Effect of licorice on the reduction of body fat mass in healthy subjects

Abstract

The history of licorice, as a medicinal plant, is very old and has been used in many societies throughout the millennia. The active principle, glycyrrhetinic acid, is responsible for sodium retention and hypertension, which is the most common side-effect. We show an effect of licorice in reducing body fat mass. We studied 15 normal-weight subjects (7 males, age 22-26 yr, and 8 females, age 21-26 yr), who consumed for 2 months 3.5 g a day of a commercial preparation of licorice. Body fat mass (BFM, expressed as percentage of total body weight, by skinfold thickness and by bioelectrical impedance analysis, BIA) and extracellular water (ECW, percentage of total body water, by BIA) were measured. Body mass index (BMI) did not change. ECW increased (males: 41.8+/-2.0 before vs 47.0+/-2.3 after, p<0.001; females: 48.2+/-1.4 before vs 49.4+/-2.1 after, p<0.05). BFM was reduced by licorice: (male: before 12.0+/-2.1 vs after 10.8+/-2.9%, p<0.02; female: before 24.9+/-5.1 vs after 22.1+/-5.4, p<0.02); plasma renin activity (PRA) and aldosterone were suppressed. Licorice was able to reduce body fat mass and to suppress aldosterone, without any change in BMI. Since the subjects were consuming the same amount of calories during the study, we suggest that licorice can reduce fat by inhibiting 11beta-hydroxysteroid dehydrogenase Type 1 at the level of fat cells.

Effect of dietary supplementation of licorice extract and a prebiotic on performance and blood metabolites of broilers

“…Aoki et al (2007) showed that LFO reduced body weight gain and abdominal white adipose tissues in mice fed high-fat diets. Furthermore, in other studies licorice hydrophobic flavonoids decreased abdominal fat in humans and mice (Armanini et al, 2003;Nakagawa et al, 2004). Plant herbs or their extracted oils containing terpenoids, may improve poultry health and production.…”

“…At day 49 birds fed the diets supplemented with licorice showed lighter (P <0.05) abdominal fat pads as compared to those fed the control diet (Table 5). Previous studies also showed that licorice flavonoids reduced the abdominal fat in other species (Armanini et al, 2003;Nakagawa et al, 2004;Tominaga et al, 2006;Aoki et al, 2007). Tominaga et al (2006) indicated that the effect of licorice on reduction of abdominal fat could be due to factors such as suppression in energy intake, reduction of lipid absorption, enhancement of fatty acid oxidation or reduction in biosynthesis of fatty acids.…”

“…The additions of licorice extract or the prebiotic did not have a significant effect on BW and FCR during the starter, grower and finisher periods. However, previous studies with other species of animals have shown that licorice flavonoids suppress BW by reducing body fat mass (Armanini et al, 2003;Nakagawa et al, 2004;Tominaga et al, 2006;Aoki et al, 2007). They suggested enhancement of fatty acid oxidation and reduction in biosynthesis of fatty acids are possible mechanisms for the reduction of abdominal fat and lower body weight gains (BWG).…”

Liquorice‐induced hypokalaemia and water retention in the absence of hypertension

“…The fall in both R/H and Xc/H values and the reduction in R/Xc ratio, suggested a fluid excess in the subcutaneous tissues (Piccoli et al, 1994(Piccoli et al, , 1995. In a previous study the bioelectrical impedance analysis demonstrated that liquorice at a dose of 3.5 g daily for 2 months significantly increased the body water (Armanini et al, 2003).…”

Arrhythmogenicity of weight-loss supplements marketed on the Internet

“…There is conflicting information about the effectiveness of licorice for weight loss. 7,27 Licorice has antispasmodic, anti-inflammatory, laxative, and soothing properties. 7 The mineralocorticoid effects of licorice can induce fluid retention and worsen congestive heart failure.…”