, mean CIMT, total cholesterol, LDL levels, and blood pressure were decreased. This suggests that licorice may attenuate the development of atherosclerosis and of related cardiovascular diseases.
Department of Family Practice, Leumit Health Services, Haifa, Israel.|The Ruth & Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel; yfogelman@gmail.com.
Yacov
Y
Fogelman
The Ruth & Bruce Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, Israel.|Department of Medical Imaging, Unit of Ultrasound, Rambam Health Care Center, Haifa, Israel.
Diana
D
Gaitini
Department of Physical Therapy, Faculty of Social Welfare and Health Sciences, Haifa University, Haifa, Israel.
Eli
E
Carmeli
atherosclerosis; blood pressure; cardiovascular risk reduction; carotid intima media thickness; licorice extract